PRINCETON, NEW JERSEY 08542

Exhibit 10.28

CDC IV, LLC

00 XXXXXXX XXXXXX, XXXXX 000

XXXXXXXXX, XXX XXXXXX 00000

September 5, 2007

BioDelivery Sciences International, Inc.

Arius Pharmaceuticals, Inc. and

Arius Two, Inc.

0000 Xxxxxx Xxxxxx Xxxxxxx, Xxxxx 000

Xxxxxxxxxxx, Xxxxx Xxxxxxxx 00000

Attn: Xxxx X. Xxxxx, President and Chief Executive Officer

RE: Clinical Development and License Agreement

Dear Xx. Xxxxx:

The purpose of this letter (this “Letter Agreement”) is to set out certain understandings and agreements between (i) CDC IV, LLC (“CDC”) and (ii) BioDelivery Sciences International, Inc. (“BioDelivery”), Arius Pharmaceuticals, Inc., a wholly-owned subsidiary of BDSI (“Arius”) and Arius Two, Inc., a wholly-owned subsidiary of BioDelivery (“Arius Two”).

Reference is hereby made to that certain Clinical Development and License Agreement (as amended, the “CDC License”), dated as of July 14, 2005 among CDC (as successor in interest to Clinical Development Capital LLC), BioDelivery and Arius. Pursuant to the terms of the CDC License, BioDelivery, Arius and Arius Two have requested that CDC consent to, among other things, (i) the acquisition by Arius Two of certain assets related to the BEMA Fentanyl product from QLT USA, Inc., and (ii) the amendment of the CDC License in connection with such acquisition and the subsequent license of certain rights with respect to such assets by Arius to Meda AB; in each case pursuant to the terms of (A) that certain Sublicensing Consent and Amendment, entered into as of the date hereof, by BDSI, Arius and CDC (the “Sublicensing Consent”) and (B) that certain BEMA Acquisition Consent, Amendment and Waiver, entered into as of the date hereof, by BDSI, Arius, Arius Two and CDC (the “Acquisition Consent” and together with the Sublicensing Consent, collectively, the “CDC Consents”). As a condition to CDC entering into the CDC Consents, CDC is requiring BDSI, Arius and Arius Two to enter into this Letter Agreement. Capitalized terms used herein, but not otherwise defined herein, shall have the meanings set forth in the Acquisition Consent.

1. Defaults and Terminations under the New License. Notwithstanding anything to the contrary set forth in the CDC License, the QLT License, the New License, the Acquisition Agreements, the CDC Consents or any agreements entered into by any of BDSI, Arius or Arius Two in connection with any of the foregoing, BDSI, Arius and Arius Two hereby agree and acknowledge that (i) in no event shall Arius Two declare any default against Arius under the New License, or otherwise exercise any right to terminate the New License or other remedy thereunder, without the written consent of CDC, in its sole and absolute discretion and (ii) in no

event shall CDC be required to cure any defaults by Arius under the New License in order to exercise its rights under Sections 2.04(d) or 14.06 or other similar provisions of the New License. The foregoing restrictions shall terminate to the extent Arius Two fails to satisfy its Obligations (as such term is defined in the certain Security Agreement by and between Arius Two and QLT, dated as of the date hereof (the “QLT Security Agreement”)), QLT thereafter exercises its rights with respect to the Collateral (as defined in the QLT Security Agreement) pursuant to the Acquisition Agreements, and Arius Two’s rights and obligations under the New License are assigned to an Arius Two Assignee.

2. Transfer of Acquired Assets to Arius and Termination of New License. BDSI, Arius and Arius Two hereby agree and acknowledge that upon the termination of the security interest created in favor of QLT under the Acquisition Agreements (i) the New License shall automatically terminate and (ii) simultaneously therewith, Arius Two shall assign and transfer all of its right, title and interest in and to the Acquired Assets to Arius and to the extent any such Acquired Assets are not already subject to a security interest in favor of CDC pursuant to the Security Agreement, such Acquired Assets shall automatically, and without the need for further action on the part of any person or entity, become subject to the security interests (and other provisions) in favor of CDC under the Security Agreement. The parties hereto hereby agree that, notwithstanding anything to the contrary, paragraph 2 of that similar letter between the parties, dated August 2, 2006, concerning the prior acquisition of certain BEMA-related assets by Arius Two from QLT (the “Previous Letter”) shall not apply with respect to the termination of security interests established under the Acquisition Agreements (as defined in the Previous Letter, and not under this letter agreement) with respect to assets concerning Canada and Mexico, which termination is occurring in conjunction with the simultaneous amendment, effective as of the date hereof, of the Acquisition Agreements (as defined herein) to subject such assets to the security interests in favor of QLT established thereunder.

