<PAGE>

                                                                  EXHIBIT 10.15

*Certain confidential information contained in this document, marked by
brackets, has been omitted and filed with the Securities and Exchange Commission
pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended.

                                 AMENDMENT No. 2

         This Amendment No. 2 (this "Amendment No. 2") to the Multi-Field
Vaccine Discovery Collaboration and License Agreement is entered into by and
between SmithKline Beecham plc ("GSK") and Corixa Corporation ("Corixa") as of
January 28, 2003 (the "Amendment Date").

                                   WITNESSETH:

         WHEREAS, GSK and Corixa entered into that certain Multi-Field Vaccine
Discovery Collaboration and License Agreement dated September 1, 1998, as
amended by Amendment No. 1 dated May 25, 2000, as further amended by that
certain letter agreement by and between the parties dated November 30, 2000, and
as further amended by those certain letter agreements by and between the parties
dated: (i) January 21, 2000, (ii) September 1, 2000, (iii) a further letter
agreement dated September 1, 2000, (iv) November 30, 2000, (v) August 16, 2001,
(vi) April 17, 2002, (vii) October 14, 2002 and (viii) a further letter
agreement dated October 14, 2002 (the "Multi-Field Agreement") pursuant to
which, among other things, Corixa granted certain rights and licenses to GSK
under Corixa rights in technology and substances that may be useful across
several disease indications;

         WHEREAS, GSK and Corixa entered into that certain Corixa License
Agreement as of the date hereof, pursuant to which, among other things, GSK
licensed back to Corixa certain rights licensed to GSK under the Multi-Field
Agreement, including without limitation, the right to develop certain products
for certain indications, subject to certain rights and options included for the
benefit of GSK (the "Corixa Takeaway Agreement");

         WHEREAS, GSK and Corixa entered into that certain Collaboration
Agreement as of the date hereof, pursuant to which, among other things, GSK
licensed back to Corixa certain rights licensed to GSK under the Multi-Field
Agreement, including without limitation, the right to develop certain products
for certain indications, subject to certain rights and licenses included for the
benefit of GSK (the "Collaboration Agreement" and collectively with the Corixa
Takeaway Agreement, the "New Agreements");

         WHEREAS, the New Agreements, by their terms, supersede certain of the
rights and obligations of the parties under the Multi-Field Agreement and such
rights and obligations under the Multi-Field Agreement are intended to be
terminated or suspended, in order to give full and binding effect to the New
Agreements;

         WHEREAS, under certain circumstances set forth in the New Agreements,
certain of the rights and obligations of the parties under the New Agreements
may terminate and in that case

<PAGE>

the parties desire that suspended rights or obligations of the parties under the
Multi-Field Agreement shall again become operative, binding and enforceable; and

         WHEREAS, GSK and Corixa desire to further amend the Multi-Field
Agreement as set forth herein.

         NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto, intending to be legally bound, hereby agree as
follows:

         1.       Certain Definitions. Capitalized terms that are not defined
herein shall be ascribed the meaning given to them under the Multi-Field
Agreement.

         2.       Confirmation of Certain Facts. For the avoidance of doubt, and
in order to aid in the interpretation of the parties' current rights and
obligations under the Multi-Field Agreement, the parties hereby agree to the
following statements of fact as of the Amendment Date:

                  (i)      All R&D Programs have been completed, or are
         otherwise terminated, and all R&D Program Terms are terminated, with
         the exception of the R&D Programs listed on Exhibit 2(i), which shall
         terminate on the dates indicated on such exhibit, unless extended as
         provided for under the Multi-Field Agreement.

                  (ii)     The Parties acknowledge and confirm that an Antigen
         and/or a Product based on or incorporating such Antigen which has been
         first discovered in a R&D Program directed to the BC Field, PC Field,
         OC Field, CC Field or Her2/neu-Mammaglobin Field may be developed and
         commercialized by the Party having rights to such Antigen and/or
         Product under the Multi-Field Agreement as amended hereby or under the
         Corixa Takeaway Agreement, for use in the entire Cancer Field.

