Securities Purchase Agreement

Contract

                                                                    EXHIBIT 10.1



                         SECURITIES PURCHASE AGREEMENT

      This SECURITIES PURCHASE AGREEMENT (this "Agreement") is dated as of the
9th day of August, 2002, by and between Corixa Corporation, a Delaware
corporation with its principal office at 1124 Columbia Street, Suite 200,
Seattle, WA 98104 (the "Company"), and the several purchasers identified in the
attached Exhibit A (individually, a "Purchaser" and collectively, the
"Purchasers").

      WHEREAS, the Company desires to issue and sell to the Purchasers an
aggregate of (i) approximately 7,322,562 shares (the "Shares") of the authorized
but unissued shares of common stock, $.001 par value per share, of the Company
(the "Common Stock") and (ii) warrants in the form attached as Exhibit B to
purchase an aggregate of approximately 1,244,836 shares of Common Stock (each, a
"Warrant," and collectively, the "Warrants"); and

      WHEREAS, the Purchasers, severally, wish to purchase the Shares and the
Warrants on the terms and subject to the conditions set forth in this Agreement.

      NOW THEREFORE, in consideration of the mutual agreements, representations,
warranties and covenants herein contained, the parties hereto agree as follows:

      1. Definitions. As used in this Agreement, the following terms shall have
the following respective meanings:

            (a) "Affiliate" of a party means any corporation or other business
entity controlled by, controlling or under common control with such party. For
this purpose "control" shall mean direct or indirect beneficial ownership of
fifty percent (50%) or more of the voting or income interest in such corporation
or other business entity.

            (b) "Closing Date" means the date of the Closing (as defined below).

            (c) "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and all of the rules and regulations promulgated thereunder.

            (d) "Majority Purchasers" shall mean Purchasers which, at any given
time, hold greater than two-thirds of the voting power of the Shares purchased
hereunder which are then held by the Purchasers.

            (e) "Material Adverse Effect" shall mean a material adverse change
in the assets, liabilities (contingent or other), affairs, operations or
financial condition of the Company.

            (f) "Operative Agreements" shall mean the Registration Rights
Agreement and the Warrant, together with this Agreement.

            (g) "Registration Rights Agreement" shall mean that certain
Registration Rights Agreement, dated as of the date hereof, between the Company
and the Purchasers.




            (h) "SEC" shall mean the Securities and Exchange Commission.

            (i) "Securities" shall mean the Shares, the Warrants and the
Underlying Shares.

            (j) "Securities Act" shall mean the Securities Act of 1933, as
amended, and all of the rules and regulations promulgated thereunder.

            (k) "Underlying Shares" shall mean the shares of Common Stock
issuable upon exercise of the Warrants.

      2. Purchase and Sale of Securities.

            2.1 Purchase and Sale. Subject to and upon the terms and conditions
set forth in this Agreement, the Company agrees to issue and sell to each
Purchaser, and each Purchaser, severally and not jointly, hereby agrees to
purchase from the Company, at the Closing, the number of Shares set forth
opposite the name of such Purchaser under the heading "Number of Shares To Be
Purchased" on Exhibit A hereto, at a purchase price of $6.13 per share, and a
Warrant to purchase 0.17 shares of Common Stock for every one Share purchased by
the Purchaser at a purchase price per Underlying Share of $.125 and having an
exercise price of $6.13 per underlying share. The total purchase price payable
by each Purchaser for the Securities that such Purchaser is hereby agreeing to
purchase is set forth opposite the name of such Purchaser under the heading
"Aggregate Purchase Price" on Exhibit A hereto. The aggregate purchase price
payable by the Purchasers to the Company for all of the Securities purchased at
the Closing shall be approximately $45,000,000.

            2.2 Closing. The purchase and sale of the Securities to be sold
pursuant to this Agreement shall take place at the offices of Orrick, Herrington
& Sutcliffe LLP, counsel to the Company, at 719 Second Avenue, Suite 900,
Seattle, Washington 98104, at 10:00 a.m., on August 14, 2002, or at such other
time and place as the Company and the Majority Purchasers agree upon orally or
in writing (which time and place are designated as the "Closing"). At the
Closing, the Company shall deliver to each Purchaser a single stock certificate
and a single Warrant representing the number of Securities purchased by such
Purchaser, each to be registered in the name of such Purchaser, or in such
nominee's or nominees' name(s) as designated by such Purchaser in writing in the
form of the Purchaser Questionnaire attached hereto as Appendix I, against
payment of the purchase price therefor by wire transfer of immediately available
funds to such account or accounts as the Company shall designate in writing.

      3. Representations and Warranties of the Company. Except as otherwise
described in the SEC Documents (as defined below), the Company's press releases
since March 31, 2002 (including the documents incorporated by reference therein)
and the disclosure memorandum delivered by the Company to the Investors
concurrent with the execution hereof (the "Disclosure Memorandum"), the Company
hereby represents and warrants to each of the Purchasers as follows:

            3.1 Incorporation. The Company is a corporation duly organized,
validly existing and in good standing under the laws of the state of Delaware
and is qualified to do



                                       2


business and in good standing (with respect to jurisdictions that recognize such
concept) in each jurisdiction in which the character of its properties or the
nature of its business requires such qualification, except where the failure to
so qualify or be in good standing would not have a Material Adverse Effect. The
Company does not have any subsidiaries. Except for short-term investments, the
Company does not own any shares of stock or any other equity or long-term debt
securities of any corporation or have any equity interest in any firm,
partnership, limited liability company, joint venture, association or other
entity. Complete and correct copies of the Company's Amended and Restated
Certificate of Incorporation (the "Restated Certificate") and its Bylaws (the
"Bylaws") as in effect on the date hereof have been filed by the Company with
the SEC. The Company has all requisite corporate power and authority to carry on
its business as now conducted.

            3.2 Capitalization. The authorized capital stock of the Company
consists of (i) 100,000,000 shares of Common Stock, of which 41,781,836 shares
were outstanding as of June 30, 2002 and (ii) 10,000,000 shares of preferred
stock, of which 12,500 shares of Series A Preferred Stock and 37,500 of Series B
Preferred Stock were outstanding as of June 30, 2002. The Company has not issued
any capital stock since June 30, 2002 other than pursuant to employee benefit
plans disclosed in the SEC Documents. The outstanding shares of capital stock of
the Company have been duly and validly issued and are fully paid and
nonassessable, have been issued in compliance with all federal and state
securities laws, and were not issued in violation of any preemptive rights or
similar rights to subscribe for or purchase securities. There are no existing
options, warrants, calls, preemptive (or similar) rights, subscriptions or other
rights, agreements, arrangements or commitments of any character obligating the
Company to issue, transfer or sell, or cause to be issued, transferred or sold,
any shares of the capital stock of the Company or other equity interests in the
Company or any securities convertible into or exchangeable for such shares of
capital stock or other equity interests, and there are no outstanding
contractual obligations of the Company to repurchase, redeem or otherwise
acquire any shares of its capital stock or other equity interests. There are no
voting agreements or other similar agreements with respect to the Common Stock
to which the Company is a party.

