Common use of Introductory Clause in Contracts

Introductory. Horizon Pharma, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon Pharma, AmeriVest Properties Inc., a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares (the “Firm Common Shares”) of its common stock, par value $0.0001 .001 per share (the “SharesCommon Stock”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares shares (the “Optional Common Shares”) of Common Stock, as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Common Shares and, if and to the extent such option is exercised, the Optional Common Shares are collectively called the “Offered Common Shares.” ▇F▇▇▇▇▇, B▇▇▇▇ W▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenFBW”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Common Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 SB-2 (File No. 333-16850486676), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Common Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Such prospectus, 2011 describing in the Offered Shares and form first used by the offering thereof Underwriters to confirm sales of the Common Shares, is called the “Preliminary Prospectus,.” and All references in this Agreement to the Preliminary Prospectus and any other Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus that describes or the Offered Shares and the offering thereof and is used prior Prospectus, or any amendments or supplements to the filing any of the Prospectus foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“E▇▇▇▇”). The Company hereby confirms its agreements with the Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon Pharma, Inc.Addus HomeCare Corporation, a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 1,075,267 shares (the “Primary Firm Shares”) of its common stock, par value $0.0001 0.001 per share (the “Shares”); and the stockholder of the Company named in Schedule B (the “Selling Stockholder”) propose to sell to the Underwriters an aggregate of 1,024,733 Shares (the “Secondary Offered Shares”). The [ ] Primary Firm Shares to be sold by the Company and the Secondary Offered Shares to be sold by the Selling Stockholder are collectively called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 315,000 Shares (the “Optional Shares”), as provided in Section 2. The additional [ ] Primary Firm Shares and, if and to be sold by the Company pursuant to extent such option is exercised, the Optional Shares are collectively called the “Optional Primary Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇▇▇▇ LLC (“Jefferies”), ▇RBC Capital Markets, LLC (“RBC”) and ▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company& Associates, LLC Inc. (“Cowen▇▇▇▇▇▇▇ ▇▇▇▇▇”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)214988, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formis

Introductory. Horizon Pharma, Inc.First Potomac Realty Trust, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares 2,500,000 of its common stockshares (the “Firm Shares”) of beneficial interest, par value $0.0001 .001 per share (the “Common Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 375,000 Common Shares (the “Option Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated KeyBanc Capital Markets Inc. (“StifelKCM”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company is the sole general partner of First Potomac Realty Investment Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed on April 16, 2007 a registration statement on Form S-3, which was subsequently amended on August 19, 2008 and August 22, 2008 (File No. 333-142147), which contains a form of prospectus to be a part thereof at used in connection with the time public offering and sale of effectiveness pursuant the Shares (the “Base Prospectus”). Such registration statement, herein referred to Rule 430A under the Securities Act, is called as the “Registration Statement.,” Any registration statement shall be deemed to include all information omitted therefrom in reliance upon Rules 430A or 430B under the Securities Act and all information incorporated by reference therein. The form of final prospectus relating to the Shares first filed by the Company with the Commission pursuant to Rule 462(b424(b) under the Securities Act is called herein referred to as the “Rule 462(bProspectus.” The Base Prospectus, as supplemented by any preliminary prospectus (including any preliminary prospectus supplement) relating to the Shares used prior to the date hereof is herein referred to as a “Preliminary Prospectus.” Any reference herein to the Registration Statement,” , any Preliminary Prospectus or the Prospectus or to any amendment or supplement to any of the foregoing documents shall be deemed to refer to and from include any documents incorporated by reference therein and any supplements or amendments thereto, filed with the Commission after the date and time of filing of the Prospectus under Rule 462(b424(b) Registration Statement under the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Securities Act, 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing termination of the Prospectus (offering of the Shares by the Underwriters. Each of the Company and the Operating Partnership hereby confirms its agreements with the Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon PharmaNPS Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters Underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 6,880,000 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 6,880,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,032,000 Shares as provided in Section 2. The additional [ ] 1,032,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ Jefferies & Company, Incorporated Inc. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) Canaccord Genuity Inc. have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 S-3 (File No. 333-168504), which contains 159321) including a form of base prospectus to (the “Base Prospectus”) that will be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness (“Effective Time”) pursuant to Rule 430A 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of the filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]September 15, 2011 2010 describing the Offered Shares and the offering thereof thereof, together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus supplement to the Base Prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formthe

Introductory. Horizon Pharma, Inc.Immune Design Corp., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [—] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ [—] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [—] Shares as provided in Section 2. The additional [ [—] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ LLC and Company, Leerink Partners LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 00578 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Prospectus.” The preliminary prospectus dated [ [—], 2011 2014 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus in preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaMirati Therapeutics, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 2,250,000 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 2,250,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 337,500 Shares as provided in Section 2. The additional [ ] 337,500 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇Citigroup Global Markets Inc., ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ Barclays Capital Inc. and Company, Leerink Partners LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)198678, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formto

Introductory. Horizon Pharma, Inc.SQZ Biotechnologies Company, a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [●] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ [●] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [●] Shares as provided in Section 2. The additional [ [●] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” BofA Securities, Inc. (“BofA”), Evercore Group L.L.C. (“Evercore”) and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 249422 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formRule

Introductory. Horizon Pharma, Inc.Wave Life Sciences Ltd. (Company Registration Number: 201218209G), a Delaware corporation company incorporated under the laws of the Republic of Singapore (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (the “Underwriters”) (i) an aggregate of [ ] shares 15,789,475 of its common stockordinary shares, no par value $0.0001 per share (the “Shares”) and (ii) pre-funded warrants, substantially in the form of Exhibit C hereto, to purchase up to an aggregate of 2,631,578 Shares (the “Pre-Funded Warrants”). The [ ] 15,789,475 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 2,763,157 Shares as provided in Section 2. The additional [ ] 2,763,157 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” The Shares issuable upon exercise of the Pre-Funded Warrants are referred to herein as the “Warrant Shares.” The Offered Shares, the Pre-Funded Warrants and the Warrant Shares are collectively referred to herein as the “Offered Securities.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & CompanyLLC, Incorporated (“Stifel”)Leerink Partners LLC and BofA Securities, ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) Inc. have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered SharesSecurities. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such an “automatic shelf registration statement, ,” as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission defined under Rule 405 under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), on Form S-3ASR, File No. 333-283122, including any information deemed a base prospectus (the “Base Prospectus”) to be a part thereof at used in connection with the time public offering and sale of effectiveness pursuant to Rule 430A under the Securities ActOffered Securities. Such registration statement, is called as amended, including the “Registration Statement.” Any registration statement filed by financial statements, exhibits and schedules thereto, in the Company pursuant to Rule 462(b) form in which it became effective under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]1933, 2011 describing the Offered Shares as amended, and the offering thereof is called the “Preliminary Prospectus,” rules and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formregulations promulgated

Introductory. Horizon PharmaPreview Systems, Inc., a Delaware corporation (the “"Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ [___] shares (the "Firm Shares") ---------- of its common stockCommon Stock, par value $0.0001 0.0002 per share (the “"Common Shares"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [___] Common Shares (the "Option Shares") as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered "Shares.” ". BancBoston ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇▇▇▇ Inc., ▇▇▇▇ ▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇, SoundView Technology Group, Inc. and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) E*OFFERING Corp. have agreed to act as representatives of the several Underwriters (in such capacity, the “"Representatives”") in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 (File No. 333-168504333-[ ]), which contains a form of prospectus subject to be completion used in connection with the public offering and sale of the Offered Shares. Each such prospectus subject to completion used in connection with such public offering is called a "preliminary prospectus." Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, 1933 and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “"Registration Statement.” ". Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” ", and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The Such prospectus, in the formform first used by the Underwriters to confirm sales of the Shares, is called the "Prospectus." All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus or the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System ("▇▇▇▇▇"). The Company hereby confirms its agreements with the Underwriters as follows:

Introductory. Horizon PharmaBellicum Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [•] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ [•] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [•] Shares as provided in Section 2. The additional [ [•] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC Citigroup Global Markets Inc. (“JMPCiti”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 200328 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formform first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of

Introductory. Horizon Pharma, Inc.National Storage Affiliates Trust, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 4,500,000 common shares of its common stockbeneficial interest, par value $0.0001 0.01 per share (the “Shares)”) of the Company. The [ ] 4,500,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 675,000 Shares as provided in Section 2. The additional [ ] 675,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” Jefferies LLC (“Jefferies”) and ▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇▇▇ & Company, Incorporated Co. LLC (“Stifel”), ▇▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP▇▇▇▇▇▇▇”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S‑3, File No. 333-168504)333‑211570, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formto

Introductory. Horizon PharmaSesen Bio, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 22,222,223 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 22,222,223 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 3,333,333 Shares as provided in Section 2. The additional [ ] 3,333,333 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, Jefferies LLC (“CowenJefferies”) and JMP Securities Canaccord Genuity LLC (“JMPCanaccord”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)202676, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]May 30, 2011 2018 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formand

Introductory. Horizon Pharma, Inc.Immune Design Corp., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 4,800,000 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 4,800,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 720,000 Shares as provided in Section 2. The additional [ ] 720,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇ LLC (“Jefferies”), Leerink Partners LLC (“Leerink”) and ▇▇▇▇▇ & CompanyFargo Securities, Incorporated LLC (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMPFargo”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering offer and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)206324, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering offer and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called in connection with the “Rule 462(b) Registration Statement,” offer and from and after the date and time sale of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formthe

Introductory. Horizon PharmaProgenics Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 8,500,000 shares of its common stock, par value $0.0001 0.0013 per share (the “Shares”). The [ ] 8,500,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,275,000 Shares as provided in Section 2. The additional [ ] 1,275,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representative” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)176244, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]June 19, 2011 2013 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus supplement to the Base Prospectus in preliminary prospectus form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) ), together with the Base Prospectus, is called a “preliminary prospectus.” The prospectusAs used herein, in the formterm “Prospectus” shall mean the final prospectus supplement

Introductory. Horizon Pharma, Inc.First Potomac Realty Trust, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares of its common stockshares (the “Firm Shares”) of beneficial interest, par value $0.0001 .001 per share (the “Common Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Common Shares (the “Option Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇KeyBanc Capital Markets, ▇▇▇▇▇▇▇▇ & Company, Incorporated a division of McDonald Investments Inc. (“StifelKCM”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company is the sole general partner of First Potomac Realty Investment Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-11 (File No. 333-168504115958), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Such prospectus, 2011 describing in the Offered Shares and form first used by the offering thereof Underwriters to confirm sales of the Shares, is called the “Preliminary Prospectus,.” All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus or the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“E▇▇▇▇”). Each of the Company and the Preliminary Prospectus and any other preliminary prospectus that describes Operating Partnership hereby confirms its agreements with the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon Pharma, Inc.PPL Electric Utilities Corporation, a Delaware Pennsylvania corporation (the “Company”), proposes to issue and sell to sell, and the several underwriters Underwriters named in Schedule A Section 3 hereof (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act for whom you are acting as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with ), propose, severally and not jointly, to purchase, upon the offering terms and sale conditions set forth herein, $350,000,000 aggregate principal amount of the Offered SharesCompany’s First Mortgage Bonds, 4.75% Series due 2043 (the “Bonds”) to be issued under an Indenture, dated as of August 1, 2001, between the Company and The Bank of New York Mellon, as trustee thereunder (the “Trustee”), as previously amended and supplemented and as to be further amended and supplemented by Supplemental Indenture No. 15 thereto relating to the Bonds (the “Supplemental Indenture”), to be dated as of July 1, 2013 (such Indenture, as so supplemented, the “Indenture”). The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a an automatic shelf registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended180410-03) on Form S-3, including the financial statementsrelated preliminary prospectus or prospectus, exhibits which registration statement became effective upon filing under Rule 462(e) (“Rule 462(e)”) of the rules and schedules thereto, in the form in which it was declared effective by regulations of the Commission (the “Securities Act Regulations”) under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder amended (collectively, the “Securities Act”). Such registration statement covers the registration of the Bonds under the Securities Act. Promptly after the date of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430B (“Rule 430B”) of the Securities Act Regulations and paragraph (b) of Rule 424 (“Rule 424(b)”) of the Securities Act Regulations. Any information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be part of and included in such registration statement pursuant to Rule 430B is referred to as “Rule 430B Information.” Each prospectus used in connection with the offering of the Bonds that omitted Rule 430B Information (other than a “free writing prospectus” as defined in Rule 405 of the Securities Act Regulations that has not been approved in writing by the Company and the Representatives), including any information related prospectus supplement and the documents incorporated by reference therein pursuant to Item 12 of Form S-3, is herein called a “preliminary prospectus.” Such registration statement, at any given time, including the amendments or supplements thereto to such time, the exhibits and any schedules thereto at such time, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act at such time and the documents otherwise deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under or included therein by the Securities ActAct Regulations, is herein called the “Registration Statement.” Any registration statement filed The Registration Statement at the time it originally became effective is herein called the “Original Registration Statement.” The final prospectus in the form first furnished to the Underwriters for use in connection with the offering of the Bonds, including the related prospectus supplement and the documents incorporated by the Company reference therein pursuant to Rule 462(b) Item 12 of Form S-3 under the Securities Act as of the date hereof and any preliminary prospectuses that form a part thereof, is herein called the “Rule 462(b) Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (“▇▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is “contained,” and from and after “included” or “stated” in the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” , any preliminary prospectus or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by the Rule 462(b) Securities Act Regulations to be a part of or included in the Registration Statement. The , any preliminary prospectus dated [ ]or the Prospectus, 2011 describing as the Offered Shares case may be; and all references in this Agreement to amendments or supplements to the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and Registration Statement, any other preliminary prospectus that describes or the Offered Shares Prospectus shall be deemed to mean and the offering thereof and is used prior to include the filing of any document under the Prospectus Securities Exchange Act of 1934, as amended (as defined belowthe “Exchange Act”) which is called incorporated by reference in or otherwise deemed by the Securities Act Regulations to be a “preliminary prospectus.” The prospectus, part of or included in the formRegistration Statement, such preliminary prospectus or the Prospectus, as the case may be.