         3.       Amendment of Multi-Field Agreement. The parties hereby agree
that the Multi-Field Agreement is amended as set forth in this Section 3.

                  3.1      Corixa FTE Obligations. The requirement that Corixa
         provide a minimum of [*] FTE's to work on the R&D Programs during the
         Program Term is hereby deleted and replaced by an obligation for Corixa
         to provide that number of FTE's identified in the various letter
         agreements between the parties pursuant to which, among other things,
         the parties agreed to extend the term of certain R&D Programs which are
         listed on Exhibit 2(i) attached hereto and such additional, similar
         letter agreements as the parties may enter into from time to time in
         the future.

                  3.2      Scope of Committee Authority.

                           3.2.1    R&D Programs. For the avoidance of doubt,
                  the Collaboration Steering Committee and the R&D Steering
                  Committee shall have continuing authority in accordance with
                  the terms of the Multi-Field Agreement as amended

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<PAGE>

                  hereby, solely over the R&D Programs which are listed on
                  Exhibit 2(i) attached hereto, and over other such matters
                  under the Multi-Field Agreement as are not, as of the
                  Amendment Date, governed by the terms of the New Agreements.

                           3.2.2    Intellectual Property Matters. Neither the
                  Collaboration Steering Committee nor the R&D Steering
                  Committee shall have any authority over issues relating to:
                  (a) the determination of inventorship or ownership of
                  inventions made by the parties, their directors, officers,
                  employees or agents, whether acting singly or jointly, and
                  arising out of the activities under the Multi-Field Agreement
                  or the New Agreements, or (b) the filing, prosecution,
                  maintenance or defense of patents claiming or covering any
                  such inventions. Authority for such actions shall be governed
                  solely by the Patent Committee established under the amended
                  Article 10 of the Multi-Field Agreement except as otherwise
                  provided in amended Articles 9 and 10 of the Multi-Field
                  Agreement or the New Agreements.

                  3.3      Amendments to Section 5 Entitled "License Grants and
         Other Grants."

                           3.3.1    Diagnostic Rights. Sections 5(d), entitled
                  "Diagnostics," is hereby deleted from the Multi-Field
                  Agreement and shall be of no further force or effect as of the
                  Amendment Date.

                           3.3.2    Rights of First Refusal. The following
                  subsections of Section 5(g), entitled "Certain Rights of First
                  Refusal; Determination of Open Field," are hereby deleted from
                  the Multi-Field Agreement and shall be of no further force and
                  effect: Section 5(g)(i), entitled "After Termination of the
                  Applicable R&D Program," Section 5(g)(iii), entitled
                  "Diagnostic Products," Section 5(g)(iv), entitled "Open Field
                  Determination," and Section 5(g)(v), entitled [*].

                           3.3.3    Antibody Rights. The following subsections
                  of Section 5(b) are hereby amended as indicated below:

                           (i)      Section 5(b)(ii)(A) entitled "Grant" shall
                  be amended to provide that the license grant therein shall
                  include [*], which amendment shall have effect in connection
                  with the letter agreements by and between the parties dated:
                  (i) September 1, 2000, (ii) a further letter agreement dated
                  September 1, 2000, (iii) November 30, 2000, and (iv) April 17,
                  2002.

                           (ii)     Section 5(b)(ii) entitled "Antibody-Based
                  Passive Immunotherapy" and Section 5(e) entitled "Corixa
                  Pre-Clinical and Clinical Development; Ability of Corixa to
                  Request Additional Rights; Ability of GSK to request
                  Additional Formats" are hereby amended so that all matters
                  previously handled by the R&D Steering Committee will from the
                  Amendment Date hereof be handled by the CSC.

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<PAGE>

                           3.3.4    Existing DC Therapy Products. Section
                  5(a)(v) relating to Existing DC Therapy Products is hereby
                  terminated and any reference to that Section in the
                  Multi-Field Agreement has no further effect.