            3.3 Authorization. All corporate action on the part of the Company,
its officers, directors and stockholders necessary for the authorization,
execution, delivery and performance of the Operative Agreements and the
consummation of the transactions contemplated therein has been taken. When
executed and delivered by the Company, each of the Operative Agreements shall
constitute the legal, valid and binding obligation of the Company, enforceable
against the Company in accordance with its terms, except as such may be limited
by bankruptcy, insolvency, reorganization or other laws affecting creditors'
rights generally and by general equitable principles. The Company has all
requisite corporate power to enter into the Operative Agreements and to carry
out and perform its obligations under the terms of the Operative Agreements.

            3.4 Valid Issuance of the Securities. The Securities being purchased
by the Purchasers hereunder will, upon issuance pursuant to the terms hereof, be
duly authorized and validly issued, and the Shares will, upon issuance pursuant
to the terms hereof, be fully paid and nonassessable. The Underlying Shares have
been duly and validly authorized and reserved for issuance and, upon exercise of
the Warrants in accordance with their terms, including payment of the exercise
price therefore, the Underlying Shares will be validly issued, fully paid and



                                       3


nonassessable. No preemptive rights, co-sale rights, rights of first refusal or
other similar rights to subscribe for or to purchase the Company's capital stock
exist with respect to the issuance and sale of the Securities by the Company
pursuant to this Agreement and the terms of the Warrants. No stockholder of the
Company has any right (which has not been waived or has not expired by reason of
lapse of time) to require the Company to register the sale of any shares owned
by such stockholder under the Securities Act in the registration statement to be
filed by the Company pursuant to the Registration Rights Agreement (the
"Registration Statement").

            3.5 Financial Statements. The Company has made available (including
via EDGAR) to each Purchaser its audited Statements of Income, Stockholders'
Equity and Cash Flows for the fiscal year ended December 31, 2001, its audited
Balance Sheet as of December 31, 2001, its unaudited Statements of Income,
Stockholders' Equity and Cash Flows for the period from January 1, 2002 through
March 31, 2002 and its unaudited Balance Sheet as of March 31, 2002. All such
financial statements are hereinafter referred to collectively as the "Financial
Statements." The Financial Statements have been prepared in accordance with
generally accepted accounting principles applied on a consistent basis during
the periods involved, and fairly present the financial position of the Company
and the results of its operations as of the date and for the periods indicated
thereon, except that the unaudited financial statements may not be in accordance
with generally accepted accounting principles because of the absence of
footnotes normally contained therein and are subject to normal year-end audit
adjustments which, individually, and in the aggregate, will not be material. The
Company has implemented and maintains a system of internal accounting controls
meeting the SEC requirements, including without limitation the requirements of
Section 13(b)(2) of the Exchange Act. Since March 31, 2002, there has been no
Material Adverse Effect.

            3.6 SEC Documents. The Company has made available (including via
EDGAR) to each Purchaser, a true and complete copy of the Company's Annual
Report on Form 10-K for the fiscal year ended December 31, 2001 (as amended by
the Form 10-K/A filed on June 24, 2002), the Company's Quarterly Report on Form
10-Q for the three months ended March 31, 2002, the Company's Definitive Proxy
Statement for the Annual Meeting held on May 31, 2002 and the Company's Current
Reports on Form 8-K filed after December 31, 2001 and before the date hereof.
The Company will, promptly upon the filing thereof, also furnish to each
Purchaser all statements, reports (including, without limitation, Quarterly
Reports on Form 10-Q and Current Reports on Form 8-K) and definitive proxy
statements filed by the Company with the SEC during the period commencing on the
date hereof and ending on the Closing Date (all such materials required to be
furnished to each Purchaser pursuant to this sentence or pursuant to the next
preceding sentence of this Section 3.6 being called, collectively, the "SEC
Documents"). The Company has filed in a timely manner all documents that the
Company was required to file under the Exchange Act during the 12 months
preceding the date of this Agreement. As of their respective filing dates, the
SEC Documents complied in all material respects with the requirements of the
Exchange Act, and none of the SEC Documents, as of their respective filing
dates, contained any untrue statement of a material fact or omitted to state a
material fact required to be stated therein or necessary in order to make the
statements made therein, in light of the circumstances under which they were
made, not misleading, except to the extent corrected by a subsequently filed SEC
Document.



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            3.7 Consents. All consents, approvals, orders and authorizations
required on the part of the Company in connection with the execution, delivery
or performance of the Operative Agreements and the consummation of the
transactions contemplated therein have been obtained and will be effective as of
the Closing Date.

            3.8 No Conflict. The execution and delivery of the Operative
Agreements by the Company and the consummation of the transactions contemplated
thereby will not conflict with or result in any violation of or default (with or
without notice or lapse of time, or both) under, or give rise to a right of
termination, cancellation or acceleration of any obligation or to a loss of a
material benefit under (i) any provision of the Restated Certificate or Bylaws,
(ii) any material bond, debenture, note or other evidence of indebtedness, or
any material lease, contract, indenture, mortgage, deed of trust, loan
agreement, joint venture or other agreement or instrument to which the Company
is a party or by which it or its property is bound or (iii) except as would not
have a Material Adverse Effect, any judgment, order, statute, law, ordinance,
rule or regulation applicable to the Company or its properties or assets.

            3.9 Brokers or Finders. Except for Pacific Growth Equities, Inc.
(the "Placement Agent"), the Company has not dealt with any broker or finder in
connection with the transactions contemplated by this Agreement, and, except for
certain fees and expenses payable by the Company to the Placement Agent, the
Company has not incurred, and shall not incur, directly or indirectly, any
liability for any brokerage or finders' fees or agents commissions or any
similar charges in connection with this Agreement or any transaction
contemplated hereby.

            3.10 Nasdaq National Market. The Common Stock is registered pursuant
to Section 12(g) of the Exchange Act and is listed on the Nasdaq National Market
System ("Nasdaq"). The Company has taken no action designed to delist, or which,
to the Company's knowledge, is likely to have the effect of, terminating the
registration of the Common Stock under the Exchange Act or delisting the Common
Stock from Nasdaq. The Company shall comply with all requirements of the
National Association of Securities Dealers, Inc. with respect to the issuance of
the Securities and the listing of the Shares and the Underlying Shares on
Nasdaq.

            3.11 Absence of Litigation or Proceeding. There is no action, suit
or proceeding or, to the Company's knowledge, any investigation, pending, or to
the Company's knowledge, threatened by or before any court, governmental body or
regulatory agency against the Company that is required to be disclosed in the
SEC Documents and is not so disclosed. The Company has not received any written
or oral notification of, or request for information in connection with, any
formal or informal inquiry, investigation or proceeding from the SEC or the
National Association of Securities Dealers.