Introductory. Horizon Pharma, Inc.La Jolla Pharmaceutical Company, a Delaware California corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 2,550,000 shares of its common stock, par value $0.0001 per share (the “Shares”). The [ ] 2,550,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 382,500 Shares, as provided in Section 2. The additional [ ] 382,500 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated LLC (“StifelJefferies”), ) and ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)197092, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form)

Introductory. Horizon PharmaNuvelo, Inc., a Delaware Nevada corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A JMP Securities LLC (the “UnderwritersUnderwriter”) an aggregate of [ ] 10,000,000 shares (the “Firm Offered Shares”) of its common stockCommon Stock, par value $0.0001 0.001 per share (the “SharesCommon Stock”) in accordance with the terms and conditions set forth in this Underwriting Agreement (the “Agreement”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters Underwriter an option to purchase up to an additional [ ] Shares 1,500,000 shares (the “Optional Offered Shares”) of Common Stock, as provided in Section 22 (the “Purchase, Sale, and Delivery of the Offered Shares”). The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Offered Shares and, if and to the extent such option is exercised, the Optional Offered Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504106873), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits exhibits, and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act or the Securities Exchange Act of 1934, as amended and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]as amended or supplemented, 2011 describing including the documents incorporated by reference therein, in the form first used by the Underwriter to confirm sales of the Offered Shares and the offering thereof Shares, is called the “Preliminary Prospectus.” All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, the Prospectus or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“▇▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is “contained,” “included,” or “stated” in the Registration Statement or the Prospectus (and all other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Preliminary Registration Statement or the Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement or the Prospectus shall be deemed to mean and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to include the filing of any document under the Prospectus (as defined below) Exchange Act which is called a “preliminary prospectus.” The prospectus, or is deemed to be incorporated by reference in the formRegistration Statement or the Prospectus, as the case may be. The Company hereby confirms its agreements with the Underwriter as follows:

Introductory. Horizon PharmaThe stockholders of Red ▇▇▇▇▇ Gourmet Burgers, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (collectively, the “UnderwritersSelling Stockholders”) severally propose to sell to Wachovia Capital Markets, LLC (the “Underwriter”) an aggregate of [ ] 1,937,543 shares of its common stockCommon Stock, par value $0.0001 .001 per share (the “SharesCommon Stock”), of the Company. The [ ] Shares 1,937,543 shares of Common Stock to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option Selling Stockholders are collectively called the “Optional Common Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504115707), which contains a form of prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Common Shares, and has filed with, or shall promptly hereafter file with, the Commission a final prospectus supplement (the “Prospectus Supplement”) relating to the Common Shares pursuant to Rule 424(b) under the Securities Act of 1933, as amended (the “Securities Act”). As used herein, the term “Securities Act” shall mean to include the rules and regulations thereunder. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein as well as any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act or the Securities Exchange Act of 1934 and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” ”. Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” ”, and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The As used herein, the term “Prospectus” means the Base Prospectus and the Prospectus Supplement (as well as any preliminary prospectus dated [ ]supplement). All references in this Agreement to the Registration Statement, 2011 describing the Offered Shares Rule 462(b) Registration Statement, a preliminary prospectus, or the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and the offering thereof Retrieval System (“▇▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is called the “Preliminary Prospectuscontained,” “included” or “stated” in the Registration Statement or the Prospectus (and all other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Preliminary Registration Statement or the Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement or the Prospectus shall be deemed to mean and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to include the filing of any document under the Prospectus (as defined below) Exchange Act which is called a “preliminary prospectus.” The prospectus, or is deemed to be incorporated by reference in the formRegistration Statement or the Prospectus, as the case may be. The Company and each of the Selling Stockholders hereby confirm their respective agreements with the Underwriter as follows:

Introductory. Horizon Pharma, Inc.First Potomac Realty Trust, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 7,500,000 shares (the “Firm Shares”) of its common stockbeneficial interest, par value $0.0001 .001 per share (the “Common Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,125,000 Common Shares (the “Option Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered Shares.” ▇F▇▇▇▇▇, B▇▇▇▇ W▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenFBW”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company is the sole general partner of First Potomac Realty Investment Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-11 (File No. 333-168504107172), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Such prospectus, 2011 describing in the Offered Shares and form first used by the offering thereof Underwriters to confirm sales of the Shares, is called the “Preliminary Prospectus,.” All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus or the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“E▇▇▇▇”). Each of the Company and the Preliminary Prospectus and any other preliminary prospectus that describes Operating Partnership hereby confirms its agreements with the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon Pharma, Inc.Gladstone Land Corporation, a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (the “Underwriters”) an aggregate of [ ] 1,000,000 shares (the “Shares”) of its common stock6.375% Series A Cumulative Term Preferred Stock, par value $0.0001 0.001 per share (the “SharesPreferred Stock”). The [ ] Company is the indirect general partner of Gladstone Land Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The 1,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted agreed to sell to the Underwriters an option Underwriters, subject to purchase the terms and conditions stated herein, up to an additional [ ] 150,000 Shares as provided in Section 2to cover the over-allotment by the Underwriters, if any. The additional [ ] 150,000 Shares to be sold by the Company pursuant to such over-allotment option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such over-allotment option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇ ▇, ▇▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJanney”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A hereto, the term “Representative” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)194539, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formthe

Introductory. Horizon PharmaXeris Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [●] shares of its common stock, par value $0.0001 per share (the “Shares”). The [ [●] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [●] Shares as provided in Section 2. The additional [ [●] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, Jefferies LLC (“CowenJefferies”) and JMP Securities SVB Leerink LLC (“JMPSVB Leerink”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 333-[●] which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]prospectus, 2011 describing in the form first used by the Underwriters to confirm sales of the Offered Shares and or in the offering thereof form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formpreliminary

Introductory. Horizon Pharma, Inc.Gladstone Commercial Corporation, a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 1,400,000 shares (the “Shares”) of its common stockSeries C Cumulative Term Preferred Stock, par value $0.0001 0.001 per share (the “SharesSeries C Cumulative Term Preferred Stock”). The [ ] Company is the indirect general partner of Gladstone Commercial Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The 1,400,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 210,000 Shares as provided in Section 2. The additional [ ] 210,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ Jefferies & Company, Incorporated Inc. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representative” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)169290, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]January 23, 2011 2012 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formand

Introductory. Horizon Pharma▇▇▇▇▇▇▇▇▇▇ Electronics, Inc.Ltd., a Delaware corporation (the “"Company”"), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ ] 3,000,000 shares (the "Firm Shares") of its common stockCommon Stock, par value $0.0001 .05 per share (the “"Shares"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 450,000 Shares (the "Optional Shares"), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “"Offered Shares.” " ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated Inc. (“Stifel”"Jefferies"), ▇▇▇▇▇▇▇ and ▇▇▇▇▇ & Company, LLC (“Cowen”) L.L.C. and JMP Securities LLC (“JMP”) KeyBanc Capital Markets, a division of McDonald Investments Inc. have agreed to act as representatives of the several Underwriters (in such capacity, the “"Representatives”") in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 (File No. 333-168504113568), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “"Registration Statement.” " Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” " and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The Such prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares, is called the "Prospectus"; provided, however, if the Company has, with the consent of Jefferies, elected to rely upon Rule 434 under the Securities Act, the term "Prospectus" shall mean the Company's prospectus subject to completion (each, a "preliminary prospectus prospectus") dated [ ], 2011 describing 2004 (such preliminary prospectus is called the "Rule 434 preliminary prospectus"), together with the applicable term sheet (the "Term Sheet") prepared and filed by the Company with the Commission under Rules 434 and 424(b) under the Securities Act and all references in this Agreement to the date of the Prospectus shall mean the date of the Term Sheet. All references in this Agreement to (i) the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus, the Prospectus or the Term Sheet, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis, and Retrieval system ("▇▇▇▇▇") and (ii) the Prospectus shall be deemed to include the "electronic Prospectus" provided for use in connection with the offering of the Offered Shares and as contemplated by Section 3(k) of this Agreement. The Company hereby confirms its agreements with the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon PharmaCorium International, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [5,500,000] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ [5,500,000] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [825,000] Shares as provided in Section 2. The additional [ [825,000] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, Jefferies LLC (“CowenJefferies”) and JMP Securities Leerink Partners LLC (“JMPLeerink”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 194279 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]prospectus, 2011 describing in the form first used by the Underwriters to confirm sales of the Offered Shares and or in the offering thereof form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formpreliminary

Introductory. Horizon Pharma, Inc.National Storage Affiliates Trust, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A each of ▇▇▇▇▇▇ ▇▇▇▇▇▇▇ & Co. LLC (“▇▇▇▇▇▇ ▇▇▇▇▇▇▇”), Citigroup Global Markets Inc. (“Citigroup”), and BofA Securities, Inc. (“BofA”) (the “Underwriters”) an aggregate of [ ] 8,800,000 common shares of its common stockbeneficial interest, par value $0.0001 0.01 per share (the “Shares)”) of the Company. The [ ] 8,800,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,320,000 Shares as provided in Section 2. The additional [ ] 1,320,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)253663, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formfiling

Introductory. Horizon PharmaForma Therapeutics Holdings, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [●] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ [●] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [●] Shares as provided in Section 2. The additional [ [●] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated LLC (“StifelJefferies”), ▇▇▇▇▇ and Company, SVB Leerink LLC (“CowenSVB Leerink”) and JMP Credit Suisse Securities (USA) LLC (“JMPCredit Suisse”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 238783 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formcalled

Introductory. Horizon PharmaThis Agreement, Inc.effective as of the date first set forth above, a Delaware corporation amends and restates and replaces in its entirety the Sales Agency Agreement dated as of August 18, 2009 (the “CompanyPrior Sales Agreement”), proposes to issue between CHICAGO BRIDGE & IRON COMPANY N.V., a company with limited liability organized and sell to existing under the several underwriters named laws of The Netherlands, established in Schedule A (the “Underwriters”) an aggregate of [ ] shares of Amsterdam, having its common stockcorporate seat in The Hague and address at ▇▇▇▇▇▇▇▇▇▇▇▇ ▇▇, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition▇▇▇▇ ▇▇, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇ ▇▇▇▇▇, ▇▇▇ ▇▇▇▇▇▇▇▇▇▇▇ & (the “Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Credit Agricole Securities (USA) Inc., as sales agent (the “Agent”), pursuant to which the Company proposed to issue and sale up to 10,000,000 shares of the Company’s common stock, LLC par value Euro 0.01 per share (the “CowenCommon Stock”), and pursuant to which 2,448,683 shares of Common Stock were issued and sold (the “Sold Units”) thereunder. The Company proposes to issue and JMP Securities LLC sell from time to time through the Agent an offering of up to 7,551,317 shares (the “JMPShares”) have agreed of its Common Stock, by any method permitted by law deemed to act be an “at-the-market” offering as representatives defined in Rule 415 of the several Underwriters Securities Act (in such capacityas defined below), including, without limitation, sales made directly on the New York Stock Exchange (the “RepresentativesNYSE”), on any other existing trading market for the Shares or to or through a market maker (the “ATM Program”). It is understood and agreed by the parties hereto that: (a) in connection with the offering representations, warranties, agreements, indemnities and covenants applicable to the sale of the Offered SharesSold Units are limited to those as set forth in the Prior Sales Agreement, and (b) that the Shares offered hereby and hereunder are not governed by, and are in addition to and do not include the Sold Units offered pursuant to, the Prior Sales Agreement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a an automatic shelf registration statement on Form S-1 S-3 (File No. 333-168504160852), which contains a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of securities (the Offered “Shelf Securities”), including the Shares, to be issued from time to time by the Company. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by filed with the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including the financial statements, exhibits and schedules thereto and all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement As used herein, the term “Registration StatementProspectus” shall include mean the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing supplement to the Offered Base Prospectus that describes the Shares and the offering thereof is called pursuant to the ATM Program (the “Preliminary Prospectus Supplement”), together with the Base Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaAquinox Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [—] shares of its common stock, par value $0.0001 0.000001 per share (the “Shares”). The [ [—] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [—] Shares as provided in Section 2. The additional [ [—] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated LLC (“StifelJefferies”), ) and ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 193615 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Prospectus.” The preliminary prospectus dated [ ], 2011 [—] describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus in preliminary prospectus form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The As used herein, “Applicable Time” is [—][a.m.][p.m.] (New York City time) on [—]. As used herein, “free writing prospectus, ” has the meaning set forth in the formRule 405 under the

Introductory. Horizon PharmaMarinus Pharmaceuticals, Inc., Inc. a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 5,000,000 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 5,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 750,000 Shares as provided in Section 2. The additional [ ] 750,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated LLC (“StifelJefferies”), ▇▇▇▇▇ ) and CompanyRBC Capital Markets, LLC (“Cowen”) and JMP Securities LLC (“JMPRBC”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)206351, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]November 5, 2011 2015 describing the Offered Shares and the offering thereof is called (the “Preliminary Prospectus Supplement”), together with the Base Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaHanover Capital Mortgage Holdings, Inc., a Delaware Maryland corporation (the “Company”"COMPANY), proposes to issue and sell to the several underwriters named in Schedule A (the “"List of Underwriters”") attached hereto (collectively, the "UNDERWRITERS") an aggregate of [ ] 3,000,000 shares (the "FIRM OFFERED SHARES") of its common stockCommon Stock, par value $0.0001 .01 per share (the “Shares"COMMON STOCK") in accordance with the terms and conditions set forth in this Underwriting Agreement (the "AGREEMENT"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 450,000 shares (the "OPTIONAL OFFERED SHARES") of Common Stock, as provided in Section 22 ("Purchase, Sale, and Delivery of the Offered Shares"). The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Offered Shares and, if and to the extent such option is exercised, the Optional Offered Shares are collectively called the “Offered Shares"OFFERED SHARES.” " JMP Securities LLC ("JMP") and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”"REPRESENTATIVES") in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”"COMMISSION") a registration statement on Form S-1 S-2 (File No. 333-168504333-[___]), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits exhibits, and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”"SECURITIES ACT"), including all documents incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities ActAct or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (the "EXCHANGE ACT"), is called the “Registration Statement"REGISTRATION STATEMENT.” " Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule "RULE 462(b) Registration StatementREGISTRATION STATEMENT,” " and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The Such prospectus, in the formform first used by the Underwriters to confirm sales of the Offered Shares, is called the "PROSPECTUS;" provided, however, if the Company has, with the consent of JMP, elected to rely upon Rule 434 under the Securities Act, the term "PROSPECTUS" shall include the Company's prospectus subject to completion dated July ___, 2003 (each, a "PRELIMINARY PROSPECTUS"), together with the applicable term sheet (the "TERM SHEET") prepared and filed by the Company with the Commission under Rules 434 and 424(b) under the Securities Act and all references in this Agreement to the date of the Prospectus shall mean the date of the Term Sheet. All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus, the Prospectus or the Term Sheet, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System ("▇▇▇▇▇"). All references in this Agreement to financial statements and schedules and other information which is "contained," "included," or "stated" in the Registration Statement or the Prospectus (and all other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in the Registration Statement or the Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement or the Prospectus shall be deemed to mean and include the filing of any document under the Exchange Act which is incorporated by reference in the Registration Statement or the Prospectus, as the case may be. The Company hereby confirms its agreements with the Underwriters as follows:

