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                                                                    EXHIBIT 10.1

                          SECURITIES PURCHASE AGREEMENT

         This SECURITIES PURCHASE AGREEMENT (this "Agreement") is dated as of
the 8th day of June, 2003, 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 shares
(the "Shares") of the authorized but unissued shares of common stock, $.001 par
value per share, of the Company (the "Common Stock") and warrants in the form
attached as Exhibit B to purchase 0.18 shares of Common Stock for each Share
(each, a "Warrant," and collectively, the "Warrants") at an aggregate purchase
price of approximately $30,000,000;

         WHEREAS, the Company proposes to complete an offering of not less than
$75,000,000 aggregate principal amount of convertible notes (the "Convertible
Notes") on or before June 15, 2003; 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" (including the terms "controlling,"
"controlled by" and "under common control with") shall mean the possession,
direct or indirect, of the power to direct or cause the direction of the
management and policies of a person or entity, whether through the ownership of
voting securities, by contract, or otherwise.

                  (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)               "Fair Market Value" shall mean (i) the
average of the closing bid prices on the Nasdaq National Market for the five
trading days immediately preceding and including the date on which the condition
set forth in Section 5.1(i) has been satisfied or waived, if such condition is
satisfied or waived after 4:30 p.m. Eastern time on such date, or (ii) the
average of the closing bid prices on the Nasdaq National Market for the five
trading days immediately preceding but not including the date on which the
condition set forth in Section 5.1(i) has been satisfied or waived, if such
condition is satisfied or waived before 4:30 p.m. Eastern time on such date.

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

                  (f)               "Material Adverse Effect" shall mean any
change, effect, event, occurrence, development or developments which,
individually or in the aggregate, (i) has had or would reasonably be expected to
have a material adverse effect on the business, assets, liabilities (contingent
or other), affairs, operations or financial condition of the Company or its
Subsidiary, or (ii) would reasonably be expected to prevent or materially
impede, interfere, hinder or delay the performance by the Company of its
obligations hereunder.

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

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

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

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

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

                  (l)               "Subsidiary" shall mean a subsidiary of the
Company that is an Affiliate of the Company.

                  (m)               "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, for an aggregate purchase price set
forth opposite the name of such Purchaser on Exhibit A hereto, Shares at a
purchase price per Share equal to the Fair Market Value, and a Warrant to
purchase 0.18 shares of Common Stock for every one Share purchased by the
Purchaser at a purchase price per Underlying Share of $0.125 and having an
exercise price per Underlying Share equal to the Fair Market Value. The
aggregate purchase price payable by the Purchasers to the Company for all of the
Securities purchased at the Closing shall be approximately $30,000,000.

                  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 either (a) the date that is
four business days after the date on which the condition set forth in

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Section 5.1(i) has been satisfied or waived, if such condition is satisfied or
waived after 4:30 p.m. Eastern time on such date, or (b) the date that is three
business days after the date on which the condition set forth in Section 5.1(i)
has been satisfied or waived, if such condition is satisfied or waived before
4:30 p.m. Eastern time on such date, 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 Filed SEC Documents (as defined below)(including the
documents incorporated by reference therein) and the Company's press releases
since March 31, 2003 that are currently available on the Company's web site
located at http://www.corixa.com, the Company hereby represents and warrants to,
and covenants with, each of the Purchasers as follows:

                  3.1      Incorporation. Each of the Company and its Subsidiary
is a corporation duly organized, validly existing and in good standing under the
laws of the state of Delaware and is qualified to do 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. Complete and
correct copies of the Company's Amended and Restated Certificate of
Incorporation (the "Restated Certificate") and its Bylaws (the "Bylaws"), and
the certificate of incorporation and bylaws of its Subsidiary, as in effect on
the date hereof, have been filed by the Company with the SEC or otherwise made
available (including via EDGAR) to the Purchasers. The Company and its
Subsidiary have all requisite corporate power and authority to carry on its
business as now conducted.

                  3.2      Subsidiaries. Exhibit 21.1 to the Company's Annual
Report on Form 10-K for the fiscal year ended December 31, 2002 lists the
Company's only Subsidiary. The Subsidiary is incorporated in Delaware and is
qualified to do business in the state of California., As of the date hereof,
the Subsidiary is not qualified or licensed to do business in any other
jurisdiction. All of the issued and outstanding shares of capital stock of, or
other equity interests in, the Subsidiary have been validly issued and are fully
paid and nonassessable and are owned by the Company free and clear of all
pledges, liens, charges, encumbrances or security interests of any kind
("Liens"), and free of any restriction on the right to vote, sell or otherwise
dispose of such capital stock or other equity interests. Except for the capital
stock of, or voting securities or equity interests in, its Subsidiary and 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.