            3.12 Intellectual Property.

                  (a) To the knowledge of the Company, the Company has ownership
or license or legal right to use all patent, copyright, trade secret, trademark,
customer lists, designs, manufacturing or other processes, computer software,
systems, data compilation, research results or other proprietary rights used in
the business of the Company and material to the Company



                                       5


(collectively, "Intellectual Property"), other than Intellectual Property
generally available on commercial terms from other sources.

                  (b) There is no material default by the Company under any
material licenses or other material agreements under which (i) the Company is
granted rights in Intellectual Property or (ii) the Company has granted rights
to others in Intellectual Property owned or licensed by the Company.

                  (c) The Company believes it has taken those steps required in
accordance with sound business practice and commercially reasonable business
judgment to establish and preserve its ownership of all material patent,
copyright, trade secret and other proprietary rights with respect to its
products and technology.

                  (d) To the knowledge of the Company, the present business,
activities and products of the Company do not infringe any intellectual property
of any other person, except where such infringement would not have a Material
Adverse Effect. The Company has not been notified that any proceeding charging
the Company with infringement of any adversely held Intellectual Property has
been filed. To the Company's knowledge, there exists no patent or patent
application held by any other person which includes claims that would be
infringed by the Company in the conduct of its business as currently conducted
and as proposed to be conducted in the SEC Documents, where such infringement
would have a Material Adverse Effect on the Company. To the knowledge of the
Company, the Company is not making unauthorized use of any confidential
information or trade secrets of any person. Neither the Company nor, to the
knowledge of the Company, any of its employees have any agreements or
arrangements with any persons other than the Company restricting the Company's
or any such employee's engagement in business activities that are material
aspects of the Company's business as currently conducted or as proposed to be
conducted in the SEC Documents.

            3.13 Offering Materials. Other than the SEC Documents, the
Disclosure Memorandum and the Operative Agreements (collectively, the "Offering
Materials"), the Company has not distributed and will not distribute prior to
the Closing Date any offering material in connection with the offering and sale
of the Securities. The Company has not in the past nor will it hereafter take
any action to sell, offer for sale or solicit offers to buy any securities of
the Company which would require the offer, issuance or sale of the Securities,
as contemplated by this Agreement, to be registered under Section 5 of the
Securities Act.

            3.14 Investment Company. The Company is not an "investment company"
or an "affiliated person" of, or "promoter" or "principal underwriter" for an
investment company, within the meaning of the Investment Company Act of 1940, as
amended.

            3.15 No Manipulation of Stock. The Company has not taken and will
not, in violation of applicable law, take, any action designed to or that might
reasonably be expected to cause or result in unlawful manipulation of the price
of the Common Stock.

            3.16 No Violations. The Company is not in violation of its Restated
Certificate, Bylaws or other organizational documents, or in violation of any
law, administrative regulation, ordinance or order of any court or governmental
agency, arbitration panel or authority



                                       6


applicable to the Company, which violation, individually or in the aggregate,
would be reasonably expected to have a Material Adverse Effect, or is not in
default (and there exists no condition which, with the passage of time or
otherwise, would constitute a default) in the performance of any material bond,
debenture, note or any other evidence of indebtedness in any indenture,
mortgage, deed of trust or any other material agreement or instrument to which
the Company is a party or by which the Company is bound or by which the property
of the Company is bound, which would be reasonably expected to have a Material
Adverse Effect.

      4. Representations and Warranties of the Purchasers. Each Purchaser
severally for itself, and not jointly with the other Purchasers, represents and
warrants to, and covenants with, the Company as follows:

            4.1 Authorization. All action on the part of such Purchaser and, if
applicable, its officers, directors and stockholders necessary for the
authorization, execution, delivery and performance of the Operative Agreements
and the consummation of the transactions contemplated therein has been taken.
When executed and delivered by such Purchaser, each of the Operative Agreements
will constitute the legal, valid and binding obligation of such Purchaser,
enforceable against such Purchaser in accordance with its terms, except as such
may be limited by bankruptcy, insolvency, reorganization or other laws affecting
creditors' rights generally and by general equitable principles. Such Purchaser
has all requisite power to enter into each of the Operative Agreements and to
carry out and perform its obligations under the terms of the Operative
Agreements.

            4.2 Information. Such Purchaser has received, reviewed and
considered all information it deems necessary in making an informed decision to
make an investment in the Securities; provided that nothing in this sentence
shall lessen or obviate the representations and warranties set forth in Section
3 hereof. Such Purchaser has, in connection with its decision to purchase the
Securities, relied solely upon the SEC Documents and the representations and
warranties of the Company contained in Section 3 of this Agreement (as qualified
by the Disclosure Memorandum).

            4.3 Purchase Entirely for Own Account. Such Purchaser is acquiring
the Securities being purchased by it hereunder for investment, for its own
account, and not for resale or with a view to distribution thereof in violation
of the Securities Act.

            4.4 Investor Status. Such Purchaser has the knowledge and experience
in financial and business matters as to be capable of evaluating the merits and
risks of an investment in the Securities. Such Purchaser certifies and
represents to the Company that it is an "Accredited Investor" as defined in Rule
501 of Regulation D promulgated under the Securities Act and was not organized
for the purpose of acquiring the Securities. Such Purchaser's financial
condition is such that it is able to bear the risk of holding the Securities for
an indefinite period of time and the risk of loss of its entire investment.

            4.5 Confidential Information. Such Purchaser understands that,
except for the SEC Documents, any information provided to such Purchaser by the
Company in connection with the offering contemplated by this Agreement,
including, without limitation, the existence and nature of discussions regarding
this offering, the Operative Agreements and any other



                                       7


presentations or nonpublic information given by the Company to Purchaser
(collectively, the "Nonpublic Information") is strictly confidential and is
being submitted to Purchaser solely for such Purchaser's confidential use in
connection with its investment decision regarding the Securities. Such Purchaser
agrees to use such Nonpublic Information for the sole purpose of evaluating a
possible investment in the Securities and such Purchaser hereby acknowledges
that it is prohibited from reproducing, distributing, divulging or discussing
such Nonpublic Information, in whole or in part, except for use internally and
by its legal counsel and except as required by law or legal process. Such
Purchaser hereby acknowledges that it is aware that the United States securities
laws prohibit any person who has material nonpublic information about a company
from purchasing or selling securities of such company.

            4.6 Shares Not Registered. Such Purchaser understands that none of
the Securities have been registered under the Securities Act, by reason of their
issuance by the Company in a transaction exempt from the registration
requirements of the Securities Act, and that the Securities must continue to be
held by such Purchaser unless a subsequent disposition thereof is registered
under the Securities Act or is exempt from such registration. The Purchaser
understands that the exemptions from registration afforded by Rule 144 (the
provisions of which are known to it) promulgated under the Securities Act depend
on the satisfaction of various conditions, and that, if applicable, Rule 144 may
afford the basis for sales only in limited amounts.

            4.7 No Conflict. The execution and delivery of the Operative
Agreements by such Purchaser and the consummation of the transactions
contemplated thereby will not conflict with or result in any violation of any
provision of the charter or other organizational documents of such Purchaser.