                  3.4      Amendments to Section 6, Entitled "Payments," and
         Section 7, Entitled "Royalties; Sharing of Proceeds."

                           3.4.1    Sublicensee Status. Corixa is hereby deemed
                  not to be a "sublicensee" of GSK for purposes of the
                  Multi-Field Agreement, including without limitation, as such
                  term is used in Section 6, entitled "Payments," and Section 7,
                  entitled "Royalties; Sharing of Proceeds," notwithstanding the
                  licenses granted by GSK to Corixa under the New Agreements.

                           3.4.2    Sharing of Proceeds. Section 7(h) of the
                  Multi-Field Agreement, entitled "Sharing of Proceeds," shall
                  not apply to proceeds received by, or that may become payable
                  to, Corixa in connection with the sublicense, assignment or
                  other conveyance of rights or materials to a third party under
                  the New Agreements which proceeds are shared by Corixa with
                  GSK under the New Agreements except as and to the extent the
                  provisions of such Section 7(h) are incorporated by reference
                  into the Collaboration Agreement.

                  3.5      Limitation of Manufacturing Rights. The rights and
         obligations of the parties under Section 8 of the Multi-Field
         Agreement, entitled "Manufacturing; Supply," including without
         limitation, GSK's right to manufacture certain clinical materials,
         shall not apply to the manufacture, supply or other rights or
         activities relating to materials, components or products developed,
         manufactured and/or supplied under the New Agreements.

                  3.6      Amendment of Section 9, Entitled "Inventions" and
         Section 10, Entitled "patents or patent applications, Prosecution and
         Litigation." Section 9, entitled "Inventions" and Section 10, entitled
         "Patents, Prosecution and Litigation" are hereby amended by deleting
         the text of such sections in their entirety and replacing them with the
         text set forth on Exhibit 3.6 attached hereto.

                  3.7      Amendment of Section 17, Entitled "Term and
         Termination" Section 17, entitled "Term and Termination" is hereby
         amended by deleting the text of Section 17(h) in its entirety and
         replacing it with the text set forth below:

                           "(h)     Subject to Section 18 and any other rights
                  and obligations which survive the termination of this
                  Agreement, SB may terminate this Agreement with respect to
                  certain rights, licenses and obligations of the Parties, on a
                  Field-by-Field basis, as follows: (i) pertaining to the Tb
                  Field, the CT Field and the CP Field, at any time on or after
                  the sixth anniversary of this Agreement by giving [*] prior
                  written notice to Corixa, (ii) pertaining to the Cancer Field,
                  at any time on or after the fourth anniversary of this
                  Agreement by giving [*] prior written notice to Corixa;
                  provided, however, that the rights, licenses and

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<PAGE>

                  obligations of the Parties pertaining to those aspects of the
                  Cancer Field which are governed by the Collaboration
                  Agreement, including without limitation, the right to
                  terminate such rights, licenses and obligations, shall be
                  governed in all respects by the Collaboration Agreement, and
                  no purported termination of such rights, licenses and
                  obligation hereunder shall have any force or effect, and (iii)
                  pertaining to those aspects of the Field(s) which are governed
                  by the Corixa Takeaway Agreement, the rights, licenses and
                  obligations of the Parties shall be governed in all respects
                  by the Corixa Takeaway Agreement, including without
                  limitation, the right to terminate such rights, licenses and
                  obligations, and no purported termination of such rights,
                  licenses and obligation hereunder shall have any force or
                  effect."