                  3.3      Capitalization. The authorized capital stock of the
Company consists of (i) 100,000,000 shares of Common Stock, of which 51,097,456
shares were outstanding as of

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June 1, 2003 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 1, 2003. The Company has not issued any capital stock
since June 1, 2003 other than pursuant to employee benefit plans disclosed in
the Filed 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.

                  3.4      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 applicable 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.

                  3.5      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 therefor, the Underlying Shares will be
validly issued, fully paid and 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").

                  3.6      Financial Statements. The Company has made available
(including via EDGAR) to each Purchaser its audited Consolidated Statements of
Income, Stockholders' Equity and Cash Flows for the fiscal year ended December
31, 2002, its audited Consolidated Balance Sheet as of December 31, 2002, its
unaudited Consolidated Statements of Income, Stockholders' Equity and Cash Flows
for the period from January 1, 2003 through March 31, 2003 and its unaudited
Consolidated Balance Sheet as of March 31, 2003. All such financial statements
are

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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 its Subsidiary and
the results of their respective 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 and its Subsidiary have implemented and maintain a system of internal
accounting controls meeting the requirements of applicable law, including
without limitation the requirements of Section 13(b)(2) of the Exchange Act.
Since March 31, 2003, there has been no Material Adverse Effect.

                  3.7      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,
2002, the Company's Quarterly Report on Form 10-Q for the three months ended
March 31, 2003, the Company's Definitive Proxy Statement for the Annual Meeting
held on May 30, 2003 and the Company's Current Reports on Form 8-K filed after
December 31, 2002 and before the date hereof (all such materials being called,
collectively, the "Filed SEC Documents"). The Company will, promptly upon the
filing thereof, also make available 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 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 Filed SEC Documents
complied, and the SEC Documents will comply, in all material respects with the
requirements of the Exchange Act, and none of the Filed SEC Documents, as of
their respective filing dates, contained, and none of the SEC Documents will
contain, any untrue statement of a material fact or omitted or omit, as the case
may be, 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 or are, as the case may be, made, not misleading, except to the
extent corrected by a subsequent Filed SEC Document.

                  3.8      Consents. All consents, approvals, orders,
authorizations and filings 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.

                  3.9      No Conflict. The execution and delivery of the
Operative Agreements by the Company and the performance by the Company of its
obligations thereunder 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 or its Subsidiary is a party or by which either of their

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respective 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 Subsidiary or their respective properties or
assets.

                  3.10     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.

                  3.11     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.

                  3.12     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 Filed 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.

                  3.13     Intellectual Property.

                           (a)      To the knowledge of the Company, the Company
and its Subsidiary have 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 their respective businesses and material to
the Company or its Subsidiary (collectively, "Intellectual Property"), other
than Intellectual Property generally available on commercial terms from other
sources.

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

                           (c)      The Company believes it and its Subsidiary
have taken those steps required in accordance with sound business practice and
commercially reasonable business judgment to establish and preserve the
ownership by the Company and its Subsidiary of all

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material patent, copyright, trade secret and other proprietary rights with
respect to their respective products and technology.

                           (d)      To the knowledge of the Company, the present
business, activities and products of the Company and its Subsidiary 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 or its Subsidiary 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 or its
Subsidiary in the conduct of their respective businesses as currently conducted
and as proposed to be conducted in the Filed SEC Documents, where such
infringement would have a Material Adverse Effect. To the knowledge of the
Company, neither the Company nor its Subsidiary is making unauthorized use of
any confidential information or trade secrets of any person, except for such
unauthorized uses that would not reasonably be expected have a Material Adverse
Effect. Neither the Company, its Subsidiary nor, to the knowledge of the
Company, any of their respective employees have any agreements or arrangements
with any persons other than the Company or its Subsidiary restricting the
Company's, its Subsidiary's or any such employee's engagement in business
activities that are material aspects of the Company's or its Subsidiary's
business as currently conducted or as proposed to be conducted in the Filed SEC
Documents.

                  3.14     Offering Materials. Other than the Filed 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.

                  3.15     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.

                  3.16     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.

                  3.17     No Violations. Neither the Company nor its Subsidiary
is in violation of its organizational documents, or in violation of any law,
administrative regulation, ordinance or order of any court, governmental agency,
self-regulatory organization, arbitration panel or authority applicable to it,
which violation, individually or in the aggregate, would be reasonably expected
to have a Material Adverse Effect, and neither is 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 or its Subsidiary is a
party or by which the Company or its Subsidiary is bound or by

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which the property of the Company or its Subsidiary is bound, which would be
reasonably expected to have a Material Adverse Effect.