            4.8 Brokers. Such Purchaser has not retained or been represented by
any broker or finder in connection with the transactions contemplated by this
Agreement.

            4.9 Consents. All consents, approvals, orders and authorizations
required on the part of such Purchaser in connection with the execution,
delivery or performance of this Agreement and the consummation of the
transactions contemplated herein have been obtained and are effective as of the
Closing Date.

            4.10 No Intent To Effect a Change of Control. Such Purchaser has no
present intent to change or influence the control of the Company within the
meaning of Rule 13d of the Exchange Act. Such Purchaser will not, immediately
after giving effect to the transactions contemplated hereby, beneficially own
(as such term is defined under the Exchange Act) shares of the Company's capital
stock constituting more than ten percent (10%) of the outstanding voting stock
of the Company.

            4.11 Legends. Each Purchaser understands and agrees that each
certificate in respect of any of the Shares or the Underlying Shares, and each
Warrant, shall be endorsed with a legend substantially in the form set forth
below, and each Purchaser covenants that, except to the extent such restrictions
are waived by the Company, it shall not transfer any Warrants, or any Shares or
Underlying Shares represented by any such certificate, without complying with
the legends endorsed on such certificate:



                                       8


            THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
            UNDER THE SECURITIES ACT OF 1933 OR APPLICABLE STATE SECURITIES LAWS
            (COLLECTIVELY, THE "ACTS"). NO INTEREST IN SUCH SHARES MAY BE SOLD,
            ENCUMBERED OR OTHERWISE TRANSFERRED UNLESS (I) THERE IS AN EFFECTIVE
            REGISTRATION STATEMENT UNDER THE ACTS COVERING THE TRANSACTION, (II)
            THE COMPANY RECEIVES AN OPINION OF COUNSEL SATISFACTORY TO THE
            COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE ACTS, OR
            (III) THE COMPANY OTHERWISE SATISFIES ITSELF THAT REGISTRATION IS
            NOT REQUIRED UNDER THE ACTS.

      5. Conditions Precedent.

            5.1 Conditions to the Obligation of the Purchasers To Consummate the
Closing. The obligation of each Purchaser to consummate the Closing and to
purchase and pay for the Securities being purchased by it pursuant to this
Agreement is subject to the satisfaction of the following conditions precedent:

                  (a) The representations and warranties of the Company
contained herein shall be true and correct on and as of the Closing Date with
the same force and effect as though made on and as of the Closing Date (it being
understood and agreed by each Purchaser that, in the case of any representation
and warranty of the Company contained herein which is not hereinabove qualified
by application thereto of a materiality standard, such representation and
warranty need be true and correct only in all material respects in order to
satisfy as to such representation or warranty the condition precedent set forth
in the foregoing provisions of this Section 5.1(a)).

                  (b) The Registration Rights Agreement shall have been executed
and delivered by the Company.

                  (c) The Company shall not have suffered any Material Adverse
Effect prior to the Closing Date, and the Company shall have performed in all
material respects all obligations and conditions herein required to be performed
or observed by the Company on or prior to the Closing Date.

                  (d) No proceeding challenging this Agreement or the
transactions contemplated hereby, or seeking to prohibit, alter, prevent or
delay the Closing, shall have been instituted before any court, arbitrator or
governmental body, agency or official and shall be pending.

                  (e) The purchase of and payment for the Securities by the
Purchasers shall not be prohibited by any law or governmental order or
regulation. All necessary consents, approvals, licenses, permits, orders and
authorizations of, or registrations, declarations and



                                       9


filings with, any governmental or administrative agency with respect to any of
the transactions contemplated hereby shall have been duly obtained or made and
shall be in full force and effect.

                  (f) Purchasers shall have received a legal opinion from
counsel to the Company in the form attached hereto as Exhibit C.

                  (g) Purchasers shall have received a certificate executed by
the chief executive officer and the chief financial or accounting officer of the
Company, dated the Closing Date, in form and substance reasonably satisfactory
to the Purchasers, to the effect that (i) the representations and warranties of
the Company set forth in Section 3 of this Agreement are true and correct as of
the Closing Date and (ii) the Company has complied in all material respects with
all the agreements and satisfied all the conditions herein on its part to be
performed or satisfied on or prior to such Closing Date.

                  (h) Purchasers shall have received a certificate executed by
the secretary of the Company, dated the Closing Date, certifying as to the
authenticity and effectiveness of the actions of the Company's Board of
Directors in approving the transactions contemplated hereby and the validity of
the Restated Certificate and the Bylaws.

                  (i) Purchasers shall have executed the Agreement for the
purchase of at least $25 million of Securities, and each Purchaser shall have
purchased, in accordance with this Agreement, the number of Shares and Warrants
set forth opposite his, her or its name on Exhibit A.

            5.2 Conditions to the Obligation of the Company To Consummate the
Closing. The obligation of the Company to consummate the Closing and to issue
and sell to each Purchaser the Securities to be purchased by it at the Closing
is subject to the satisfaction of the following conditions precedent:

                  (a) The representations and warranties of such Purchaser
contained herein shall be true and correct on and as of the Closing Date with
the same force and effect as though made on and as of the Closing Date (it being
understood and agreed by the Company that, in the case of any representation and
warranty of each Purchaser contained herein which is not hereinabove qualified
by application thereto of a materiality standard, such representation and
warranty need be true and correct only in all material respects in order to
satisfy as to such representation or warranty the condition precedent set forth
in the foregoing provisions of this Section 5.2(a)).

                  (b) The Registration Rights Agreement shall have been executed
and delivered by each Purchaser.

                  (c) Each Purchaser shall have performed in all material
respects all obligations and conditions herein required to be performed or
observed by the Purchasers on or prior to the Closing Date.

                  (d) No proceeding challenging this Agreement or the
transactions contemplated hereby, or seeking to prohibit, alter, prevent or
delay the Closing, shall have been



                                       10


instituted before any court, arbitrator or governmental body, agency or official
and shall be pending.

                  (e) The sale of the Securities by the Company shall not be
prohibited by any law or governmental order or regulation. All necessary
consents, approvals, licenses, permits, orders and authorizations of, or
registrations, declarations and filings with, any governmental or administrative
agency with respect to any of the transactions contemplated hereby shall have
been duly obtained or made and shall be in full force and effect.

                  (f) Purchasers shall have executed the Agreement for the
purchase of at least $25 million of Securities, and each Purchaser shall have
purchased, in accordance with this Agreement, the number of Shares and Warrants
set forth opposite his, her or its name on Exhibit A.