                  3.8      Due Diligence. Notwithstanding anything to the
         contrary in the Multi-Field Agreement, if GSK does not advance a Viable
         Clinical Candidate into Clinical R&D from each of the Fields indicated
         below prior to the date indicated, then [*]:

<TABLE>
<CAPTION>
Field                         Deadline for entering Clinical R&D
<S>                           <C>
[*] Field                                    [*]
[*] Field                                    [*]
[*] Field                                    [*]
</TABLE>

         provided that if GSK buys-back the [*] and/or the [*] under the
         Collaboration Agreement it shall be deemed to have complied with its
         due diligence obligations with respect to, as the case may be, the [*]
         Field and/or the [*] Field; and provided further that in case GSK meets
         the any of deadlines above with a Viable Clinical Candidate based on or
         incorporating any [*] transferred to Corixa for validation it shall be
         deemed to have met its due diligence obligation in respect of the
         related [*] and/or [*] Field.

         4.       Acknowledgement; Covenant to Cooperate.

                  4.1      Intent of the parties. The parties hereby acknowledge
         the execution and delivery of the New Agreements. The parties further
         acknowledge that it is their intent to have all of their respective
         rights and obligations relating to the research, development, and
         commercialization of products under the New Agreements be established
         and governed by the terms and conditions set forth in the New
         Agreements and that the Multi-Field Agreement shall have no impact on
         such activities during the term of the New Agreements except as and to
         the extent provisions of the Multi-Field Agreement are incorporated by
         reference into the New Agreements or where the Multi-Field Agreement is
         otherwise identified in the New Agreements as governing a particular
         issue or topic, for example, the management of patent rights.

                  4.2      Resolution of Conflicts, Ambiguities. The parties
         agree to promptly notify each other of any apparent or perceived
         conflict between the Multi-Field Agreement and the New Agreements, or
         either of them, and to negotiate in good faith towards a reconciliation
         of each such apparent or perceived conflict so as to preserve the
         purpose

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<PAGE>

         and goals of the New Agreements, as set forth therein or in Section 4.1
         above, insofar as reasonably possible, being understood that no
         agreement will have precedence over the others.

         5. Confirmation of Terms. Except as amended hereby, the Multi-Field
Agreement shall continue in full force and effect in accordance with its terms.

         6.       Governing Law. This Amendment No. 2 shall be governed by the
laws of the State of Washington, USA.

                  [Remainder of page intentionally left blank.]

<PAGE>

         IN WITNESS WHEREOF, each of the parties has caused this Amendment No. 2
to be executed by its duly authorized officer as of the date first written
above.

CORIXA CORPORATION                                 SMITHKLINE BEECHAM PLC

/s/ STEVEN GILLIS                                  /s/ JEAN STEPHENNE
-----------------------------                      -----------------------------
By:  Steven Gillis                                 By:  Jean Stephenne
Its: President and CEO                             Its: Attorney

<PAGE>

                                                                    EXHIBIT 2(i)

                                  R&D Programs

<TABLE>
<CAPTION>
R&D Program                      Current Expiration Date
<S>                              <C>
 Tb Field                           August 31, 2004
 CP Field                           August 31, 2004
 CT Field                           August 31, 2004
</TABLE>

<PAGE>

                                                                     EXHIBIT 3.6

            TEXT OF SECTION 9 AND SECTION 10 OF MULTI-FIELD AGREEMENT

         9.       INVENTIONS

                  (a)      Inventions. Patentable and non-patentable inventions
or discoveries that arise from the research and development activities conducted
under this Agreement or under either of the New Agreements and that are invented
(i) by an employee or agent of Corixa, solely or jointly other than with an
employee or agent of GSK, shall be owned by Corixa ("Corixa Inventions"); (ii)
jointly by employees or agents of Corixa and GSK shall be jointly owned by
Corixa and GSK and treated as joint inventions under the U.S. laws applicable to
joint inventions (collectively, "Joint Inventions"); and/or (iii) by an employee
or agent of GSK, solely or jointly other than with an employee or agent of
Corixa, shall be owned by GSK ("GSK Inventions"). The determination of
inventorship under this Section 9(a) shall be made in accordance with U.S. laws.