Introductory. Horizon PharmaQTS Realty Trust, Inc., a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 5,750,000 shares of its Class A common stock, par value $0.0001 0.01 per share (the “Shares”); and GA QTS Interholdco, LLC (the “Selling Stockholder”) proposes to sell to the Underwriters an aggregate of 1,250,000 Shares. The [ ] 5,750,000 Shares to be sold by the Company and the 1,250,000 Shares to be sold by the Selling Stockholder are collectively called the “Firm Shares.” In addition, the Company Selling Stockholder has granted to the Underwriters an option to purchase up to an additional [ ] Shares 1,050,000 Shares, as provided in Section 2. The additional [ ] 1,050,000 Shares to be sold by the Company Selling Stockholder pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇Deutsche Bank Securities Inc. (“Deutsche Bank”), J▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC KeyBanc Capital Markets Inc. (“JMPKeyBanc”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)199848, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]June 1, 2011 2015 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus supplement to the Base Prospectus in preliminary prospectus form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) ), together with the Base Prospectus, is called a “preliminary prospectus.” The prospectus, in the form”

Introductory. Horizon PharmaIGM Biosciences, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [•] shares of its common stock, par value $0.0001 0.01 per share (the “Shares”). The [ [•] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [•] Shares as provided in Section 2. The additional [ [•] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇▇▇▇ LLC (“Jefferies”), ▇▇▇▇▇ ▇▇▇▇▇▇▇ & Co. (“▇▇▇▇▇ ▇▇▇▇▇▇▇”) and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 233365 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form)

Introductory. Horizon PharmaEvolus, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [●] shares of its common stock, par value $0.0001 0.00001 per share (the “Shares”). The [ [●] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [●] Shares as provided in Section 2. The additional [ [●] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” Cantor ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated Co. (“StifelCantor”), ▇▇▇▇▇ ) and Company, Mizuho Securities USA LLC (“Cowen”) and JMP Securities LLC (“JMPMizuho”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean the Representatives, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S‑1 (File No. 333-168504333‑222478), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Prospectus.” The preliminary prospectus dated [ [●], 2011 2018 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formin

Introductory. Horizon PharmaChesapeake Energy Corporation, Inc., a Delaware an Oklahoma corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (the “Underwriters”) 20,000,000 shares (“Firm Securities”) of its Common Stock (“Securities”) and also proposes to issue and sell to the Underwriters, at the option of the Underwriters, an aggregate of [ ] not more than 3,000,000 additional shares (“Optional Securities”) of its common stock, par value $0.0001 per share (the “Shares)Securities as set forth below. The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if Securities and to the extent such option is exercised, the Optional Shares Securities are herein collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“StifelSecurities”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed filed, in accordance with the provisions of the Securities Act of 1933, as amended, and the rules and regulations (the “Rules and Regulations”) thereunder (collectively, the “Act”), with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504130196) under the Act (the “registration statement”). Amendments to such registration statement, which contains a form of prospectus to be used in connection if necessary or appropriate, have been similarly prepared and filed with the public offering and sale of Commission in accordance with the Offered SharesAct. Such registration statement, as so amended, has become automatically effective under the Act upon filing with the Commission. Except where the context otherwise requires, “Registration Statement,” as used herein, means the registration statement, as amended at the time of such registration statement’s effectiveness for purposes of Section 11 of the Act, as such section applies to the respective Underwriters (the “Effective Time”), including (i) all documents filed as a part thereof or incorporated or deemed to be incorporated by reference therein and (ii) any information contained or incorporated by reference in a prospectus filed with the financial statementsCommission pursuant to Rule 424(b) under the Act, exhibits to the extent such information is deemed, pursuant to Rule 430B or Rule 430C under the Act, to be part of the registration statement at the Effective Time. The Company has furnished to the Underwriters, for use by the Underwriters and schedules theretoby dealers in connection with the offering of the Offered Securities, copies of one or more “preliminary prospectus supplements” relating to the Offered Securities. Except where the context otherwise requires, “Pre-Pricing Prospectus,” as used herein, means each such preliminary prospectus supplement relating to the Offered Securities, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”)so furnished, including any information deemed basic prospectus (whether or not in preliminary form) furnished by the Company to be a part thereof at the time Underwriters and attached to or used with such preliminary prospectus supplement. Except where the context otherwise requires, “Basic Prospectus,” as used herein, means any basic prospectus furnished by the Company to the Underwriters in connection with the offering of effectiveness pursuant the Offered Securities and attached to Rule 430A under or used with the Securities ActProspectus Supplement (as defined below). Except where the context otherwise requires, is called “Prospectus Supplement,” as used herein, means the “Registration Statement.” Any registration statement final prospectus supplement relating to the Offered Securities, filed by the Company with the Commission pursuant to Rule 462(b424(b) under the Securities Act is called on or before the “Rule 462(b) Registration Statement,” and from and second business day after the date hereof (or such earlier time as may be required under the Act), in the form furnished by the Company to the Underwriters for use by the Underwriters and time of filing by dealers in connection with the offering of the Rule 462(b) Registration Statement Offered Securities. Except where the term context otherwise requires, “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is as used prior to the filing of herein, means the Prospectus (as defined below) is called a “preliminary prospectusSupplement together with the Basic Prospectus attached to or used with the Prospectus Supplement.” The prospectus, in the form

Introductory. Horizon PharmaRedwood Trust, Inc., a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A attached hereto (the “Underwriters”) an aggregate of [ ] 1,000,000 shares (the “Firm Shares”) of its common stockCommon Stock, par value $0.0001 0.01 per share (the “Common Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 150,000 Common Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called (the “Optional Option Shares.” ”). The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called referred to herein as the “Offered Shares.” ▇▇▇▇▇▇, JMP Securities LLC and J▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed Inc. hereby agree to act as the representatives of the several Underwriters (in such capacity, the “Representatives”) of the Underwriters in connection with the public offering and sale of the Offered SharesFirm Shares and Option Shares contemplated by this Agreement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-16850425643), which contains a form of prospectus prospectus, subject to completion, to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein (the “Incorporated Documents”) and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act, ”) is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Such prospectus, 2011 describing in the Offered Shares and form first used by the offering thereof Underwriters to confirm sales of the Shares, is called the “Preliminary Prospectus.” All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“E▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is “contained,” “included” or “stated” in the Registration Statement or the Prospectus (and all other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Preliminary Registration Statement or the Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement or the Prospectus shall be deemed to mean and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to include the filing of any document under the Prospectus (as defined below) Exchange Act which is called a “preliminary prospectus.” The prospectus, or is deemed to be incorporated by reference in the formRegistration Statement or the Prospectus, as the case may be. The Company hereby confirms its agreements with the Underwriters as follows:

Introductory. Horizon PharmaAegerion Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 3,400,000 shares of its common stock, par value $0.0001 0.001 per share (the “SharesCommon Stock”). The [ ] Shares 3,400,000 shares of Common Stock to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 510,000 shares of Common Stock, as provided in Section 2. The additional [ ] Shares 510,000 shares of Common Stock to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇ & Company, Inc. (“Jefferies”) and ▇.▇. ▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMPJPMorgan”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 S-3 (File No. 333-168504177967), which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formRule

Introductory. Horizon PharmaFive Prime Therapeutics, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇ LLC, BMO Capital Markets Corp., and ▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and CompanyFargo Securities, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504)193491, which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formRegistration

Introductory. Horizon PharmaOrexigen Therapeutics, Inc., a Delaware corporation (the “Company”), proposes agrees with the several Underwriters named in Schedule A hereto (“Underwriters”) to issue and sell to the several underwriters named in Schedule A Underwriters 11,000,000 shares (the “UnderwritersFirm Securities”) an aggregate of [ ] shares of its common stock, par value $0.0001 0.001 per share (“Common Stock”) and also proposes to issue and sell to the Underwriters, at the option of the Underwriters, an aggregate of not more than 1,650,000 additional shares (“Shares)Optional Securities”) of its Common Stock as set forth below. The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if Securities and to the extent such option is exercised, the Optional Shares Securities are herein collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“StifelSecurities”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504183918), which contains a form of including the related preliminary prospectus to be used in connection with or prospectuses, covering the public offering and sale registration of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission Securities under the Securities Act of 1933, as amendedamended (the “1933 Act”). Promptly after execution and delivery of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430B (“Rule 430B”) of the rules and regulations promulgated thereunder of the Commission under the 1933 Act (collectively, the “1933 Act Regulations”) and paragraph (b) of Rule 424 (“Rule 424(b)”) of the 1933 Act Regulations. The information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be part of and included in such registration statement pursuant to Rule 430B is referred to as “Rule 430B Information.” Each prospectus used in connection with the offering of the Offered Securities Act”)that omitted the Rule 430B Information is herein called a “preliminary prospectus.” Such registration statement, at any given time, including any information all exhibits, financial schedules and the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the 1933 Act, as amended from time to time, and the documents otherwise deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Actor included therein by 1933 Act Regulations, is herein called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under of the Securities 1933 Act Regulations is called herein referred to as the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement such filing, if applicable, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary final prospectus dated [ ], 2011 describing in the form first furnished to the Underwriters for use in connection with the offering of the Offered Shares Securities, including the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the 1933 Act at the time of the execution of this Agreement and the offering thereof any preliminary prospectuses that form a part thereof, is herein called the “Preliminary Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (“▇▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is “contained,” and “included” or “stated” in the Preliminary Prospectus and Registration Statement, any other preliminary prospectus that describes or the Offered Shares Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by 1933 Act Regulations to be a part of or included in the offering thereof Registration Statement, any preliminary prospectus or the Prospectus, as the case may be; and is used prior all references in this Agreement to amendments or supplements to the Registration Statement, any preliminary prospectus or the Prospectus shall be deemed to mean and include the filing of any document under the Prospectus Securities Exchange Act of 1934, as amended (as defined belowthe “1934 Act”) which is called incorporated by reference in or otherwise deemed by 1933 Act Regulations to be a “preliminary prospectus.” The prospectus, part of or included in the formRegistration Statement, such preliminary prospectus or the Prospectus, as the case may be.

Introductory. Horizon PharmaRigel Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 16,000,000 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 16,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 2,400,000 Shares as provided in Section 2. The additional [ ] 2,400,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” Jefferies LLC (“Jefferies”) and ▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇▇▇ & Company, Incorporated Co. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMPPiper”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)223564, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]April 18, 2011 2018 describing the Offered Shares and the offering thereof is called (the “Preliminary Prospectus Supplement”), together with the Base Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaAdvanced Emissions Solutions, Inc., a Delaware corporation (the “Company”), proposes to issue and sell sell, pursuant to the terms of this Agreement, to the several underwriters named in Schedule A hereto (the “Underwriters,” or, each, an “Underwriter”) ), an aggregate of [ ] 600,000 shares of its common stock, $0.001 par value $0.0001 per share (the “Shares)Common Stock”) of the Company. The [ ] Shares aggregate of 600,000 shares so proposed to be sold by the Company are called is hereinafter referred to as the “Firm SharesStock.” In addition, the The Company has granted also proposes to sell to the Underwriters an option to purchase Underwriters, upon the terms and conditions set forth in Section 3 hereof, up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called 90,000 shares of Common Stock (the “Optional SharesStock”). The Firm Stock and the Optional Stock are hereinafter collectively referred to as the “Stock.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act is acting as representatives representative of the several Underwriters (and in such capacitycapacity is hereinafter referred to as the “Representative.” Pursuant to an Agreement and Plan of Merger, the “Representatives”) in connection with Company replaced ADA-ES, Inc. as the offering and sale of publicly-held corporation effective July 1, 2013. On July 3, 2013, the Offered Shares. The Company has prepared and filed with a post-effective amendment to the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (File No. 333ADA-168504)ES Registration Statement dated January 28, which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement2011, as amended, in order to assume the ADA-ES Registration Statement as a successor issuer. The SEC declared the post-effective amendment to such registration statement effective on July 18, 2013. As used herein, the terms “the Company”, “we”, “us” and “our” mean ADA-ES, Inc. for the periods through and including the financial statementsperiod ended June 30, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended2013, and Advanced Emissions Solutions, Inc. and its subsidiaries for the rules and regulations promulgated thereunder (collectivelyperiods after June 30, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement2013.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaHandheld Entertainment, Inc., a Delaware corporation (the “‘‘Company”), ’’) proposes to issue and sell to the several underwriters named in Schedule A I (the “‘‘Underwriters”’’) an aggregate of [ ] up to 3,800,000 shares (the ‘‘Firm Shares’’) of its common stockCommon Stock, par value $0.0001 per share (the “Shares‘‘Common Stock’’). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 570,000 shares (the ‘‘Optional Shares’’), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered ‘‘Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated ’’ Newbridge Securities Corporation (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”‘‘Newbridge’’) and JMP Securities LLC Pali Capital, Inc. (“JMP”‘‘Pali’’) have agreed to act as representatives of the several Underwriters (in such capacity, the “‘‘Representatives”’’) in connection with the offering and sale of the Offered Shares. The terms Representatives and Underwriters shall mean either the singular or plural as the context requires. The Company understands that the Underwriters propose to undertake a public offering of the Shares pursuant to the terms and conditions of this Agreement. The Company has prepared and filed with the Securities and Exchange Commission (the “‘‘Commission”’’) a registration statement on Form S-1 SB-2 (File No. 333-16850433550), which contains a form of prospectus to be used in connection with the public offering and sale related preliminary prospectus, or prospectuses, covering the registration of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission Shares under the Securities Act of 1933, as amendedamended (the ‘‘Securities Act’’). Promptly after execution and delivery of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430A (‘‘Rule 430A’’) of the rules and regulations promulgated thereunder of the Commission under the Securities Act (collectively, the “‘‘Securities Act”Act Regulations’’) and paragraph (b) of Rule 424 (‘‘Rule 424(b), including any ’’) of the Securities Act Regulations. The information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be a part thereof of such registration statement at the time of effectiveness it became effective pursuant to paragraph (b) of Rule 430A under is referred to as ‘‘Rule 430A Information.’’ Each prospectus that omitted the Securities ActRule 430A Information, that was used after such effectiveness and prior to the execution and delivery of this Agreement is herein called a ‘‘preliminary prospectus.’’ Such registration statement, including the exhibits, financial statements and any schedules thereto, at the time it became effective, and including the Rule 430A Information, is herein called the “‘‘Registration Statement.” ’’ Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities 1933 Act Regulations is called herein referred to as the “‘‘Rule 462(b) Registration Statement,” ’’ and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “‘‘Registration Statement” ’’ shall include the Rule 462(b) Registration Statement. The term ‘‘Prospectus’’ shall mean the final prospectus relating to the Shares that is first filed pursuant to Rule 424(b) under the Securities Act after the date and time that this Agreement is executed and delivered by the parties hereto (the ‘‘Execution Time’’) or, if no filing pursuant to Rule 424(b) under the Securities Act is required, shall mean the form of final prospectus relating to the Shares included in the Registration Statement at the effective date of the Registration Statement. The term ‘‘Statutory Prospectus’’ shall mean any preliminary prospectus dated [ ]prospectus, 2011 describing as amended or supplemented, relating to the Offered Shares and that is included in the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used Registration Statement immediately prior to the filing of the Prospectus Initial Sale Time (as defined belowherein), including any document incorporated by reference therein. All references in this Agreement to the Registration Statement, the Rule 462(b) is called a “Registration Statement, any preliminary prospectus, the Prospectus, or any amendments or supplements to any of the foregoing shall be deemed to include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (‘‘▇▇▇▇▇’’).” The prospectus, in the form