      6. Termination; Liabilities Consequent Thereon. This Agreement may be
terminated and the transactions contemplated hereunder abandoned at any time
prior to the Closing only as follows:

            (a) by either the Purchasers or the Company if the Closing shall not
have occurred by August 19, 2002; provided, however, that the right to terminate
this Agreement pursuant to this Section 6(a) shall not be available to any party
whose failure to fulfill any obligation under this Agreement has been the cause
of, or resulted in, the failure of the Closing to occur before such date; or

            (b) at any time by mutual agreement of the Company and the
Purchasers; or

            (c) by the Purchasers, if there has been any breach of any
representation or warranty or any material breach of any covenant of the Company
contained herein and the same has not been cured within 15 days after notice
thereof, (it being understood and agreed by each Purchaser that, in the case of
any representation or warranty of the Company contained herein which is not
hereinabove qualified by application thereto of a materiality standard, such
representation or warranty will be deemed to have been breached for purposes of
this Section 6.1(c) only if such representation or warranty was not true and
correct in all material respects at the time such representation or warranty was
made by the Company); or

            (d) by the Company, if there has been any breach of any
representation, warranty or any material breach of any covenant of any Purchaser
contained herein and the same has not been cured within 15 days after notice
thereof (it being understood and agreed by the Company that, in the case of any
representation and warranty of the Purchaser contained herein which is not
hereinabove qualified by application thereto of a materiality standard, such
representation or warranty will be deemed to have been breached for purposes of
this Section 6.1(d) only if such representation or warranty was not true and
correct in all material respects at the time such representation or warranty was
made by such Purchaser).

            Any termination pursuant to this Section 6 shall be without
liability on the part of any party, unless such termination is the result of a
material breach of this Agreement by a party



                                       11


to this Agreement in which case such breaching party shall remain liable for
such breach notwithstanding any termination of this Agreement.

      7. Miscellaneous Provisions.

            7.1 Public Statements or Releases. Prior to the issuance by the
Company of a press release announcing the transaction contemplated by this
Agreement, no Purchaser shall make, issue, or release any announcement, whether
to the public generally, or to any of its suppliers or customers, with respect
to this Agreement or the transactions provided for herein, or make any statement
or acknowledgment of the existence of, or reveal the status of, this Agreement
or the transactions provided for herein, without the prior consent of the
Company.

            7.2 Further Assurances. Each party agrees to cooperate fully with
the other party and to execute such further instruments, documents and
agreements and to give such further written assurances, as may be reasonably
requested by the other party to better evidence and reflect the transactions
described herein and contemplated hereby, and to carry into effect the intents
and purposes of this Agreement.

            7.3 Rights Cumulative. Each and all of the various rights, powers
and remedies of the parties shall be considered to be cumulative with and in
addition to any other rights, powers and remedies which such parties may have at
law or in equity in the event of the breach of any of the terms of this
Agreement. The exercise or partial exercise of any right, power or remedy shall
neither constitute the exclusive election thereof nor the waiver of any other
right, power or remedy available to such party.

            7.4 Pronouns. All pronouns or any variation thereof shall be deemed
to refer to the masculine, feminine or neuter, singular or plural, as the
identity of the person, persons, entity or entities may require.

            7.5 Notices. Any notice required or permitted by this Agreement
shall be in writing and shall be sufficient upon receipt, when delivered
personally or by courier, overnight delivery service or confirmed facsimile, or
forty-eight hours after being deposited in the regular mail as certified or
registered mail (airmail if sent internationally) with postage prepaid, if such
notice is addressed to the party to be notified at such party's address or
facsimile number as set forth below (if to the Company) or as set forth in
Exhibit A (if to a Purchaser), or as subsequently modified by written notice:

            If to the Company:        Corixa Corporation
                                      1124 Columbia Street
                                      Suite 200
                                      Seattle, WA 98104
                                      Facsimile No.: (206) 754-5994
                                      Attn: Michelle Burris



                                       12


            With a copy to:           Orrick, Herrington & Sutcliffe LLP
                                      719 Second Avenue
                                      Suite 900
                                      Seattle, WA 98104
                                      Facsimile No.:  (206) 839-4301
                                      Attn:  Stephen M. Graham
                                             Alan C. Smith

            7.6 Captions. The captions and paragraph headings of this Agreement
are solely for the convenience of reference and shall not affect the
interpretation of this Agreement.

            7.7 Severability. Should any part or provision of this Agreement be
held unenforceable or in conflict with the applicable laws or regulations of any
jurisdiction, the invalid or unenforceable part or provisions shall be replaced
with a provision which accomplishes, to the extent possible, the original
business purpose of such part or provision in a valid and enforceable manner,
and the remainder of this Agreement shall remain binding upon the parties
hereto.

            7.8 Governing Law. This Agreement shall be governed by and construed
in accordance with the internal and substantive laws of the state of Delaware
and without regard to any conflicts of laws concepts which would apply the
substantive law of some other jurisdiction.

            7.9 Waiver. No waiver of any term, provision or condition of this
Agreement, whether by conduct or otherwise, in any one or more instances, shall
be deemed to be, or be construed as, a further or continuing waiver of any such
term, provision or condition or as a waiver of any other term, provision or
condition of this Agreement.

            7.10 Expenses. Each party will bear its own costs and expenses in
connection with this Agreement.

            7.11 Assignment. The rights and obligations of the parties hereto
shall inure to the benefit of and shall be binding upon the authorized
successors and permitted assigns of each party. Neither party may assign its
rights or obligations under this Agreement or designate another person (i) to
perform all or part of its obligations under this Agreement or (ii) to have all
or part of its rights and benefits under this Agreement, in each case without
the prior written consent of the other party. In the event of any assignment in
accordance with the terms of this Agreement, the assignee shall specifically
assume and be bound by the provisions of the Agreement by executing and agreeing
to an assumption agreement reasonably acceptable to the other party.

            7.12 Survival. The respective representations and warranties given
by the parties hereto, and the other covenants and agreements contained herein,
shall survive the Closing Date and the consummation of the transactions
contemplated herein for a period of two years, without regard to any
investigation made by any party.

            7.13 Counterpart. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.



                                       13


            7.14 Entire Agreement; Amendments. This Agreement and the
Registration Rights Agreement constitute and contain the entire agreement and
understanding of the parties with respect to the subject matter hereof, and also
supersede any and all prior negotiations, correspondence, agreements or
understandings with respect to the subject matter hereof. No modification,
alteration, waiver or change in any of the terms of this Agreement shall be
valid or binding upon the parties hereto unless made in writing and duly
executed by the Company and the Majority Purchasers.

                            [Signature Page Follows]



                                       14


      IN WITNESS WHEREOF, the parties hereto have executed this Securities
Purchase Agreement under seal as of the day and year first above written.