3. Arius Two as a Party to the CDC License Agreement. Each of BDSI, Arius, Arius Two and CDC hereby agree and acknowledge that by executing this Letter Agreement, Arius Two shall, subject to the terms of the Acquisition Agreements, become a party to the CDC License and included as part of the definition of the “Company”, together with BDSI and Arius. From and after the date hereof, Arius Two hereby agrees and acknowledges that, subject to the terms of the Acquisition Agreements, it (i) shall, in addition to BDSI and Arius, be responsible for all of duties and obligations of the “Company” under the CDC License and (ii) shall otherwise be bound by the terms of the CDC License as part of the “Company”. For purposes of clarity, it is hereby agreed and acknowledged that the New License and the Acquisition Agreements (and all documents entered into in connection therewith) shall be considered “Company Agreements” under the CDC License, provided that, upon assignment of Arius Two’s rights and obligations under the New License to any Arius Two Assignee, the New License shall no longer be deemed a “Company Agreement” with respect to Arius Two, but shall still be considered a “Company Agreement” with respect to Arius under the CDC License.

4. Payment of CDC Costs and Expenses. BDSI hereby agrees to reimburse CDC fifty percent (50%) of any and all reasonable, documented legal fees and expenses related to CDC’s review, negotiation and execution of the CDC Consents and all documents and transactions related thereto, including, but not limited to, those documents related to the Royalty Acquisition and Amendment Agreement (and all precursors thereto), such legal fees and expenses not to

exceed $75,000. Such amounts shall be paid by BDSI to CDC by wire transfer of immediately available funds to an account designated by CDC no later than three (3) business days following the HSR Date (as defined in the License and Development Agreement dated as of the date hereof between Meda AB and BDSI); provided, CDC provides to BDSI a detailed xxxx itemizing such expenses.

5. Further Assurances. Upon the request of CDC, each of BDSI, Arius and Arius Two hereby agree to execute and deliver any and all additional instruments and documents and take such other future actions as may be necessary or reasonably requested by CDC to document and consummate the agreements and understandings described in, or otherwise in connection with, this Letter Agreement.

6. Miscellaneous Provisions. This Letter Agreement will be governed by and interpreted in accordance with the internal laws of the State of New York, without regard to its conflicts of laws rules. To the extent that the CDC License or New License (or any other agreements entered into by CDC and one or more of BDSI, Arius or Arius Two in connection therewith) are varied by this Letter Agreement, such variations shall be deemed to be lawfully made amendments to such agreements and to the extent there is a conflict between this Letter Agreement and such other agreements, the terms of this Letter Agreement shall control. Except as modified by this Letter Agreement, the CDC License and the New License (and any other agreements entered into by CDC and one or more of BDSI, Arius or Arius Two in connection therewith), such other agreements shall remain unchanged and in full force and effect. This Letter Agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns. The rights and obligations of each party to this Letter Agreement may not be assigned or delegated by BDSI, Arius or Arius Two without the prior written consent of CDC. This Letter Agreement may be executed in two or more counterparts, each of which will be deemed an original, but all of which taken together will constitute one and the same document. For the purposes hereof, a facsimile copy of this Letter Agreement, including the signature pages hereto, will be deemed an original.

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Please indicate your agreement to the provisions of this Letter Agreement by having a duly authorized officer of each of BDSI, Arius and Arius Two execute this Letter Agreement and then return an executed copy to my attention at the address provided above.

Very truly yours,
CDC IV, LLC
By:		/s/ Xxxxx Xxxxxx
Name:		Xxxxx Xxxxxx
Title:		Partner

AGREED TO AND ACCEPTED AS
OF THE DATE FIRST SET FORTH ABOVE.
ARIUS PHARMACEUTICALS, INC.
By:		/s/ Xxxx X. Xxxxx
Name:		Xxxx X. Xxxxx
Title:		President and CEO

BIODELIVERY SCIENCES INTERNATIONAL, INC.
By:		/s/ Xxxx X. Xxxxx
Name:		Xxxx X. Xxxxx
Title:		President and CEO

ARIUS TWO, INC.
By:		/s/ Xxxx X. Xxxxx
Name:		Xxxx X. Xxxxx
Title:		President and CEO