Introductory. Horizon PharmaDicerna Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 7,680,492 shares of its common stock, par value $0.0001 per share (the “Shares”). The [ ] 7,680,492 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,152,073 Shares as provided in Section 2. The additional [ ] 1,152,073 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated Citigroup Global Markets Inc. (“StifelCitigroup”), ▇▇▇▇▇ ) and Company, Leerink Partners LLC (“Cowen”) and JMP Securities LLC (“JMPLeerink”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)224989, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formof

Introductory. Horizon Pharma▇▇▇▇▇▇▇ Neurosciences, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 5,000,000 shares of its common stock, par value $0.0001 per share (the “Shares”). The [ ] 5,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 750,000 Shares as provided in Section 2. The additional [ ] 750,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” Citigroup Global Markets Inc. and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives Representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)205764, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]June 27, 2011 2017 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus supplement to the Base Prospectus in preliminary prospectus form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus), in together with the formBase

Introductory. Horizon Pharma, Legacy Healthcare Properties Trust Inc., a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [___] shares of its common stock, par value $0.0001 0.01 per share (the “Shares”). The [ [___] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [___] Shares as provided in Section 2. The additional [ [___] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇▇▇▇ & Company, Inc. (“Jefferies”) and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. Jefferies agrees that a portion of the Firm Shares to be purchased by it (the “Directed Shares”) shall be reserved for sale by Jefferies and its affiliates to certain eligible directors, officers and employees of the Company and persons having business relationships with the Company (collectively, the “Participants”), as part of the distribution of the Offered Shares by Jefferies (the “Directed Share Program”) subject to the terms of this Agreement, the applicable rules, regulations and interpretations of the Financial Industry Regulatory Authority, Inc. (“FINRA”) and all other applicable laws, rule and regulations. To the extent that such Directed Shares are not orally confirmed for purchase by the Participants by the end of the first business day after the date of this Agreement, such Directed Shares may be offered to the public by the Underwriters as part of the public offering contemplated hereby. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-11 (File No. 333-168504166448), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the forma

Introductory. Horizon Pharma, Inc.Gladstone Land Corporation, a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (the “Underwriters”) an aggregate of [ ] 1,150,000 shares (the “Shares”) of its common stockCommon Stock, par value $0.0001 0.001 per share (the “SharesCommon Stock”). The [ ] Company is the indirect general partner of Gladstone Land Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The 1,150,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted agreed to sell to the Underwriters an option Underwriters, subject to purchase the terms and conditions stated herein, up to an additional [ ] 172,500 Shares as provided in Section 2to cover the over-allotment by the Underwriters, if any. The additional [ ] 172,500 Shares to be sold by the Company pursuant to such over-allotment option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such over-allotment option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇ ▇, ▇▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJanney”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A hereto, the term “Representative” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)194539, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form)

Introductory. Horizon Pharma, Inc.Immune Design Corp., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [_______] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ [__________] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [_______] Shares as provided in Section 2. The additional [ [________] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & CompanyLLC, Incorporated (“Stifel”), Leerink Partners LLC and ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S‑1, File No. 333-168504), 203241 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formform first used by the Underwriters to confirm sales of the

Introductory. Horizon Pharma, Inc.Aurora Oil & Gas Corporation, a Delaware Utah corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 16,000,000 shares of its common stockstock (the “Primary Shares”), par value $0.0001 .01 per share (the “Shares”). The [ ] Shares to be sold by , of the Company are called and Rubicon Master Fund, a stockholder of the Company (the “Selling Stockholder”) proposes to sell to the Underwriters an aggregate of 8,000,000 Shares (the “Secondary Shares” and together with the Primary Shares, the “Firm Shares.” ”). In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 3,600,000 Shares (the “Optional Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” J▇▇▇▇▇▇, ▇ R▇▇▇ & Company L.L.C. (“JRCO”), KeyBanc Capital Markets, a Division of McDonald Investments, Inc. and M▇▇▇▇▇ ▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) Inc. have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 SB-2 (File No. 333-168504137176), which contains a form of prospectus and amendments thereto, and related preliminary prospectuses to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the prospectus, financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formterm

Introductory. Horizon PharmaEl Pollo Loco Holdings, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [—] shares of its common stock, par value $0.0001 0.10 per share (the “Shares”). The [ [—] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [—] Shares as provided in Section 2. The additional [ [—] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇ LLC (“Jefferies”) and ▇▇▇▇▇▇ ▇▇▇▇▇▇▇ & Company, Incorporated Co. LLC (“Stifel”), ▇▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP▇▇▇▇▇▇▇”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 197001 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Prospectus.” The preliminary prospectus dated [ [—], 2011 2014 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus in preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaThe Active Network, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares (the “Firm Shares”) of its common stockCommon Stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares (the “Optional Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares Shares, are collectively called the “Offered Shares.” Jefferies & Company, Inc. (“Jefferies”) and ▇▇ ▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company+ Co, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (File No. 333-168504333-[ ]), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Such prospectus, 2011 describing in the form first used by the Underwriters to confirm sales of the Offered Shares and the offering thereof Shares, is called the “Preliminary Prospectus,.” and All references in this Agreement to the Preliminary Prospectus and any other Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus that describes or the Offered Shares and the offering thereof and is used prior Prospectus, or any amendments or supplements to the filing any of the Prospectus foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis, and Retrieval system (“▇▇▇▇▇”). The Company hereby confirms its agreements with the Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon PharmaFive Prime Therapeutics, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇ LLC, BMO Capital Markets Corp., and ▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and CompanyFargo Securities, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 190194 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form)

Introductory. Horizon Pharma, Inc.Compass International Services Corporation, a Delaware corporation (the “"Company”"), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ ] 4,100,000 shares (the "Firm Common Shares") of its common stockCommon Stock, par value $0.0001 .01 per share (the “Shares"Common Stock"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 615,000 shares (the "Optional Common Shares") of Common Stock, as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Common Shares and, if and to the extent such option is exercised, the Optional Common Shares are collectively called the “Offered "Common Shares.” ". NationsBanc ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & CompanySecurities, Incorporated Inc. (“Stifel”), "NationsBanc ▇▇▇▇▇▇▇▇▇▇") and ▇▇▇▇▇▇ and CompanyBrothers, LLC (“Cowen”) and JMP Securities LLC (“JMP”) Inc. have agreed to act as representatives of the several Underwriters (in such capacity, the “"Representatives”") in connection with the offering and sale of the Offered Common Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 (File No. 333-16850437205), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Common Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, 1933 and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “"Registration Statement.” ". Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” ", and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The Such prospectus, in the formform first used by the Underwriters to confirm sales of the Common Shares, is called the "Prospectus"; provided, however, if the Company has, with the

Introductory. Horizon Pharma, Moog Inc., a Delaware New York corporation (the “"Company”"), proposes to issue and sell to the several underwriters named in Schedule A Banc of America Securities LLC (the “Underwriters”"Underwriter") an U.S.$150,000,000 aggregate principal amount of [ ] shares of its common stock, par value $0.0001 per share the Company's 6.250% Senior Subordinated Notes due 2015 (the “Shares"Securities"). The [ ] Shares Securities are to be sold by issued pursuant to an Indenture, to be dated January 10, 2005 between the Company are called and JPMorgan Chase Bank, N.A., as indenture trustee (the “Firm Shares.” In addition"Trustee") (collectively, the "Indenture"). Securities issued in book-entry form will be issued in the name of Cede & Co., as nominee of The Depository Trust Company has granted ("DTC") pursuant to a letter of representations, to be dated as of the Underwriters an option to purchase up to an additional [ ] Shares Delivery Date (as provided defined in Section 2. The additional [ ] Shares to be sold by 3) (the Company pursuant to such option are collectively called "DTC Letter of Representations"), among the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercisedCompany, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ Trustee and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered SharesDTC. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 S-3 (File No. 333-168504), which contains a form 113698) for the registration of prospectus to be used in connection with debt securities (including the public offering and sale Securities) of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission Company under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed and the offering thereof from time to be a part thereof at the time of effectiveness pursuant to in accordance with Rule 430A 415 under the Securities Act. Such registration statement has been declared effective by the Commission. Such registration statement, as so amended, if applicable, including the exhibits and schedules thereto, and including all documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3, prior to the execution of this Agreement, is called the “"Registration Statement.” ". Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” ", and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary final prospectus dated [ ], 2011 describing the Offered Shares and the final prospectus supplement relating to the offering thereof of the Securities, in the form first furnished to the Underwriter by the Company for use in connection with the offering of the Securities, including all documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3, prior to the execution of this Agreement, is called the “Preliminary "Prospectus,” and the Preliminary Prospectus and ". A "preliminary prospectus" shall be deemed to refer to any other preliminary prospectus that describes omitted information to be included upon pricing in a form of prospectus filed with the Offered Shares Commission pursuant to Rule 424(b) under the Securities Act and the offering thereof and is was used prior to the execution and delivery of this Agreement. All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus, the Prospectus or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System ("E▇▇▇▇"). The Company hereby confirms its engagement of Lazard Frères & Co. LLC to render services as "qualified independent underwriter" within the meaning of Rule 2720 of the Conduct Rules of the NASD with respect to the offering and sale of the Securities. Lazard Frères & Co. LLC, solely in its capacity as qualified independent underwriter and not otherwise, is referred to herein as the "QIU". The yield at which the Securities will be sold to the public shall not be lower than the yield recommended by the QIU. All references in this Agreement to financial statements and schedules and other information which is "contained", "included" or "stated" (and all other references of like import) in the Registration Statement, a preliminary prospectus or the Prospectus shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Registration Statement, a preliminary prospectus or the Prospectus, as the case may be, prior to the execution of this Agreement; and all references in this Agreement to amendments or supplements to the Registration Statement, a preliminary prospectus or the Prospectus shall be deemed to mean and include the filing of any document under the Prospectus Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (as defined belowcollectively, the "Exchange Act") which is called a “preliminary prospectus.” The prospectus, or is deemed to be incorporated by reference in the formRegistration Statement, a preliminary prospectus or the Prospectus, as the case may be, after the execution of this Agreement. In connection with the offering of the Securities, the Company expects to use the net proceeds from the sale of the Securities for repayment of debt obligations as described in the preliminary prospectus under "Use of Proceeds." The Company hereby confirms its agreements with the Underwriter and the QIU as follows:

Introductory. Horizon PharmaCorium International, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 4,000,000 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 4,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 600,000 Shares as provided in Section 2. The additional [ ] 600,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities Leerink Partners LLC (“JMPLeerink”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)204025, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]August 3, 2011 2015 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaCodex DNA, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [l] shares of its common stock, par value $0.0001 per share (the “Shares”). The [ [l] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [l] Shares as provided in Section 2. The additional [ [l] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated LLC (“StifelJefferies”), ) and ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 256644 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Company has prepared and filed, 2011 describing in accordance with Section 12 of the Offered Shares Securities Exchange Act of 1934, as amended, and the offering thereof is called rules and regulations promulgated thereunder (collectively, the “Preliminary Prospectus,” and Exchange Act”), a registration statement (as amended, the Preliminary Prospectus and any other preliminary prospectus that describes “Exchange Act Registration Statement”) on Form 8-A (File No. 001-[l]) under the Offered Shares and the offering thereof and is used prior Exchange Act to the filing register, under Section 12(b) of the Prospectus (as defined below) is called a “preliminary prospectus.” Exchange Act, the class of securities consisting of the Shares. The prospectus, in the formform first used by the Underwriters

Introductory. Horizon Pharma, Inc.CECO Environmental Corp., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 1,000,000 shares of its common stock, par value $0.0001 0.01 per share (the “Shares”), and the stockholders of the Company named in Schedule B (collectively, the “Selling Stockholders”) severally propose to sell to the Underwriters an aggregate of 2,348,166 Shares. The [ ] 1,000,000 Shares to be sold by the Company and the 2,348,166 Shares to be sold by the Selling Stockholders are collectively called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 502,250 Shares (the “Optional Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated Co. Inc. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenOppenheimer”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504142052), which contains a form of prospectus and amendments thereto, and related preliminary prospectuses to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the prospectus, financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]prospectus, 2011 describing in the form first used by the Underwriters to confirm sales of the Offered Shares and or in the offering thereof form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Preliminary Prospectus,.” and the Preliminary Prospectus and any other Any preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, included in the formRegistration Statement or filed with the

Introductory. Horizon Pharma, Inc.ATP Oil & Gas Incorporation, a Delaware Texas corporation (the “Company”), proposes to issue confirms its agreement with ▇▇▇▇▇▇▇ ▇▇▇▇ & Company L.L.C. and sell to the several underwriters named in Schedule A ▇▇▇▇▇▇ ▇▇▇▇ Incorporated (the “Underwriters”) ), with respect to the issue and sale by the Company and the purchase by the Underwriters of an aggregate of [ ] 5,000,000 shares (the “Firm Shares”) of its the common stock, par value $0.0001 0.001 per share (the “Shares”), of the Company. The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, T. ▇▇▇▇ ▇▇▇▇▇▇▇ (the Company “Selling Shareholder”) has granted to the Underwriters Underwriter an option to purchase up to an additional [ ] 750,000 Shares (the “Optional Shares”), as provided in Section 23. The additional [ ] Firm Shares to be sold purchased by the Company pursuant to such option are collectively called Underwriters, together with the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercisedpurchased, the Optional Shares are hereinafter collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 S-3 (File No. 333-168504146588), which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, prospectus and exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Any registration statement The prospectus supplement to be filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and promptly after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 hereof describing the Offered Shares and the offering thereof is called (the “Preliminary Prospectus Supplement”), together with the Base Prospectus,” and , in the Preliminary Prospectus and any other preliminary prospectus that describes form first made available to the Underwriters by the Company to confirm sales of the Offered Shares and or in the offering thereof and is used prior form first made available to the filing Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Prospectus (Securities Act, is referred to herein as defined below) is called a the “preliminary prospectusProspectus.” The As used herein, “Applicable Time” is 11:00 AM (New York time) on November 15, 2007. As used herein, “free writing prospectus” has the meaning set forth in Rule 405 under the Securities Act, in the formand “Time of Sale Prospectus” means the