                  3.18     Title to Assets. The Company and its Subsidiary have
good and marketable title to all real properties and other properties and assets
owned by them, in each case free from Liens that would materially affect the
value thereof or materially interfere with the use made or to be made thereof by
them, with such exceptions as would not, individually or in the aggregate, have
a Material Adverse Effect. The Company and its Subsidiary hold all leased real
or personal property under valid and enforceable leases with no exceptions that
would, individually or in the aggregate, have a Material Adverse Effect.

                  3.19     Permits. The Company and its Subsidiary possess
adequate certificates, authorities or permits issued by appropriate governmental
agencies or bodies necessary to conduct the business now operated by them (each,
a "Permit"), except where the failure to possess any such Permit or Permits
would not, individually or in the aggregate, have a Material Adverse Effect.
Neither the Company nor its Subsidiary have received any notice of proceedings
relating to the revocation or modification of any Permit that, if determined
adversely to the Company or its Subsidiary, would, individually or in the
aggregate, have a Material Adverse Effect.

                  3.20     Insurance. The Company maintains insurance against
such losses and risks and in such amounts as the Company believes in good faith
is adequate, prudent and customary for the businesses in which the Company and
its Subsidiary are engaged.

                  3.21     Material Agreements. Except as filed with or listed
in the exhibit index to the Filed SEC Documents or as otherwise made available
to the Purchasers, neither Company nor its Subsidiary is a party to any material
contract, as such contracts are defined in Item 601(a)(10) of Regulation S-K
under the Securities Act (each such contract, a "Company Contract"). To the
Company's knowledge, each Company Contract is valid, binding and in full force
and effect and is enforceable by the Company or its Subsidiary in accordance
with its terms, subject to applicable bankruptcy, insolvency, reorganization or
other laws affecting creditors' rights generally and by general equitable
principles. As of the date hereof, no party to any such Company Contract has
notified the Company or its Subsidiary that it intends to terminate such Company
Contract. The Company or its Subsidiary, as the case may be, has performed in
all respects all obligations required to be performed by it to date under the
Company Contracts and is not (with or without the lapse of time or the giving of
notice, or both) in breach or default in any respect thereunder and, to the
knowledge of Company, no other party to any of the Company Contracts, as of the
date hereof, is (with or without the lapse of time or the giving of notice, or
both) in breach or default in any respect thereunder, except to the extent that
such breach or default would not have a Material Adverse Effect.

                  3.22     Related Party Transactions. None of the officers or
directors of the Company or its Subsidiary and, to the knowledge of the Company,
none of their respective employees is presently a party to any transaction with
the Company or its Subsidiary, including any contract, agreement or other
arrangement providing for the furnishing of services to or by, providing for
rental of real or personal property to or from, or otherwise requiring payments
to or from any officer, director or such employee or, to the knowledge of the
Company, any entity in

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which any officer, director, or any such employee has a substantial interest or
is an officer, director, trustee or partner.

                  3.23     Taxes. The Company and its Subsidiary have timely
made or filed all federal, state and foreign income and all other tax returns,
reports and declarations required by any jurisdiction to which they are subject
(unless and only to the extent that the Company and its Subsidiary have set
aside on their respective or consolidated books provisions reasonably adequate
for the payment of all unpaid and unreported taxes) and have timely paid all
taxes and other governmental assessments and charges that are material in
amount, shown or determined to be due on such returns, reports and declarations,
except those being contested in good faith, and have set aside on its books
provisions reasonably adequate for the payment of all taxes for periods
subsequent to the periods to which such returns, reports or declarations apply.
To the knowledge of the Company, there are no unpaid taxes in any material
amount claimed to be due by the taxing authority of any jurisdiction, and the
Company knows of no basis for any such claim. Neither the Company nor its
Subsidiary has executed a waiver with respect to the statute of limitations
relating to the assessment or collection of any foreign, federal, state or local
tax. None of the Company's or its Subsidiary's tax returns is presently being
audited by any taxing authority.

                  3.24     BEXXAR Therapy. BEXXAR therapy is being developed and
tested, and all applications for the approval thereof are, in substantial
compliance with applicable law and regulations issued and enforced by U.S. Food
and Drug Adminsistration (the "FDA"), including the Federal Food, Drug and
Cosmetics Act and the regulations thereunder. The Company is not aware of any
facts which it believes are reasonably likely to cause the nonapproval or denial
of its Biologics License Application currently under review by the FDA for
treatment of non-Hodgkins lymphoma.

         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.

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                  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 Filed SEC Documents, any nonpublic 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
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, except as required to comply with applicable law or legal
process, or except to the extent that such Nonpublic Information becomes
publicly disclosed by the Company or a third party (other than as a result of a
breach hereof by such Purchaser). 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.