                                        THE COMPANY:

                                        CORIXA CORPORATION

                                        By: /s/ STEVEN GILLIS, Ph.D.
                                            ------------------------------------
                                            Name: Steven Gillis, Ph.D.
                                                 -------------------------------
                                            Title: Chairman, CEO
                                                  ------------------------------

                                        Address:      1224 Columbia Street
                                                      Suite 200
                                                      Seattle, WA 98104
                                        Telephone:    (206) 754-5711
                                        Facsimile:    (206) 754-5994

                                        PURCHASERS:

                                        INTERWEST PARTNERS VIII, L.P.
                                        By: InterWest Management Partners VIII,
                                        LLC, its general partner


                                        By: /s/ ARNOLD ORONSKY
                                            ------------------------------------
                                            Name: Arnold L. Oronsky
                                                 -------------------------------
                                            Title: Managing Director
                                                  ------------------------------

                                        Address:      2710 Sand Hill Road
                                                      --------------------------
                                                      Menlo Park, CA 94025
                                                      --------------------------
                                        Telephone:    650-854-8585
                                                      --------------------------
                                        Facsimile:    650-854-4706
                                                      --------------------------

                                        INTERWEST INVESTORS Q VIII, L.P.
                                        By: InterWest Management Partners VIII,
                                        LLC, its general partner


                                        By: /s/ ARNOLD ORONSKY
                                            ------------------------------------
                                            Name: Arnold L. Oronsky
                                                 -------------------------------
                                            Title: Managing Director
                                                  ------------------------------

                                        Address:      2710 Sand Hill Road
                                                      --------------------------
                                                      Second Floor
                                                      --------------------------
                                                      Menlo Park, CA 94025
                                                      --------------------------
                                        Telephone:    650-854-8585
                                                      --------------------------
                                        Facsimile:    650-854-4706
                                                      --------------------------



                                       15


                                        INTERWEST INVESTORS VIII, L.P.
                                        By: InterWest Management Partners VIII,
                                        LLC, its general partner


                                        By: /s/ ARNOLD ORONSKY
                                            ------------------------------------
                                            Name: Arnold L. Oronsky
                                                 -------------------------------
                                            Title: Managing Director
                                                  ------------------------------

                                        Address:      2710 Sand Hill Road
                                                      --------------------------
                                                      Second Floor
                                                      --------------------------
                                                      Menlo Park, CA 94025
                                                      --------------------------
                                        Telephone:    650-854-8585
                                                      --------------------------
                                        Facsimile:    650-854-4706
                                                      --------------------------



                                       16


                                        BAVP, L.P.
                                        By: BA Venture Partners VI, LLC, its
                                        general partner


                                        By: /s/ LOUIS C. BOCK
                                            ------------------------------------
                                            Name: Louis C. Bock
                                                 -------------------------------
                                            Title: Managing Member

                                        Address:      950 Tower Lane Suite 700
                                                      --------------------------
                                                      Foster City, CA 94404
                                                      --------------------------
                                        Telephone:    650-378-6068
                                                      --------------------------
                                        Facsimile:    650-378-6040
                                                      --------------------------

                                        FRAZIER HEALTHCARE IV, L.P.
                                        By: FHM IV, LP, its general partner
                                        By FHM IV, LLC, its general partner



                                        By: /s/ NATHAN EVERY
                                            ------------------------------------
                                            Name: Nathan Every
                                            Title: Authorized Representative

                                        Address:      601 Union St. Suite 3300
                                                      --------------------------
                                                      Seattle, WA 98101
                                                      --------------------------
                                        Telephone:    206-621-7200
                                                      --------------------------
                                        Facsimile:    206-621-1848
                                                      --------------------------



                                       17


                                        FRAZIER AFFILIATES IV, L.P.
                                        By:  FHM IV, LP, its general partner
                                        By FHM IV, LLC, its general partner


                                        By: /s/ NATHAN EVERY
                                            ------------------------------------
                                            Name: Nathan Every
                                            Title: Authorized Representative

                                        Address:      601 Union St. Suite 3300
                                                      --------------------------
                                                      Seattle, WA 98101
                                                      --------------------------
                                        Telephone:    206-621-7200
                                                      --------------------------
                                        Facsimile:    206-621-1848
                                                      --------------------------

                                        KBL HEALTHCARE, L.P.

                                        By:  KBL Healthcare, LLC, its general
                                             partner



                                        By: /s/ MARLENE KRAUSS, M.D.
                                            ------------------------------------
                                            Name: Marlene Krauss, M.D.
                                                 -------------------------------
                                            Title: Managing Director, G.P.
                                                  ------------------------------

                                        Address:      645 Madison Ave.
                                                      --------------------------
                                                      NY, NY 10022
                                                      --------------------------
                                        Telephone:    212-319-5555 Ext. 16
                                                      --------------------------
                                        Facsimile:    212-319-5591
                                                      --------------------------

                                        KBL PARTNERSHIP, L.P.
                                        By:  KBL Healthcare, LLC, its general
                                             partner


                                        By: /s/ MARLENE KRAUSS, M.D.
                                            ------------------------------------
                                            Name: Marlene Krauss, M.D.
                                            Title: Managing Director, G.P.

                                        Address:      645 Madison Ave.
                                                      --------------------------
                                                      NY, NY 10022
                                                      --------------------------
                                        Telephone:    212-319-5555 Ext. 16
                                                      --------------------------
                                        Facsimile:    212-319-5519
                                                      --------------------------



                                       18


                                        OXFORD BIOSCIENCE PARTNERS IV L.P.
                                        By:  OBP Management IV L.P.


                                        By: /s/ JONATHAN J. FLEMING
                                            ------------------------------------
                                            Name: Jonathan J. Fleming
                                            Title: General Partner

                                        Address:   222 Berkeley St., Suite 1650
                                                   -----------------------------
                                                   Boston, MA 02116
                                                   -----------------------------
                                        Telephone: 617-357-7474
                                                   -----------------------------
                                        Facsimile: 617-357-7476
                                                   -----------------------------


                                        MRNA FUND II L.P.
                                        By:  OBP Management IV L.P.


                                        By: /s/ JONATHAN J. FLEMING
                                            ------------------------------------
                                            Name: Jonathan J. Fleming
                                            Title: General Partner

                                        Address:   222 Berkeley St., Suite 1650
                                                   -----------------------------
                                                   Boston, MA 02116
                                                   -----------------------------
                                        Telephone: 617-357-7474
                                                   -----------------------------
                                        Facsimile: 617-357-7476
                                                   -----------------------------



                                       19


                                      SUTTER HILL VENTURES,
                                      A CALIFORNIA LIMITED PARTNERSHIP

                                      By: /s/ TENCH COXE
                                          ------------------------------------
                                          Name:  Tench Coxe
                                               -------------------------------
                                          Title: Managing Director of the
                                                 General Partner

                                      Address:   755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                      Telephone: 650-493-5600
                                                 -------------------------------
                                      Facsimile: 650-858-1854
                                                 -------------------------------

                                      SUTTER HILL ENTREPRENEURS FUND (AI),
                                      L.P.


                                      By: /s/ TENCH COXE
                                          ------------------------------------
                                          Name:  Tench Coxe
                                               -------------------------------
                                          Title: Managing Director of the
                                                 General Partner

                                      Address:   755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                      Telephone: 650-493-5600
                                                 -------------------------------
                                      Facsimile: 650-858-1854
                                                 -------------------------------


                                      SUTTER HILL ENTREPRENEURS FUND (QP),
                                      L.P.