Introductory. Horizon Pharma, ALX Oncology Holdings Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) (i) an aggregate of [ ] 76,979,112 shares (the “Shares”) of its common stock, par value $0.0001 0.001 per share (the “SharesCommon Stock”) and (ii) pre-funded warrants of the Company to purchase an aggregate of 18,574,120 Shares (the “Pre-Funded Warrants”). The [ ] 76,979,112 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and together with the Pre-Funded Warrants, are referred to the extent such option is exercised, the Optional Shares are collectively called herein as the “Offered SharesSecurities.” ▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇▇▇ & Company, Incorporated Co. (“Stifel”), ▇▇▇▇▇ ▇▇▇▇▇▇▇”), UBS Securities LLC (“UBS”) and Company▇▇▇▇▇ Fargo Securities, LLC (“Cowen”) and JMP Securities LLC (“JMP▇▇▇▇▇ Fargo”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Securities. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. As used herein, “Warrant Shares” means the Shares issuable upon exercise of the Pre-Funded Warrants. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)285620, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered SharesSecurities in the form first used to confirm sales of the Offered Securities (or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act). Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formpromulgated

Introductory. Horizon PharmaPresbia PLC, Inc., a Delaware corporation an Irish incorporated public limited company (registered no. 539137) (the “Company”), proposes proposes, subject to the terms and conditions set forth herein, to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [—] shares of its common stockordinary shares, par value $0.0001 .001 per share (the “Shares”). The [ [—] Shares to be sold issued by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase subscribe for up to an additional [ [—] Shares as provided in Section 2. The additional [ [—] Shares to be sold by the Company issued pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering offering, issue and onward sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representative” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 333- 194713 which contains a form of prospectus to be used in connection with the public offering and sale the issue of the Offered Shares. Such registration statement, as amended, including the financial statements, statements and exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and issue of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The Company has prepared and filed, in accordance with Section 12 of the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder (collectively, the “Exchange Act”), a registration statement (as amended, the “Exchange Act Registration Statement”) on Form 8-A (File No. [—]) under the Exchange Act to register, under Section 12(b) of the Exchange Act, the class of securities consisting of the Shares. The prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Prospectus.” The preliminary prospectus dated [ ], 2011 [—] describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus in preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon Pharma, Inc.Whitestone REIT, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (collectively, the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.,” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares which term shall also include any underwriter hereinafter substituted as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and9 hereof), if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇for whom ▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇. ▇▇▇▇▇ and Company, LLC & Co. Incorporated (“CowenBaird”) and JMP Securities LLC (“JMP”) have agreed to act are acting as representatives of the several Underwriters (in such capacity, if and as applicable, the “Representatives”), with respect to (i) in connection with the offering sale by the Company and sale the purchase by the Underwriters, acting severally and not jointly, of 4,000,000 common shares of beneficial interest, par value $0.001 per share of the Offered Company (the “Common Shares”) and (ii) the grant by the Company to the Underwriters, acting severally and not jointly, of the option described in Section 2 hereof to purchase all or any part of 600,000 additional Common Shares to cover over-allotments, if any. The aforesaid 4,000,000 shares of Common Stock (the “Firm Shares”) to be purchased by the Underwriters and all or any part of the 600,000 Common Shares subject to the option described in Section 2 hereof (the “Optional Shares”) are herein called, collectively, the “Shares.” The Company understands that the Underwriters propose to make a public offering of the Shares as soon as the Representatives deem advisable after this Agreement has been executed and delivered. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 S-3 (File No. 333-168504), which contains a form of prospectus to be used in connection with 182667) covering the public offering and sale of the Offered Shares. Such registration statement, as amendedcertain securities, including the financial statementsShares, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amendedamended (the “Securities Act”), and the rules and regulations promulgated thereunder (collectively, the “Securities ActAct Regulations”), which shelf registration statement was declared effective by the Commission on July 25, 2012. Such registration statement, as of any time, means such registration statement as amended by any post-effective amendments thereto to such time, including the exhibits and any information schedules thereto at such time, the documents incorporated or deemed to be incorporated by reference therein at such time pursuant to Item 12 of Form S-3 under the Securities Act and the documents otherwise deemed to be a part thereof at as of such time pursuant to Rule 430B under the Securities Act Regulations (“Rule 430B”), is referred to herein as the “Registration Statement;” provided, however, that the “Registration Statement” without reference to a time means such registration statement as amended by any post-effective amendments thereto as of the time of effectiveness the first contract of sale for the Shares, which time shall be considered the “new effective date” of such registration statement with respect to the Shares within the meaning of paragraph (f)(2) of Rule 430B, including the exhibits and schedules thereto as of such time, the documents incorporated or deemed incorporated by reference therein at such time pursuant to Item 12 of Form S-3 under the Securities Act and the documents otherwise deemed to be a part thereof as of such time pursuant to the Rule 430A 430B. Each preliminary prospectus used in connection with the offering of the Shares, including the documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant are collectively referred to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (herein as defined below) is called a “preliminary prospectus.” Promptly after execution and delivery of this Agreement, the Company will prepare and file a final prospectus relating to the Shares in accordance with the provisions of Rule 424(b) under the Securities Act Regulations (“Rule 424(b)”). The final prospectus, in the formform filed with the Commission pursuant to Rule 424(b) in connection with the offering of the Shares, including the documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, are collectively referred to herein as the “Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendments or supplements to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (or any successor system)(“▇▇▇▇▇”). As used in this Agreement:

Introductory. Horizon PharmaMedpace Holdings, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [●] shares of its common stock, par value $0.0001 [●] per share (the “Shares”). The [ [●] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [●] Shares as provided in Section 2. The additional [ [●] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Credit Suisse Securities (USA) LLC (“JMPCredit Suisse”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 333-[●] which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Prospectus.” The preliminary prospectus dated [ [●], 2011 2016, describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus in preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon Pharma, Inc.PPL Electric Utilities Corporation, a Delaware Pennsylvania corporation (the “Company”), proposes to issue and sell to sell, and the several underwriters Underwriters named in Schedule A Section 3 hereof (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act for whom you are acting as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with ), propose, severally and not jointly, to purchase, upon the offering terms and sale conditions set forth herein, $350,000,000 aggregate principal amount of the Offered SharesCompany’s First Mortgage Bonds, 4.150% Series due 2045 (the “Bonds”) to be issued under an Indenture, dated as of August 1, 2001, between the Company and The Bank of New York Mellon, as trustee thereunder (the “Trustee”), as previously amended and supplemented and as to be further amended and supplemented by Supplemental Indenture No. 17 thereto relating to the Bonds (the “Supplemental Indenture”), to be dated as of October 1, 2015 (such Indenture, as so supplemented, the “Indenture”). The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a an automatic shelf registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended202290-01) on Form S-3, including the financial statementsrelated preliminary prospectus or prospectus, exhibits which registration statement became effective upon filing under Rule 462(e) (“Rule 462(e)”) of the rules and schedules thereto, in the form in which it was declared effective by regulations of the Commission (the “Securities Act Regulations”) under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder amended (collectively, the “Securities Act”). Such registration statement covers the registration of the Bonds under the Securities Act. Promptly after the date of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430B (“Rule 430B”) of the Securities Act Regulations and paragraph (b) of Rule 424 (“Rule 424(b)”) of the Securities Act Regulations. Any information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be part of and included in such registration statement pursuant to Rule 430B is referred to as “Rule 430B Information.” Each prospectus used in connection with the offering of the Bonds that omitted Rule 430B Information (other than a “free writing prospectus” as defined in Rule 405 of the Securities Act Regulations that has not been approved in writing by the Company and the Representatives), including any information related prospectus supplement and the documents incorporated by reference therein pursuant to Item 12 of Form S-3, is herein called a “preliminary prospectus.” Such registration statement, at any given time, including the amendments or supplements thereto to such time, the exhibits and any schedules thereto at such time, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act at such time and the documents otherwise deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under or included therein by the Securities ActAct Regulations, is herein called the “Registration Statement.” Any registration statement filed The Registration Statement at the time it originally became effective is herein called the “Original Registration Statement.” The final prospectus in the form first furnished to the Underwriters for use in connection with the offering of the Bonds, including the related prospectus supplement and the documents incorporated by the Company reference therein pursuant to Rule 462(b) Item 12 of Form S-3 under the Securities Act as of the date hereof and any preliminary prospectuses that form a part thereof, is herein called the “Rule 462(b) Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval (“▇▇▇▇▇”) system. All references in this Agreement to financial statements and schedules and other information which is “contained,” and from and after “included” or “stated” in the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” , any preliminary prospectus or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by the Rule 462(b) Securities Act Regulations to be a part of or included in the Registration Statement. The , any preliminary prospectus dated [ ]or the Prospectus, 2011 describing as the Offered Shares case may be; and all references in this Agreement to amendments or supplements to the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and Registration Statement, any other preliminary prospectus that describes or the Offered Shares Prospectus shall be deemed to mean and the offering thereof and is used prior to include the filing of any document under the Prospectus Securities Exchange Act of 1934, as amended (as defined belowthe “Exchange Act”) which is called incorporated by reference in or otherwise deemed by the Securities Act Regulations to be a “preliminary prospectus.” The prospectus, part of or included in the formRegistration Statement, such preliminary prospectus or the Prospectus, as the case may be.

Introductory. Horizon Pharma, Inc.First Potomac Realty Trust, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares 3,000,000 of its common stockshares (the “Firm Shares”) of beneficial interest, par value $0.0001 .001 per share (the “Common Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 450,000 Common Shares (the “Option Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇KeyBanc Capital Markets, ▇▇▇▇▇▇▇▇ & Company, Incorporated a division of McDonald Investments Inc. (“StifelKCM”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company is the sole general partner of First Potomac Realty Investment Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed a registration statement on Form S-3 (File No. 333-120821), which contains a form of prospectus to be a part thereof at used in connection with the time public offering and sale of effectiveness pursuant the Shares (the “Base Prospectus”). Such registration statement, herein referred to Rule 430A under the Securities Act, is called as the “Registration Statement.,” Any registration statement shall be deemed to include all information omitted therefrom in reliance upon Rules 430A or 430B under the Securities Act and all information incorporated by reference therein. The form of final prospectus relating to the Shares first filed by the Company with the Commission pursuant to Rule 462(b424(b) under the Securities Act is called herein referred to as the “Rule 462(bProspectus.” The Base Prospectus, as supplemented by any preliminary prospectus (including any preliminary prospectus supplement) relating to the Shares used prior to the date hereof is herein referred to as a “Preliminary Prospectus.” Any reference herein to the Registration Statement,” , any Preliminary Prospectus or the Prospectus or to any amendment or supplement to any of the foregoing documents shall be deemed to refer to and from include any documents incorporated by reference therein and any supplements or amendments thereto, filed with the Commission after the date and time of filing of the Prospectus under Rule 462(b424(b) Registration Statement under the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Securities Act, 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing termination of the Prospectus (offering of the Shares by the Underwriters. Each of the Company and the Operating Partnership hereby confirms its agreements with the Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon Pharma, Inc.Caribou Holding Company Limited, a Delaware corporation Cayman Island company (the “CompanySelling Shareholder”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 5,000,000 shares of its common stock, par value $0.0001 0.01 per share (the “Shares”) of Caribou Coffee Company Inc., a Minnesota corporation (the “Company”). The [ ] 5,000,000 Shares to be sold by the Company Selling Shareholder are called the “Firm Shares.” In addition, the Company Selling Shareholder has granted to the Underwriters an option to purchase up to an additional [ ] Shares 750,000 Shares, all as provided in Section 2. The additional [ ] 750,000 Shares to be sold by the Company Selling Shareholder pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ Jefferies & Company, Incorporated Inc. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives Representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 S-3 (File No. 333-168504170634), which contains and has prepared a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Such prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Registration StatementProspectus.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]December 6, 2011 2010 describing the Offered Shares and the offering thereof thereof, together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus supplement to the Base Prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formOffered

Introductory. Horizon PharmaLombard Medical, Inc., a Delaware corporation Cayman Islands company (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [—] shares of its common stockthe Company’s ordinary shares, par value $0.0001 [—] per share (the “Shares”). The [ [—] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [—] Shares Shares, all as provided in Section 2. The additional [ [—] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC Barclays Capital Inc. (“JMPBarclays”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (F-1, File No. 333-168504), 333-[—] which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]prospectus, 2011 describing in the form first used by the Underwriters to confirm sales of the Offered Shares and or in the offering thereof form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formpreliminary

Introductory. Horizon PharmaKeynote Systems, Inc., a Delaware California corporation (the “"Company”"), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ ] 1,750,000 shares of its common stockCommon ---------- Stock, par value $0.0001 0.001 per share (the “"Common Shares"); and the shareholders of the Company identified in Schedule B as "Principal Selling Shareholders" (the ---------- "Principal Selling Shareholders") and the shareholders of the Company identified in Schedule B as "Other Selling Shareholders" (the "Other Selling Shareholders" ---------- and, collectively, together with the Principal Selling Shareholders, the "Selling Shareholders") propose to sell to the Underwriters an aggregate of 3,750,000 Common Shares. The [ ] 1,750,000 Common Shares to be sold by the Company and the 3,750,000 Common Shares to be sold by the Selling Shareholders are collectively called the “"Firm Shares.” ". In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 825,000 Common Shares (the "Option Shares"), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares Option Shares, are collectively called the “Offered "Shares.” ". FleetBoston ▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇ Inc., ▇▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ LLC, ▇▇▇▇ ▇▇▇▇▇▇▇▇ Incorporated, and CompanySoundView Technology Group, LLC (“Cowen”) and JMP Securities LLC (“JMP”) Inc. have agreed to act as representatives of the several Underwriters (in such capacity, the “"Representatives”") in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 (File No. 333-16850494651), which contains a form of prospectus prospectus, subject to completion, to be used in connection with the public offering and sale of the Offered Shares. Each such prospectus, subject to completion, used in connection with such public offering is called a "preliminary prospectus." Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, 1933 and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “"Registration Statement.” ". Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” ", and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The Such prospectus, in the formform first used by the Underwriters to confirm sales of the Shares, is called the "Prospectus." All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus, the Prospectus or the Term Sheet, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System ("▇▇▇▇▇"). The Company and each of the Selling Shareholders hereby confirms their agreements with the Underwriters as follows:

Introductory. Horizon Pharma, Inc.Affimed N.V., a Delaware corporation company incorporated under the laws of the Netherlands (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares of its 5,000,000 common stockshares, par value $0.0001 €0.01 per share (the “Common Shares”). The [ ] 5,000,000 Common Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 750,000 Common Shares as provided in Section 2. The additional [ ] 750,000 Common Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, J▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities Leerink Partners LLC (“JMPLeerink”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (F-1, File No. 333-168504), 203638 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form)