                                       10

<PAGE>

                  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-1 of the Exchange Act, except for such
influence that may arise by reason of the board designee of the Majority
Purchasers, as contemplated hereby. 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:

                  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

                                       11

<PAGE>

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

                           (g)      The 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)      The 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)      The Company shall have executed and
delivered a definitive Purchase Agreement (the "Notes Purchase Agreement")
related to the offer and sale of Convertible Notes for aggregate proceeds to the
Company of not less than $75,000,000.

                           (j)      The Company shall have increased the size of
its board of directors to eight (8) directors and shall have appointed Ronald M.
Hunt to the directorship created by such increase.

                  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

                                       12

<PAGE>

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 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.

         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 June 30, 2003; provided, however, that
the right to terminate this Agreement pursuant to this Section 7(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

                                       13

<PAGE>

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 7 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 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 (which press release shall be reasonably acceptable to the
Purchasers), 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, and to take such
further actions, 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; Interpretations. 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. The definitions contained in this Agreement are applicable to the
singular as well as the plural. whenever the words "include," "includes" or
"including" are used in this Agreement, they shall be deemed to be followed by
the words "without limitation."

                                       14

<PAGE>

                  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

                  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. Except as provided herein or in the
Registration Rights Agreement, each party will bear its own costs and expenses
in connection with this Agreement; provided, however, that the Company shall pay
the reasonable fees and expenses of the legal advisors (including anticipated
legal fees for preparation and filing of any required Schedule 13D

                                       15

<PAGE>

and Form 4) and due diligence consultants for the Purchasers, in an aggregate
amount not in excess of $100,000.

                  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, 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.

                  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]

                                       16

<PAGE>

         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
                                             Name:   Steven Gillis
                                             Title:  CEO

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

                                             PURCHASERS:

                                             SPROUT IX PLAN INVESTORS, L.P.

                                             By DLJ LBO Plans Management
                                             Corporation II, its General Partner

                                             By: /s/ Ronald M. Hunt
                                                 Ronald M. Hunt
                                                 Its: Attorney in Fact

                                             Address:  Eleven Madison Ave.,
                                                       NY, NY 10010-3629

                                             Telephone: 212-538-8667
                                             Facsimile: 212-538-8245

                                       17

<PAGE>

                                             SPROUT ENTREPRENEURS FUND, L.P.

                                             By DLJ Capital Corporation, its
                                             General Partner

                                             By: /s/ Ronald M. Hunt
                                                 _______________________________
                                                 Ronald M. Hunt
                                                 Its: Director

                                             Address:   Eleven Madison Ave
                                                        ________________________
                                                        NY, NY 10010-3629
                                                        ________________________
                                             Telephone: 212-538-8667
                                                        ________________________
                                             Facsimile: 212-538-8245
                                                        ________________________

                                             SPROUT CAPITAL IX, L.P.

                                             By DLJ Capital Corporation, its
                                             General Partner

                                             By: /s/ Ronald M. Hunt
                                                 _______________________________
                                                 Ronald M. Hunt
                                                 Its: Director

                                             Address:   Eleven Madison Ave
                                                        ________________________
                                                        NY, NY 10010-3629
                                                        ________________________
                                             Telephone: 212-538-8667
                                                        ________________________
                                             Facsimile: 212-538-8245
                                                        ________________________

                                             DLJ CAPITAL CORPORATION

                                             By: /s/ Ronald M. Hunt
                                                 _______________________________
                                                 Ronald M. Hunt
                                                 Its: Director

                                             Address:   Eleven Madison Ave
                                                        ________________________
                                                        NY, NY 10010-3629
                                                        ________________________
                                             Telephone: 212-538-8667
                                                        ________________________
                                             Facsimile: 212-538-8245
                                                        ________________________

                                       18

<PAGE>

                                    EXHIBIT A

                                   PURCHASERS

<TABLE>
<CAPTION>
                                        AGGREGATE PURCHASE PRICE
         PURCHASER                           (APPROXIMATE)
----------------------------------------------------------------
<S>                                     <C>
Sprout IX Plan Investors, L.P.               $  1,316,544
----------------------------------------------------------------

Sprout Entrepreneurs Fund, L.P.              $    112,352
----------------------------------------------------------------

Sprout Capital IX, L.P.                      $ 28,508,618
----------------------------------------------------------------

DLJ Capital Corporation                      $     62,486
----------------------------------------------------------------

TOTAL                                        $ 30,000,000
----------------------------------------------------------------
</TABLE>

<PAGE>

                                   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:
         ___________________________________