                                      By: /s/ TENCH COXE
                                          ------------------------------------
                                          Name:  Tench Coxe
                                               -------------------------------
                                          Title: Managing Director of the
                                                 General Partner

                                      Address:   755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                      Telephone: 650-493-5600
                                                 -------------------------------
                                      Facsimile: 650-858-1854
                                                 -------------------------------




                                       20


                                        G. LEONARD BAKER, JR.

                                        /s/ DAVID E. SWEET
                                        ----------------------------------------
                                        By  David E. Sweet
                                        Under Power of Attorney
                                        ----------------------------------------
                                        G. Leonard Baker, Jr.

                                        Address: 755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        SAUNDERS HOLDINGS, L.P.

                                        By: /s/ DAVID E. SWEET
                                            ------------------------------------
                                            By  David E. Sweet
                                            Under Power of Attorney
                                            ------------------------------------
                                            Name: G. Leonard Baker, Jr.
                                            Title: General Partner

                                        Address: 755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        THE COXE/OTUS REVOCABLE TRUST U/A/D
                                        4/23/98


                                        By: /s/ TENCH COXE
                                            ------------------------------------
                                            Name: Tench Coxe
                                            Title: Trustee

                                        Address: 755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        YIN FAMILY TRUST DATED
                                        MARCH 1, 1997

                                        By: /s/ ROBERT YIN
                                            ------------------------------------
                                            Name:  Robert Yin
                                            Title: Trustee

                                        Address: 755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------



                                       21


                                        JEFFREY W. BIRD AND CHRISTINA R. BIRD
                                        TRUST AGREEMENT DATED OCTOBER 31, 2000

                                        By: /s/ DAVID E. SWEET
                                            ------------------------------------
                                            By  David E. Sweet
                                            Under Power of Attorney
                                            ------------------------------------
                                            Name:  Jeffrey W. Bird
                                            Title: Trustee

                                        Address: 755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        THE BERNAL FAMILY TRUST U/D/T
                                        NOVEMBER 3, 1995, RONALD D. BERNAL AND
                                        PAMELA M. BERNAL, TRUSTEES


                                        By: /s/ DAVID E. SWEET
                                            ------------------------------------
                                            By  David E. Sweet
                                            Under Power of Attorney
                                            ------------------------------------
                                            Name:  Ronald D. Bernal
                                            Title: Trustee

                                        Address: 755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        JAMES C. GAITHER

                                        /s/ JAMES C. GAITHER
                                        ----------------------------------------
                                        James C. Gaither

                                        Address: 755 Page Mill Road, Suite A-200
                                                 -------------------------------
                                                 Palo Alto, CA 94304-1005
                                                 -------------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------



                                       22


                                        THE GREGORY P. AND SARAH J.D. SANDS
                                        TRUST AGREEMENT DATED 2/24/99


                                        By: /s/ GREGORY SANDS
                                            ------------------------------------
                                            Name:  Gregory P. Sands
                                            Title: Trustee

                                        Address:      755 Page Mill Road, Suite
                                                      A-200
                                                      --------------------------
                                                      Palo Alto, CA 94304-1005
                                                      --------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        DAVID E. SWEET

                                        /s/ DAVID E. SWEET
                                        ----------------------------------------
                                        David E. Sweet

                                        Address:      755 Page Mill Road, Suite
                                                      A-200
                                                      --------------------------
                                                      Palo Alto, CA 94304-1005
                                                      --------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        LYNNE M. BROWN

                                        /s/ LYNNE M. BROWN
                                        ----------------------------------------
                                        Lynne M. Brown

                                        Address:      755 Page Mill Road, Suite
                                                      A-200
                                                      --------------------------
                                                      Palo Alto, CA 94304-1005
                                                      --------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------

                                        PATRICIA TOM

                                        /s/ PATRICIA TOM
                                        ----------------------------------------
                                        Patricia Tom

                                        Address:      755 Page Mill Road, Suite
                                                      A-200
                                                      --------------------------
                                                      Palo Alto, CA 94304-1005
                                                      --------------------------
                                        Telephone:    650-493-5600
                                                      --------------------------
                                        Facsimile:    650-858-1854
                                                      --------------------------



                                       23


                                   WELLS FARGO BANK, TRUSTEE
                                   SHV M/P/T FBO
                                   SHERRYL W. HOSSACK


                                   By: /s/ VICKI M. BANDEL     /s/ EVAN HODGENS
                                       ----------------------------------------
                                       Name: Vicki M. Bandel       Evan Hodgens
                                            -----------------------------------
                                       Title: AVP & TO             Vice Pres.
                                             ----------------------------------

                                   Address:      420 Montgomery St.
                                                 2nd Floor
                                                 ------------------------------
                                                 San Francisco, CA 94104
                                                 ------------------------------
                                   Telephone:    415-396-3739
                                                 ------------------------------
                                   Facsimile:    415-956-9362
                                                 ------------------------------



                                   WELLS FARGO BANK, TRUSTEE
                                   SHV M/P/T FBO
                                   DAVID L. ANDERSON


                                   By: /s/ VICKI M. BANDEL     /s/ EVAN HODGENS
                                       ----------------------------------------
                                       Name: Vicki M. Bandel       Evan Hodgens
                                            -----------------------------------
                                       Title: AVP & TO             Vice Pres.
                                             ----------------------------------

                                   Address:      420 Montgomery St.
                                                 2nd Floor
                                                 ------------------------------
                                                 San Francisco, CA 94104
                                                 ------------------------------
                                   Telephone:    415-396-3739
                                                 ------------------------------
                                   Facsimile:    415-956-9362
                                                 ------------------------------


                                   WELLS FARGO BANK, TRUSTEE
                                   SHV M/P/T FBO
                                   DAVID E. SWEET (ROLLOVER)


                                   By: /s/ VICKI M. BANDEL     /s/ EVAN HODGENS
                                       ----------------------------------------
                                       Name: Vicki M. Bandel       Evan Hodgens
                                            -----------------------------------
                                       Title: AVP & TO             Vice Pres.
                                             ----------------------------------

                                   Address:      420 Montgomery St.
                                                 2nd Floor
                                                 ------------------------------
                                                 San Francisco, CA 94104
                                                 ------------------------------
                                   Telephone:    415-396-3739
                                                 ------------------------------
                                   Facsimile:    415-956-9362
                                                 ------------------------------



                                       24


                                   WELLS FARGO BANK, TRUSTEE
                                   SHV M/P/T FBO
                                   JAMES N. WHITE (ROLLOVER)


                                   By: /s/ VICKI M. BANDEL     /s/ EVAN HODGENS
                                       ----------------------------------------
                                       Name: Vicki M. Bandel       Evan Hodgens
                                            -----------------------------------
                                       Title: AVP & TO             Vice Pres.
                                             ----------------------------------

                                   Address:      420 Montgomery St.
                                                 2nd Floor
                                                 ------------------------------
                                                 San Francisco, CA 94104
                                                 ------------------------------
                                   Telephone:    415-396-3739
                                                 ------------------------------
                                   Facsimile:    415-956-9362
                                                 ------------------------------


                                   WELLS FARGO BANK, TRUSTEE
                                   SHV M/P/T FBO
                                   WILLIAM H. YOUNGER, JR.