Introductory. Horizon Pharma, Inc.Egain Communications Corporation, a Delaware corporation (the “"Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ ] 5,000,000 shares (the "Firm ---------- Shares") of its common stockCommon Stock, par value $0.0001 0.001 per share (the “"Common Shares"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 750,000 Common Shares (the "Option Shares") as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered "Shares.” ". BancBoston ▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇ Inc., ▇▇▇▇▇▇▇▇▇, ▇▇▇▇▇▇ & ▇▇▇ & Company▇▇▇▇▇▇, Incorporated (“Stifel”), Inc. and ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) ▇▇▇▇▇ ▇▇▇▇▇▇ & Co. have agreed to act as representatives of the several Underwriters (in such capacity, the “"Representatives”") in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 (File No. 333-16850483439), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, 1933 and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “"Registration Statement.” ". Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” ", and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The Such prospectus, in the formform first used by the Underwriters to confirm sales of the Shares, is called the "Prospectus"; provided, however, if the Company has, with the consent of BancBoston ▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇ Inc., elected to rely upon Rule 434 under the Securities Act, the

Introductory. Horizon PharmaMercury Computer Systems, Inc., a Delaware Massachusetts corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 4,850,000 shares of its common stock, par value $0.0001 0.01 per share (the “Firm Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 727,500 shares of its common stock, par value $0.01 per share, as provided in Section 2. The additional [ ] Shares 727,500 shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” The Company’s common stock, par value $0.01 per share, is referred to herein as the “Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated Inc. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities Lazard Capital Markets LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 S-3 (File No. 333-168504158847), which contains and has prepared a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formfiling

Introductory. Horizon Pharma, Inc.Gladstone Commercial Corporation, a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (the “Underwriters”) an aggregate of [ ] 1,100,000 shares (the “Shares”) of its common stockCommon Stock, par value $0.0001 0.001 per share (the “SharesCommon Stock”). The [ ] Company is the indirect general partner of Gladstone Commercial Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The 1,100,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 165,000 Shares as provided in Section 2. The additional [ ] 165,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A hereto, the term “Representative” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)169290, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]April 23, 2011 2013 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus supplement to the Base Prospectus in preliminary prospectus form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus), in together with the formBase

Introductory. Horizon PharmaDicerna Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 2,750,000 shares of its common stock, par value $0.0001 per share (the “Shares”). The [ ] 2,750,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 412,500 Shares as provided in Section 2. The additional [ ] 412,500 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, Jefferies LLC (“CowenJefferies”) and JMP Securities Leerink Partners LLC (“JMPLeerink”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)202687, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amendedamended (but excluding the preliminary prospectus dated March 12, 2015 relating to the sale of up to 2,500,000 shares of Common Stock through ▇▇▇▇▇ and Company LLC included in such registration statement), including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formall documents

Introductory. Horizon Pharma, Inc.NewLink Genetics Corporation, a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 5,000,000 shares of its common stock, par value $0.0001 0.01 per share (the “Shares”). The [ ] 5,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 750,000 Shares as provided in Section 2. The additional [ ] 750,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇▇ Lynch, Pierce, ▇▇▇▇▇▇ & ▇▇▇▇▇ Incorporated (“▇▇▇▇▇▇▇ ▇▇▇▇▇”) and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated Incorporated. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. This Agreement is effective as of October 3, 2017 (the “Agreement Date”). The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)333‑205234, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formfiling

Introductory. Horizon Pharma, Inc.Kentucky Utilities Company, a Delaware corporation organized under the laws of the Commonwealth of Kentucky and the Commonwealth of Virginia (the “Company”), proposes to issue and sell to sell, and the several underwriters Underwriters named in Schedule A Section 3 hereof (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act for whom you are acting as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with ), propose, severally and not jointly, to purchase, upon the offering terms and sale conditions set forth herein, $300,000,000 aggregate principal amount of the Offered SharesCompany’s First Mortgage Bonds, 4.375% Series due 2045 (the “Bonds”) to be issued under an Indenture, dated as of October 1, 2010 (the “Base Indenture”), between the Company and The Bank of New York Mellon, as trustee thereunder (the “Trustee”), as previously amended and supplemented and as to be further amended and supplemented by Supplemental Indenture No. 7 thereto relating to the Bonds, to be dated as of March 1, 2019 (the “Supplemental Indenture,” and the Base Indenture as so amended and supplemented, the “Indenture”). The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a an automatic shelf registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended223142-01) on Form S-3, including the financial statementsrelated preliminary prospectus or prospectus, exhibits which registration statement became effective upon filing under Rule 462(e) (“Rule 462(e)”) of the rules and schedules thereto, in the form in which it was declared effective by regulations of the Commission (the “Securities Act Regulations”) under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder amended (collectively, the “Securities Act”). Such registration statement covers the registration of the Bonds under the Securities Act. Promptly after the date of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430B (“Rule 430B”) of the Securities Act Regulations and paragraph (b) of Rule 424 (“Rule 424(b)”) of the Securities Act Regulations. Any information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be part of and included in such registration statement pursuant to Rule 430B is referred to as “Rule 430B Information.” Each prospectus used in connection with the offering of the Bonds that omitted Rule 430B Information (other than a “free writing prospectus” as defined in Rule 405 of the Securities Act Regulations (“Rule 405”) that has not been approved in writing by the Company and the Representatives), including any information related prospectus supplement and the documents incorporated by reference therein pursuant to Item 12 of Form S-3, is herein called a “preliminary prospectus.” Such registration statement, at any given time, including the amendments or supplements thereto to such time, the exhibits and any schedules thereto at such time, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act at such time and the documents otherwise deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under or included therein by the Securities ActAct Regulations, is herein called the “Registration Statement.” Any registration statement filed The Registration Statement at the time it originally became effective is herein called the “Original Registration Statement.” The final prospectus in the form first furnished to the Underwriters for use in connection with the offering of the Bonds, including the related prospectus supplement and the documents incorporated by the Company reference therein pursuant to Rule 462(b) Item 12 of Form S-3 under the Securities Act as of the date hereof, is herein called the “Rule 462(b) Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval (“▇▇▇▇▇”) system. All references in this Agreement to financial statements and schedules and other information which is “contained,” and from and after “included” or “stated” in the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” , any preliminary prospectus or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by the Rule 462(b) Securities Act Regulations to be a part of or included in the Registration Statement. The , any preliminary prospectus dated [ ]or the Prospectus, 2011 describing as the Offered Shares case may be; and all references in this Agreement to amendments or supplements to the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and Registration Statement, any other preliminary prospectus that describes or the Offered Shares Prospectus shall be deemed to mean and the offering thereof and is used prior to include the filing of any document under the Prospectus Securities Exchange Act of 1934, as amended (as defined belowthe “Exchange Act”) which is called incorporated by reference in or otherwise deemed by the Securities Act Regulations to be a “preliminary prospectus.” The prospectus, part of or included in the formRegistration Statement, such preliminary prospectus or the Prospectus, as the case may be.

Introductory. Horizon Pharma, Inc.Unilife Corporation, a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 11,000,000 shares of its common stock, par value $0.0001 0.01 per share (the “Shares”). The [ ] 11,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,650,000 Shares as provided in Section 2. The additional [ ] 1,650,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇ LLC (“Jefferies”) and ▇▇▇▇▇ ▇▇▇▇▇▇▇ & Company, Incorporated Co. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMPPiper”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)197122, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formRegistration

Introductory. Horizon PharmaCertain stockholders named in Schedule II hereto (the “Selling Stockholders”) of FCStone Group, Inc., a Delaware corporation (the “Company”), proposes propose, severally and not jointly, to issue and sell to the several underwriters named in Schedule A I (the “Underwriters”) an aggregate of [ ] 1,865,042 shares (the “Shares”) of its common stock, par value $0.0001 per share (the “Shares)Common Stock”) of the Company. The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated BMO Capital Markets Corp. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenBMO”) and JMP Banc of America Securities LLC (“JMPBAS”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The terms Representatives and Underwriters shall mean either the singular or plural as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504144499), which contains including a form of prospectus (the “Basic Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including amended at the financial statements, exhibits and schedules thereto, in the form in which time it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be a part thereof of the registration statement at the time of its effectiveness (“Rule 430 Information”), is referred to herein as the “Registration Statement”; and as used herein, the term “Preliminary Prospectus” means the Basic Prospectus included in such registration statement as supplemented by the Preliminary Prospectus supplement dated July 31, 2007 specifically relating to the Shares (and any amendments thereto), any prospectus filed with the Commission pursuant to Rule 430A 424(a) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term “Prospectus” means the Basic Prospectus as supplemented by the prospectus supplement in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Shares. Any reference in this Agreement to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, is called as of the effective date of the Registration Statement or the date of such Preliminary Prospectus or the Prospectus, as the case may be and any reference to “amend”, “amendment” or “supplement” with respect to the Registration Statement.” Any registration statement , the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed by the Company pursuant to Rule 462(b) after such date under the Securities Exchange Act is called of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Rule 462(bExchange Act”) Registration Statement,” and from and after that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the date and time of filing of meanings given to such terms in the Rule 462(b) Registration Statement and the term “Registration Statement” shall include the Rule 462(b) Registration StatementProspectus. The preliminary prospectus dated [ ], 2011 describing the Offered Shares Company and the offering thereof is called Selling Stockholders hereby confirm their its agreement with the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon Pharma, Inc.Dynavax Technologies Corporation, a Delaware corporation (the “Company”), proposes to issue and sell sell, pursuant to the terms of this Agreement, to the several underwriters named in Schedule A hereto (the “Underwriters,” or, each, an “Underwriter”) ), an aggregate of [ ] 5,000,000 shares of its common stock, $0.001 par value $0.0001 per share (the “SharesCommon Stock”), of the Company. The [ ] Shares aggregate of 5,000,000 shares so proposed to be sold by the Company are called is hereinafter referred to as the “Firm Shares.” In addition, the Stock”. The Company has granted also proposes to sell to the Underwriters an option to purchase Underwriters, upon the terms and conditions set forth in Section 3 hereof, up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called 750,000 shares of Common Stock (the “Optional Shares.” Stock”). The Firm Shares and, if Stock and to the extent such option is exercised, the Optional Shares Stock are hereinafter collectively called referred to as the “Offered SharesStock.” ▇▇▇▇▇▇▇ and Company, LLC, RBC Capital Markets, LLC and ▇▇▇▇▇▇▇ ▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act L.L.C. are acting as the representatives of the several Underwriters (and in such capacity, capacity are hereinafter referred to as the “Representatives.” An “automatic shelf registration statement” as defined in Rule 405 of the rules and regulations (the “Rules and Regulations”) promulgated under the Securities Act of 1933, as amended (the “Securities Act”) on Form S-3 (File No. 333-219781) in connection with the offering and sale respect of the Offered Shares. The Company Stock has prepared and been filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 not earlier than three (File No. 333-168504), which contains a form of prospectus 3) years prior to be used in connection with the public offering and sale of the Offered Shares. Such date hereof; such registration statement, as amended, including the financial statements, exhibits and schedules any post-effective amendment thereto, in became effective on filing; and no stop order suspending the form in which it was declared effective effectiveness of such registration statement or any part thereof has been issued and no proceeding for that purpose has been initiated or threatened by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration StatementCommission,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the form

Introductory. Horizon PharmaPan American Financial, Inc.L.P., a Delaware corporation limited partnership (the “CompanySelling Shareholder”), ) proposes to issue and sell to the several underwriters named in Schedule A (the “List of the Underwriters”) attached hereto (collectively, the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Firm Offered Shares”) of Common Stock, no par value (the “Common Stock”), of United PanAm Financial Corp., a California corporation (the “Company”) in accordance with the terms and conditions of this Underwriting Agreement (the “Agreement”). The [ ] Shares to be sold Each person named in Schedule B attached hereto (collectively, the “Partners” and each, a “Partner”) has previously designated its portion of the shares of Common Stock of the Company held by the Company are called Selling Shareholder, of which PAFGP LLC, a California limited liability company, is the general partner (the “Firm Shares.” General Partner”), for the offer and sale pursuant to this Agreement. In addition, the Company Selling Shareholder, has granted to the Underwriters an option to purchase up to an additional [ ] Shares shares (the “Optional Offered Shares”) of Common Stock, as provided in Section 22 (the “Purchase, Sale, and Delivery of the Offered Shares”). The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Offered Shares and, if and to the extent such option is exercised, the Optional Offered Shares are collectively called the “Offered Shares.” JMP Securities LLC (“JMP”) and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) Inc. have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504182368), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits exhibits, and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein, any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 433 under the Securities Act, or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Such prospectus, 2011 describing in the Offered Shares and form first filed with the offering thereof Commission pursuant to Rule 424(b) under the Securities Act in accordance with Section 5(a) thereunder is called the “Preliminary Prospectus,” and . Each preliminary prospectus, including the Preliminary Prospectus and any other preliminary prospectus that describes subject to completion dated [ ] included in the Offered Shares and the offering thereof and is used registration statement prior to the filing of time such registration statement has become effective (including any supplements thereto) is referred to as a “preliminary prospectus”. All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus, the Prospectus, or an Issuer Free Writing Prospectus (as defined in Section 1 (A) below) ), or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“▇▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is called a “preliminary prospectus.contained,” The prospectus, “included,” or “stated” in the formRegistration Statement or the Prospectus (and all other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Registration Statement or the Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement or the Prospectus shall be deemed to mean and include the filing of any document under the Exchange Act which is or is deemed to be incorporated by reference in the Registration Statement or the Prospectus, as the case may be. The Company, the Selling Shareholder and the General Partner hereby confirm their respective agreements with the Underwriters as follows:

Introductory. Horizon Pharma, Inc.La Jolla Pharmaceutical Company, a Delaware California corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 3,731,344 shares of its common stock, par value $0.0001 per share (the “Shares”). The [ ] 3,731,344 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 559,700 Shares, as provided in Section 2. The additional [ ] 559,700 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇.▇. ▇▇▇▇▇, ▇ Securities LLC (“▇.▇. ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ) and ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. Unless otherwise specified or required by context, the term the “Company” refers to the Company and its subsidiaries on a consolidated basis. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, as amended, File No. 333-168504)214721, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called in connection with the “Rule 462(b) Registration Statement,” offer and from and after the date and time sale of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formcalled

Introductory. Horizon PharmaVeradermics, Inc.Incorporated, a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [●] shares of its common stock, par value $0.0001 0.00001 per share (the “Shares”). The [ [●] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [●] Shares as provided in Section 2. The additional [ [●] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇▇▇▇ LLC (“▇▇▇▇▇▇▇▇▇”), Leerink Partners LLC (“Leerink Partners”), Citigroup Global Markets Inc. (“Citi”) and ▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇▇▇ & Company, Incorporated Co. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP▇▇”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504)292657, which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formany

Introductory. Horizon Pharma, Inc.This Agreement is among Whitestone REIT, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, SunTrust ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company▇▇▇▇, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act Inc., acting as representatives of the several Underwriters representative (in such capacity, if and as applicable, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered several underwriters named in Schedule A hereto (collectively, the “Underwriters,” which term shall also include any underwriter hereinafter substituted as provided in Section 9 hereof), with respect to (i) the sale by the Company and the purchase by the Underwriters, acting severally and not jointly, of 7,000,000 common shares of beneficial interest, par value $0.001 per share of the Company (the “Common Shares”) and (ii) the grant by the Company to the Underwriters, acting severally and not jointly, of the option described in Section 2 hereof to purchase all or any part of 1,050,000 additional Common Shares. The aforesaid 7,000,000 shares of Common Stock (the “Firm Shares”) to be purchased by the Underwriters and all or any part of the 1,050,000 Common Shares subject to the option described in Section 2 hereof (the “Optional Shares”) are herein called, collectively, the “Shares.” The Company understands that the Underwriters propose to make a public offering of the Shares as soon as the Representative deems advisable after this Agreement has been executed and delivered. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 S-3 (File No. 333-168504), which contains a form of prospectus to be used in connection with 203727) covering the public offering and sale of the Offered Shares. Such registration statement, as amendedcertain securities, including the financial statementsShares, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amendedamended (the “Securities Act”), and the rules and regulations promulgated thereunder (collectively, the “Securities ActAct Regulations”), which shelf registration statement was declared effective by the Commission on May 18, 2015. Such registration statement, as of any time, means such registration statement as amended by any post-effective amendments thereto to such time, including the exhibits and any information schedules thereto at such time, the documents incorporated or deemed to be incorporated by reference therein at such time pursuant to Item 12 of Form S-3 under the Securities Act and the documents otherwise deemed to be a part thereof at as of such time pursuant to Rule 430B under the Securities Act Regulations (“Rule 430B”), and is referred to herein as the “Registration Statement;” provided, however, that the “Registration Statement” without reference to a time means such registration statement as amended by any post-effective amendments thereto as of the time of effectiveness the first contract of sale for the Shares, which time shall be considered the “new effective date” of such registration statement with respect to the Shares within the meaning of paragraph (f)(2) of Rule 430B, including the exhibits and schedules thereto as of such time, the documents incorporated or deemed incorporated by reference therein at such time pursuant to Item 12 of Form S-3 under the Securities Act and the documents otherwise deemed to be a part thereof as of such time pursuant to the Rule 430B. Any preliminary prospectuses used in connection with the offering of the Shares, including the documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, are collectively referred to herein as a “preliminary prospectus.” Promptly after execution and delivery of this Agreement, the Company will prepare and file a final prospectus relating to the Shares in accordance with the provisions of Rule 424(b) under the Securities Act Regulations (“Rule 424(b)”). The final prospectus, in the form filed with the Commission pursuant to Rule 430A 424(b) in connection with the offering of the Shares, including the documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, is called referred to herein as the “Prospectus.” For purposes of this Agreement, all references to the Registration Statement.” Any registration statement , any preliminary prospectus, the Prospectus or any amendments or supplements to any of the foregoing shall be deemed to include the copy filed by with the Company Commission pursuant to Rule 462(bits Electronic Data Gathering, Analysis and Retrieval system (or any successor system) under the Securities Act is called the (“Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement▇▇▇▇▇”). The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is As used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formthis Agreement:

Introductory. Horizon Pharma, Global Signal Inc., a Delaware corporation (the “"Company”"), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ ] 5,575,000 shares (the "Firm Common Shares") of its common stockCommon Stock, par value $0.0001 0.01 per share (the “Shares"Common Stock"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 575,000 shares (the "Optional Common Shares") of Common Stock, as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Common Shares and, if and to the extent such option is exercised, the Optional Common Shares are collectively called the “Offered "Common Shares.” ". ▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇▇▇ & CompanyCo. Incorporated, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Banc of America Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “"Representatives”") in connection with the offering and sale of the Offered Common Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 S-11 (File No. 333-168504121576), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Common Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, 1933 and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “"Registration Statement.” ". Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” ", and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The Such prospectus, in the form

Introductory. Horizon Pharma, Inc.PPL Electric Utilities Corporation, a Delaware Pennsylvania corporation (the “Company”), proposes to issue and sell to sell, and the several underwriters Underwriters named in Schedule A Section 3 hereof (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act for whom you are acting as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with ), propose, severally and not jointly, to purchase, upon the offering terms and sale conditions set forth herein, $300,000,000 aggregate principal amount of the Offered SharesCompany’s First Mortgage Bonds, 4.125% Series due 2044 (the “Bonds”) to be issued under an Indenture, dated as of August 1, 2001, between the Company and The Bank of New York Mellon, as trustee thereunder (the “Trustee”), as previously amended and supplemented and as to be further amended and supplemented by Supplemental Indenture No. 16 thereto relating to the Bonds (the “Supplemental Indenture”), to be dated as of June 1, 2014 (such Indenture, as so supplemented, the “Indenture”). The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a an automatic shelf registration statement on Form S-1 (File No. 333-168504), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended180410-03) on Form S-3, including the financial statementsrelated preliminary prospectus or prospectus, exhibits which registration statement became effective upon filing under Rule 462(e) (“Rule 462(e)”) of the rules and schedules thereto, in the form in which it was declared effective by regulations of the Commission (the “Securities Act Regulations”) under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder amended (collectively, the “Securities Act”). Such registration statement covers the registration of the Bonds under the Securities Act. Promptly after the date of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430B (“Rule 430B”) of the Securities Act Regulations and paragraph (b) of Rule 424 (“Rule 424(b)”) of the Securities Act Regulations. Any information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be part of and included in such registration statement pursuant to Rule 430B is referred to as “Rule 430B Information.” Each prospectus used in connection with the offering of the Bonds that omitted Rule 430B Information (other than a “free writing prospectus” as defined in Rule 405 of the Securities Act Regulations that has not been approved in writing by the Company and the Representatives), including any information related prospectus supplement and the documents incorporated by reference therein pursuant to Item 12 of Form S-3, is herein called a “preliminary prospectus.” Such registration statement, at any given time, including the amendments or supplements thereto to such time, the exhibits and any schedules thereto at such time, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act at such time and the documents otherwise deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under or included therein by the Securities ActAct Regulations, is herein called the “Registration Statement.” Any registration statement filed The Registration Statement at the time it originally became effective is herein called the “Original Registration Statement.” The final prospectus in the form first furnished to the Underwriters for use in connection with the offering of the Bonds, including the related prospectus supplement and the documents incorporated by the Company reference therein pursuant to Rule 462(b) Item 12 of Form S-3 under the Securities Act as of the date hereof and any preliminary prospectuses that form a part thereof, is herein called the “Rule 462(b) Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (“E▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is “contained,” and from and after “included” or “stated” in the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” , any preliminary prospectus or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by the Rule 462(b) Securities Act Regulations to be a part of or included in the Registration Statement. The , any preliminary prospectus dated [ ]or the Prospectus, 2011 describing as the Offered Shares case may be; and all references in this Agreement to amendments or supplements to the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and Registration Statement, any other preliminary prospectus that describes or the Offered Shares Prospectus shall be deemed to mean and the offering thereof and is used prior to include the filing of any document under the Prospectus Securities Exchange Act of 1934, as amended (as defined belowthe “Exchange Act”) which is called incorporated by reference in or otherwise deemed by the Securities Act Regulations to be a “preliminary prospectus.” The prospectus, part of or included in the formRegistration Statement, such preliminary prospectus or the Prospectus, as the case may be.

Introductory. Horizon PharmaImago BioSciences, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [•] shares of its common stock, par value $0.0001 [•] per share (the “Shares”). The [ [•] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [•] Shares as provided in Section 2. The additional [ [•] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇▇▇▇ LLC (“Jefferies”), ▇▇▇▇▇ and Company LLC (“Cowen”), ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ ) and CompanyGuggenheim Securities, LLC (“CowenGuggenheim”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 333-[•] which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formit

Introductory. Horizon Pharma, Inc.Gladstone Commercial Corporation, a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (the “Underwriters”) an aggregate of [ ] 1,400,000 shares (the “Shares”) of its common stockCommon Stock, par value $0.0001 0.001 per share (the “SharesCommon Stock”). The [ ] Company is the indirect general partner of Gladstone Commercial Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The 1,400,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 210,000 Shares as provided in Section 2. The additional [ ] 210,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A hereto, the term “Representative” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)190931, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]June 2, 2011 2014 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus supplement to the Base Prospectus in preliminary prospectus form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus), in together with the formBase

Introductory. Horizon Pharma, AmeriVest Properties Inc., a Delaware Maryland corporation (the “"Company”"), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ ] 2,000,000 shares (the "Firm Common Shares") of its common stock, par value $0.0001 .001 per share (the “Shares"Common Stock"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares 300,000 shares (the "Optional Common Shares") of Common Stock, as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Common Shares and, if and to the extent such option is exercised, the Optional Common Shares are collectively called the “Offered "Common Shares.” " ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company▇, LLC Incorporated (“Cowen”"FBW") and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “Representatives”"Representative") in connection with the offering and sale of the Offered Common Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 SB-2 (File No. 333-16850463934), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Common Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act, is called the “"Registration Statement.” " Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “"Rule 462(b) Registration Statement,” " and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “"Registration Statement” " shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The Such prospectus, in the formform first used by the Underwriters to confirm sales of the Common Shares, is called the "Prospectus." All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus or the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System ("▇▇▇▇▇"). The Company hereby confirms its agreements with the Underwriters as follows:

Introductory. Horizon MEI Pharma, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 17,500,000 shares of its common stock, par value $0.0001 0.00000002 per share (the “Shares”). The [ ] 17,500,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 2,625,000 Shares as provided in Section 2. The additional [ ] 2,625,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇▇▇▇ LLC (“Jefferies”), ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ) and ▇▇▇▇▇ and CompanyFargo Securities, LLC (“Cowen”) and JMP Securities LLC (“JMP▇▇▇▇▇ Fargo”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)238056, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formto

Introductory. Horizon Pharma▇▇▇▇▇ Life Sciences, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [●] shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ [●] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [●] Shares as provided in Section 2. The additional [ [●] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated LLC (“StifelJefferies”), ) and ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 333-[●] which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formform first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of

Introductory. Horizon Pharma, Inc.Affimed Therapeutics B.V., a Delaware corporation company incorporated under the laws of the Netherlands (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [—] shares of its common stockshares, par value $0.0001 €0.01 per share (the “Common Shares”). The [ [—] Common Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [—] Common Shares as provided in Section 2. The additional [ [—] Common Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities Leerink Partners LLC (“JMPLeerink”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (F-1, File No. 333-168504), 197097 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Company has prepared and filed, 2011 describing in accordance with Section 12 of the Offered Shares Securities Exchange Act of 1934, as amended, and the offering thereof is called rules and regulations thereunder (collectively, the “Preliminary Prospectus,” and Exchange Act”), a registration statement (as amended, the Preliminary Prospectus and any other preliminary prospectus that describes “Exchange Act Registration Statement”) on Form 8-A (File No. [—]) under the Offered Shares and the offering thereof and is used prior Exchange Act to the filing register, under Section 12(b) of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formExchange Act,

Introductory. Horizon Pharma, Inc.NewLink Genetics Corporation, a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 4,000,000 shares of its common stock, par value $0.0001 0.01 per share (the “Shares”). The [ ] 4,000,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 600,000 Shares as provided in Section 2. The additional [ ] 600,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” Jefferies & Company, Inc. (“Jefferies”) and ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. This Agreement is effective as of January 30, 2013 (the “Agreement Date”). The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)333‑185721, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus supplement dated [ ]January 29, 2011 2013 describing the Offered Shares and the offering thereof (the “Preliminary Prospectus Supplement”), together with the Base Prospectus, is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other prospectus supplement to the Base Prospectus in preliminary prospectus form that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formto

Introductory. Horizon Pharma, Inc.First Potomac Realty Trust, a Delaware corporation Maryland real estate investment trust (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares 4,800,000 of its common stockshares (the “Firm Shares”) of beneficial interest, par value $0.0001 .001 per share (the “Common Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 720,000 Common Shares (the “Option Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇KeyBanc Capital Markets, ▇▇▇▇▇▇▇▇ & Company, Incorporated a division of McDonald Investments Inc. (“StifelKCM”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company is the sole general partner of First Potomac Realty Investment Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-11 (File No. 333-168504115958), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement Statement, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]Such prospectus, 2011 describing in the Offered Shares and form first used by the offering thereof Underwriters to confirm sales of the Shares, is called the “Preliminary Prospectus,.” All references in this Agreement to the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus or the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“E▇▇▇▇”). Each of the Company and the Preliminary Prospectus and any other preliminary prospectus that describes Operating Partnership hereby confirms its agreements with the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (Underwriters as defined below) is called a “preliminary prospectus.” The prospectus, in the formfollows:

Introductory. Horizon Pharma, Inc.Axovant Sciences Ltd., a Delaware corporation company incorporated and organized under the laws of Bermuda (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] shares of its 6,742,179 common stockshares, par value $0.0001 0.00001 per common share (the “Shares”). The [ ] 6,742,179 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,011,326 Shares as provided in Section 2. The additional [ ] 1,011,326 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇.▇. ▇▇▇▇▇▇ Securities LLC (“▇.▇. ▇▇▇▇▇▇”), ▇▇▇▇▇▇ ▇▇▇▇▇▇▇ & Co. LLC (“▇▇▇▇▇▇ ▇▇▇▇▇▇▇”) and ▇▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMPJefferies”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)215387, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formRule

Introductory. Horizon PharmaPPL Energy Supply, Inc.LLC, a limited liability company organized under the laws of the State of Delaware corporation (the “Company”), proposes to issue and sell to sell, and the several underwriters Underwriters named in Schedule A Section 3 hereof (the “Underwriters”) an aggregate of [ ] shares of its common stock, par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act for whom you are acting as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with propose, severally and not jointly, to purchase, upon the offering terms and sale conditions set forth herein, $300,000,000 aggregate principal amount of the Offered SharesCompany’s 6.20% Senior Notes due 2016 (the “Notes”) to be issued under an Indenture, dated as of October 1, 2001, between the Company and JPMorgan Chase Bank, N.A. (formerly The Chase Manhattan Bank), as trustee thereunder (the “Trustee”), as heretofore supplemented and as to be further supplemented by Supplemental Indenture No. 4 thereto relating to the Notes (“Supplemental Indenture No. 4”) (as so supplemented, the “Indenture”). The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a an automatic shelf registration statement on Form S-1 S-3 (File No. 333-168504132574-01), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statementsrelated preliminary prospectus or prospectuses, exhibits which registration statement became effective upon filing under Rule 462(e) (“Rule 462(e)”) of the rules and schedules thereto, in the form in which it was declared effective by regulations of the Commission (the “Securities Act Regulations”) under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder amended (collectively, the “Securities Act”). Such registration statement covers the registration of the Notes under the Securities Act. Promptly after the date of this Agreement, the Company will prepare and file a prospectus in accordance with the provisions of Rule 430B (“Rule 430B”) of the Securities Act Regulations and paragraph (b) of Rule 424 (“Rule 424(b)”) of the Securities Act Regulations. Any information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be part of and included in such registration statement pursuant to Rule 430B is referred to as “Rule 430B Information.” Each prospectus used in connection with the offering of the Notes that omitted Rule 430B Information (other than a “free writing prospectus” as defined in Rule 405 of the Securities Act Regulations that has not been approved in writing by the Company and the Representatives) is herein called a “preliminary prospectus.” Such registration statement, at any given time, including the amendments thereto to such time, the exhibits and any information schedules thereto at such time, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act at such time and the documents otherwise deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under or included therein by the Securities ActAct Regulations, is herein called the “Registration Statement.” Any registration statement filed The Registration Statement at the time it originally became effective is herein called the “Original Registration Statement.” The final prospectus in the form first furnished to the Underwriters for use in connection with the offering of the Notes, including the documents incorporated by the Company reference therein pursuant to Rule 462(b) Item 12 of Form S-3 under the Securities Act as of the date hereof and any preliminary prospectuses that form a part thereof, is herein called the “Rule 462(b) Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (“▇▇▇▇▇”). All references in this Agreement to financial statements and schedules and other information which is “contained,” and from and after “included” or “stated” in the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” , any preliminary prospectus or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by the Rule 462(b) Securities Act Regulations to be a part of or included in the Registration Statement. The , any preliminary prospectus dated [ ]or the Prospectus, 2011 describing as the Offered Shares case may be; and all references in this Agreement to amendments or supplements to the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and Registration Statement, any other preliminary prospectus that describes or the Offered Shares Prospectus shall be deemed to mean and the offering thereof and is used prior to include the filing of any document under the Prospectus Securities Exchange Act of 1934 (as defined belowthe “Exchange Act”) which is called incorporated by reference in or otherwise deemed by the Securities Act Regulations to be a “preliminary prospectus.” The prospectus, part of or included in the formRegistration Statement, such preliminary prospectus or the Prospectus, as the case may be.