                                   By: /s/ VICKI M. BANDEL     /s/ EVAN HODGENS
                                       ----------------------------------------
                                       Name: Vicki M. Bandel       Evan Hodgens
                                            -----------------------------------
                                       Title: AVP & TO             Vice Pres.
                                             ----------------------------------

                                   Address:      420 Montgomery St.
                                                 2nd Floor
                                                 ------------------------------
                                                 San Francisco, CA 94104
                                                 ------------------------------
                                   Telephone:    415-396-3739
                                                 ------------------------------
                                   Facsimile:    415-956-9362
                                                 ------------------------------



                                       25


                                        H&Q LIFE SCIENCE INVESTORS

                                        By: /s/ DANIEL R. OMSTEAD
                                            ------------------------------------
                                            Name:  Daniel R. Omstead
                                            Title: President

                                        Address:      30 Rowes Wharf
                                                      --------------------------
                                                      Boston, MA 02110
                                                      --------------------------
                                        Telephone:    617-310-0415
                                                      --------------------------
                                        Facsimile:    617-310-0562
                                                      --------------------------

                                        The name H&Q Life Science Investors is
                                        the designation of the Trustees for the
                                        time being under an Amended and Restated
                                        Declaration of Trust Dated February 20,
                                        1992, as amended, and all persons
                                        dealing with H&Q Life Science Investors
                                        must look solely to the trust property
                                        for the enforcement of any claim against
                                        H&Q Life Science Investors, as neither
                                        the Trustees, officers nor shareholders
                                        assume any personal liability for
                                        obligations entered into on behalf of
                                        H&Q Life Science Investors.

                                        H&Q HEALTHCARE INVESTORS

                                        By: /s/ DANIEL R. OMSTEAD
                                            ------------------------------------
                                            Name:  Daniel R. Omstead
                                            Title: President

                                        Address:      30 Rowes Wharf
                                                      --------------------------
                                                      Boston, MA 02110
                                                      --------------------------
                                        Telephone:    617-310-0415
                                                      --------------------------
                                        Facsimile:    617-310-0562
                                                      --------------------------


                                        The name H&Q Healthcare Investors is the
                                        designation of the Trustees for the time
                                        being under an Amended and Restated
                                        Declaration of Trust Dated April 21,
                                        1987, as amended, and all persons
                                        dealing with H&Q Healthcare Investors
                                        must look solely to the trust property
                                        for the enforcement of any claim against
                                        H&Q Healthcare Investors, as neither the
                                        Trustees, officers nor shareholders
                                        assume any personal liability for
                                        obligations entered into on behalf of
                                        H&Q Healthcare Investors.



                                       26


                                    EXHIBIT A

                                   PURCHASERS

NUMBER OF NUMBER OF SHARES WARRANTS TO BE AGGREGATE PURCHASER TO BE PURCHASED PURCHASED PURCHASE PRICE - ---------------------------------------- ---------------- -------------- -------------- InterWest Partners VIII, L.P. 2,352,469 399,920 $14,470,624.94 InterWest Investors VIII, L.P. 18,777 3,192 115,502.02 InterWest Investors Q VIII, L.P. 67,304 11,442 414,003.73 BAVP, L.P. 1,632,189 277,472 10,040,002.59 Frazier Healthcare IV, L.P. 808,738 137,485 4,974,749.62 Frazier Affiliates IV, L.P. 4,105 698 25,250.88 KBL Healthcare, L.P. 436,000 74,120 2,681,945.00 KBL Partnership, L.P. 52,000 8,840 319,865.00 Oxford Bioscience Partners IV L.P. 804,768 136,811 4,950,331.67 MRNA Fund II L.P. 8,075 1,373 49,671.34 H&Q Healthcare Investors 195,082 33,164 1,199,998.15 H&Q Life Science Investors 130,055 22,109 800,000.81 Sutter Hill Ventures, A California Limited Partnership 567,811 96,528 3,492,747.41 Sutter Hill Entrepreneurs Fund (AI), L.P. 5,616 955 34,545.42 Sutter Hill Entrepreneurs Fund (QP), L.P. 14,220 2,417 87,470.78 G. Leonard Baker, Jr. 13,712 2,331 84,345.94 Saunders Holdings, L.P. 13,712 2,331 84,345.94 The Coxe/Otus Revocable Trust, U/A/D 4/23/98 - Tench Coxe, Trustee 66,599 11,322 409,667.10
Yin Family Trust Dated March 1, 1997 - Robert Yin, Trustee 1,016 173 6,249.67 Jeffrey W. Bird and Christina R. Bird Trust Agreement Dated October 31, 2000 - Jeffrey W. Bird, Trustee 8,130 1,382 50,009.66 The Bernal Family Trust U/D/T November 3, 1995 - Ronald D. Bernal and Pamela M. Bernal, Trustees 8,130 1,382 50,009.66 James C. Gaither 11,753 1,998 72,295.64 The Gregory P. and Sarah J.D. Sands Trust Agreement dated 2/24/99 - Gregory P. and Sarah J.D. Sands, Trustees 11,753 1,998 72,295.64 David E. Sweet 4,065 691 25,004.83 Lynne M. Brown 1,016 173 6,249.67 Patricia Tom 1,016 173 6,249.67 Wells Fargo Bank, Trustee SHV M/P/T FBO Sherryl W. Hossack 2,033 345 12,505.49 Wells Fargo Bank, Trustee SHV M/P/T FBO David L. Anderson 19,588 3,330 120,490.69 Wells Fargo Bank, Trustee SHV M/P/T FBO David E. Sweet (Rollover) 4,065 691 25,004.83 Wells Fargo Bank, Trustee SHV M/P/T FBO William H. Younger, Jr 47,012 7,992 289,182.57 Wells Fargo Bank, Trustee SHV M/P/T FBO James N. White (Rollover) 11,753 1,998 72,295.64
2 TOTAL 7,322,562 1,244,836 $45,042,909.50
3 APPENDIX I CORIXA CORPORATION PURCHASER QUESTIONNAIRE Pursuant to Section 2.2 of the Securities Purchase Agreement, please provide us with the following information: 1. The exact name that your Shares and Warrants are to be registered in (this is the name that will appear on your stock certificate(s)). You may use a nominee name if appropriate: ---------------------------------- 2. The relationship between the Purchaser of the Shares and Warrants and the Registered Holder listed in response to item 1 above: ______________ ___________________ 3. The mailing address of the Registered Holder listed in response to item 1 above: ---------------------------------- ---------------------------------- ---------------------------------- ---------------------------------- 4. The Social Security Number or Tax Identification Number of the Registered Holder listed in response to item 1 above: ----------------------------------