Introductory. Horizon PharmaVirgin Galactic Holdings, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A agrees with Credit Suisse Securities (the USA) LLC (“UnderwritersCredit Suisse”) an aggregate of [ ] shares of its common stock), par value $0.0001 per share (the “Shares). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] Shares as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇ ▇▇▇▇▇▇▇ & Company, Incorporated Co. LLC (“Stifel”), ▇▇▇▇▇▇ and Company, LLC (“Cowen▇▇▇▇▇▇▇”) and JMP Securities ▇▇▇▇▇▇▇ ▇▇▇▇▇ & Co. LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacitycollectively with Credit Suisse and ▇▇▇▇▇▇ ▇▇▇▇▇▇▇, the “RepresentativesManagers” and, each individually, a “Manager”) in connection with to sell from time to time to or through a Manager, as sales agent and/or principal, shares (the offering and sale “Shares”) of the Offered SharesCompany’s common stock, $0.0001 par value (“Common Stock”), having an aggregate gross sales price not to exceed $400,000,000 on the terms set forth in this Distribution Agency Agreement. The Company agrees that whenever it determines to sell Shares directly to any Managers as principal, the Company and the applicable Managers will enter into a separate written Terms Agreement (each, a “Terms Agreement”), in substantially the form of Annex I hereto, relating to such sale in accordance with Section 3(k) hereof. References herein to “this Agreement” or to matters contained “herein” or “hereunder,” or words of similar import, mean this Distribution Agency Agreement and any applicable Terms Agreement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”as defined below) a registration statement statement, on Form S-1 S-3 (File No. 333-168504272826), which contains a form of prospectus to be used in connection with covering the public offering and sale of certain securities of the Offered Shares. Such registration statement, as amendedCompany, including the financial statementsShares, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amendedamended (the “1933 Act”), and the rules and regulations promulgated thereunder (collectively, the “Securities Act1933 Act Regulations”), including a related prospectus or prospectuses, which has become effective. The “Registration Statement,” as of any information time, means such registration statement as amended by any post-effective amendments thereto at such time, including the exhibits and any schedules thereto at such time, the documents incorporated or deemed to be incorporated by reference therein at such time and the documents otherwise deemed to be a part thereof at the as of such time of effectiveness pursuant to Rule 430A under 430B of the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities 1933 Act is called the Regulations (“Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term 430B”). The “Registration Statement” without reference to a time means such registration statement as amended by any post-effective amendments thereto as of the time of the first contract of sale for the Shares, which time shall include be considered the “new effective date” of the Registration Statement with respect to the Shares within the meaning of paragraph (f)(2) of Rule 462(b430B (“Rule 430B(f)(2)”), including the exhibits and any schedules thereto at such time, the documents incorporated or deemed to be incorporated by reference therein at such time and the documents otherwise deemed to be a part thereof as of such time pursuant to Rule 430B. Promptly after execution and delivery of this Agreement, the Company will prepare and file a final prospectus supplement relating to the Shares in accordance with the provisions of Rule 424(b) Registration Statementof the 1933 Act Regulations (“Rule 424(b)”). The preliminary prospectus dated [ ]final base prospectus, 2011 describing as amended in the Offered Shares and form in which it has been filed most recently with the offering thereof Commission in accordance with Section 4(b) or 4(c) hereof, including the documents incorporated or deemed incorporated by reference therein, is called referred to herein as the “Preliminary Base Prospectus,.” and Such final prospectus supplement, as amended by the Preliminary prospectus supplement filed most recently with the Commission in accordance with Section 4(b), 4(c) or 4(n) hereof, as the case may be, including the documents incorporated or deemed to be incorporated by reference therein, is referred to herein as the “Prospectus Supplement.” The Base Prospectus, as amended by the Prospectus Supplement and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined belowsupplement(s) is called a “preliminary prospectus.” The prospectusthereto, in the formform the Base Prospectus, the Prospectus Supplement and any such prospectus supplement(s) are first furnished to the applicable Managers for use in connection with the offering and sale of Shares, are collectively referred to herein as the “Prospectus.” For purposes of this Agreement, all references to the Registration Statement, any preliminary prospectus or the Prospectus or any amendment or supplement thereto shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (or any successor system) (“▇▇▇▇▇”). As used in this Agreement:

Introductory. Horizon Pharma, Inc., a Delaware corporation AmeriCredit Corp. (the “"Company”"), proposes to issue and sell to the several underwriters named in Schedule A (the “"Underwriters”") an aggregate of [ ] 8,000,000 shares (the "Firm Shares") of its common stockCommon Stock, par value $0.0001 .01 per share (the “"Common Shares"). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 1,200,000 Common Shares (the "Option Shares"), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Option Shares are collectively called the “Offered "Shares.” ". BancBoston ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”)▇▇▇▇▇▇▇▇ Inc., ▇▇▇▇▇▇▇ ▇▇▇▇▇ ▇▇▇▇▇▇ Inc. and Company, LLC (“Cowen”) and JMP Securities LLC (“JMP”) U.S. Bancorp ▇▇▇▇▇ ▇▇▇▇▇▇▇ Inc. have agreed to act as the representatives of the several Underwriters (in such capacity, the “"Representatives”") in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “"Commission”") a registration statement on Form S-1 S-3 (File No. 333-16850482999), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, 1933 and the rules and regulations promulgated thereunder (collectively, the “"Securities Act”"), including all documents incorporated or to be deemed incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 434 under the Securities Act or the Securities Exchange Act of 1934 and the rules and regulations promulgated thereunder (collectively, the "Exchange Act"), is called the “"Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement". The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formAny

Introductory. Horizon PharmaMinrad International, Inc., a Delaware corporation (the “Company”), ) proposes to issue and sell to the several underwriters named in Schedule A I (the “Underwriters”) an aggregate of [ [10,000,000] shares (the “Firm Shares”) of its common stockCommon Stock, par value $0.0001 0.01 per share (the “SharesCommon Stock”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [1,500,000] Shares shares (the “Optional Shares”), as provided in Section 2. The additional [ ] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & CompanyCo., Incorporated Inc. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenOppenheimer”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The terms Representative and Underwriters shall mean either the singular or plural as the context requires. The Company understands that the Underwriters propose to make a public offering of the Shares as soon as the Representative deems advisable after this Agreement has been executed and delivered. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 SB-2 (File No. 333-168504133506), which contains a form of prospectus to be used in connection with the public offering and sale related preliminary prospectus, or prospectuses, covering the registration of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission Shares under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder amended (collectively, the “Securities Act”). Promptly after execution and delivery of this Agreement, including any information deemed to be the Company will prepare and file a part thereof at prospectus in accordance with the time provisions of effectiveness pursuant to Rule 430A under (“Rule 430A”) of the Securities Act, is called rules and regulations of the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) Commission under the Securities Act is called (the “Securities Act Regulations”) and paragraph (b) of Rule 462(b424 (“Rule 424(b)”) Registration Statement,” and from and after the date and time of filing of the Securities Act Regulations. The information included in such prospectus that was omitted from such registration statement at the time it became effective but that is deemed to be part of such registration statement at the time it became effective pursuant to paragraph (b) of Rule 462(b) Registration Statement the term 430A is referred to as “Registration StatementRule 430A Information.” shall include Each prospectus that omitted the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ]430A Information, 2011 describing the Offered Shares that was used after such effectiveness and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing execution and delivery of the Prospectus (as defined below) this Agreement is herein called a “preliminary prospectus.” The prospectusSuch registration statement, in including the formexhibits, financial statements and any schedules thereto, at the time it became effective, and including the Rule 430A Information, is

Introductory. Horizon PharmaFive Prime Therapeutics, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 3,410,000 shares of its common stock, par value $0.0001 0.001 per share (the “Shares”). The [ ] 3,410,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ ] 511,500 Shares as provided in Section 2. The additional [ ] 511,500 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇Citigroup Global Markets Inc., ▇▇▇Leerink Partners LLC and ▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇▇▇▇▇ and CompanyFargo Securities, LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. Citigroup Global Markets Inc. and Leerink Partners LLC shall be referred to herein as the “Lead Representatives.” The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-3, File No. 333-168504)200067, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A or Rule 430B under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formsuch

Introductory. Horizon Pharma, ▇▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇ Group Inc., a Delaware Texas corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ ] 5,000,000 shares (the “Firm Shares”) of its the Company’s common stock, par value $0.0001 0.01 per share (the “Shares”). The [ ] Shares to be sold by the Company are called the “Firm Shares.” In addition, the shareholders of the Company has named in Schedule B (collectively, the “Selling Shareholders”) have severally granted to the Underwriters an option to purchase up to an additional [ ] 750,000 Shares (the “Optional Shares”), as provided in Section 2. The additional [ ] Shares , with each Selling Shareholder selling up to be sold by the Company pursuant to amount set forth opposite such option are collectively called the “Optional Shares.” Selling Shareholder’s name in Schedule B. The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated Inc. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“CowenJefferies”) and JMP Securities LLC (“JMP”) have has agreed to act as representatives representative of the several Underwriters (in such capacity, the “RepresentativesRepresentative”) in connection with the offering and sale of the Offered Shares. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 S-3 (File No. 333-168504134448), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, and, in the event any post-effective amendment thereto becomes effective prior to the First Closing Date (as defined herein) or any applicable Option Closing Date (as defined herein), including such registration statement as so amended, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formthe

Introductory. Horizon Pharma, Inc.Gladstone Commercial Corporation, a Delaware Maryland corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A hereto (the “Underwriters”) an aggregate of [ ] 2,400,000 shares (the “Shares”) of its common stock6.625% Series E Cumulative Redeemable Preferred Stock, par value $0.0001 0.001 per share (the “SharesPreferred Stock”). The [ ] Company is the indirect general partner of Gladstone Commercial Limited Partnership (the “Operating Partnership”), a Delaware limited partnership that serves as the Company’s primary operating partnership subsidiary. The 2,400,000 Shares to be sold by the Company are called the “Firm Shares.” In addition, the Company has granted agreed to sell to the Underwriters an option Underwriters, subject to purchase the terms and conditions stated herein, up to an additional [ ] Shares as provided in Section 2360,000 Shares. The additional [ ] 360,000 Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇▇▇▇▇▇ & Company, Incorporated (“Stifel”), ▇. ▇▇▇▇▇ FBR, Inc., ▇.▇. ▇▇▇▇▇▇▇▇ & Co. and Company, ▇▇▇▇▇▇ ▇▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇ LLC (“Cowen”) and JMP Securities LLC (“JMP”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A hereto, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-1 (S-3, File No. 333-168504)229209, which contains including a form of base prospectus (the “Base Prospectus”) to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including all documents incorporated or deemed to be incorporated by reference therein and any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The preliminary prospectus dated [ ], 2011 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the format

Introductory. Horizon Pharma▇▇▇▇▇▇▇ Bio Innovations, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”) an aggregate of [ [—] shares of its common stock, par value $0.0001 0.00001 per share (the “Shares)”) and the stockholders of the Company named in Schedule B (collectively, the “Selling Stockholders”) severally propose to sell to the Underwriters an aggregate of [—] shares. The [ [—] Shares to be sold by the Company and the [—] Shares to be sold by the Selling Stockholders are collectively called the “Firm Shares.” In addition, the Company has granted to the Underwriters an option to purchase up to an additional [ [—] Shares as provided in Section 2. The additional [ [—] Shares to be sold by the Company pursuant to such option are collectively called the “Optional Shares.” The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the “Offered Shares.” ▇▇▇▇▇▇, ▇▇▇ LLC (“Jefferies”) and ▇▇▇▇▇ ▇▇▇▇▇▇▇ & Company, Incorporated Co. (“Stifel”), ▇▇▇▇▇ and Company, LLC (“Cowen”) and JMP Securities LLC (“JMPPiper”) have agreed to act as representatives of the several Underwriters (in such capacity, the “Representatives”) in connection with the offering and sale of the Offered Shares. To the extent there are no additional underwriters listed on Schedule A, the term “Representatives” as used herein shall mean you, as Underwriters, and the term “Underwriters” shall mean either the singular or the plural, as the context requires. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-1 (S-1, File No. 333-168504), 196058 which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules and any documents incorporated by reference thereto, in the form in which it was declared became effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act in connection with the offer and sale of the Offered Shares is called the “Rule 462(b) Registration Statement,” and from and after the date and time of filing of the any such Rule 462(b) Registration Statement the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act, and any documents incorporated by reference thereto, is called the “Prospectus.” The preliminary prospectus dated [ [—], 2011 2014 describing the Offered Shares and the offering thereof is called the “Preliminary Prospectus,” and the Preliminary Prospectus and any other preliminary prospectus that describes the Offered Shares and the offering thereof and is used prior to the filing of the Prospectus (as defined below) is called a “preliminary prospectus.” The prospectus, in the formdocuments