         10.      PATENT MATTERS

                  (a)      Overview. This Section 10 shall govern the
prosecution, maintenance and enforcement of: (a) patents and patent applications
claiming Corixa Inventions, GSK Inventions and Joint Inventions and (b) patents
and patent applications which are subject to any of the licenses granted by
Corixa to GSK, or by GSK to Corixa, under this Agreement or under either of the
New Agreements. For the purposes of this Section 10, such patents and patent
applications shall be collectively referred to as the "Patent Portfolio."

                  (b) Establishment of Patent Committee. The Patent Portfolio
shall be managed, as and to the extent set forth herein, by a patent committee
(the "Patent Committee"). The Patent Committee shall conduct its activities in
good faith and with the goal of maximizing the value of the patents and patent
applications within the Patent Portfolio as if the Patent Portfolio were a
single asset the rights to which were controlled exclusively by the Patent
Committee.

                      (i)      Composition. The Patent Committee shall be
comprised of [*] named representatives of Corixa and [*] named representatives
of GSK. Each of Corixa and GSK will have [*] votes on matters that come before
the Patent Committee. The initial representatives to the Patent Committee are
[*] from Corixa and [*] from GSK. Corixa and GSK may substitute one (1) or more
representatives from time-to-time effective upon written notice to the other
parties. On an alternate basis, one (1) of the representatives of Corixa and one
(1) representative of GSK shall be the chairperson of the Patent Committee, and
in such capacity, such representative shall be responsible for setting the
agenda for the relevant meetings of the Patent Committee, with input from the
other members, and for conducting such meetings of the Patent Committee. The
members of the Patent Committee may invite such other individuals from Corixa or
GSK as they shall determine to be useful and appropriate.

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                      (ii)     Meetings. The Patent Committee shall meet
not less than [*] times per calendar year and at least [*] of those meetings
shall be in person. Subject to the preceding sentence, the Patent Committee
shall meet on such dates and at such times and places as agreed by the members
of the Patent Committee. Each party shall be responsible for all of its own
expenses relating to attendance at or participation in Patent Committee
meetings. Within thirty (30) days following each Patent Committee meeting, the
chairperson shall cause to be prepared and shall provide to the other party a
draft of reasonably detailed written minutes describing all matters reviewed or
considered by the Patent Committee and all determinations or decisions made and
actions taken by the Patent Committee and a summary of the reasons therefor
stated by the members at the meeting. The minutes of any meeting of the Patent
Committee shall be final upon approval by the members of the Patent Committee at
any subsequent meeting. The minutes and the drafts of any minutes shall be the
confidential information of the parties.

                      (iii)    Actions. For the transaction of business, a
quorum consisting of at least [*] of Corixa's members and [*] of GSK's members
must be present at a meeting. Decisions of the Patent Committee, unless
otherwise stated herein, shall be made by majority approval of the members
present at a meeting, provided that a quorum is present.

                      (iv)     Dispute Resolution. A member of the Patent
Committee or a party may raise the issue of whether a decision of the Patent
Committee conforms to the obligations of the Patent Committee, or otherwise
conflicts with the rights and obligations set forth in this Section 10 or any
other section of this Agreement, or either of the New Agreements, or the Patent
Committee may be unable to adopt a decision in accordance with this Agreement
(each a "Patent Dispute"). In the event of a Patent Dispute, the matter in
dispute will be referred back to the Patent Committee for a period of thirty
(30) days for resolution. If a resolution that satisfies all parties is not
reached, the Patent Dispute shall be referred to the Chief Executive Officer of
Corixa and the Senior Vice President, Business Development of GSK for
resolution. Such officers shall be required to discuss a resolution of such
Patent Dispute within thirty (30) days of referral of the Patent Dispute to them
by the Patent Committee. If such officers are unable to resolve the Patent
Dispute, the Patent Dispute shall then be referred to a mutually agreed
experienced external patent attorney for resolution. Said patent attorney will
be charged with resolving the Patent Dispute in a manner consistent with the
obligations of the Patent Committee as if such attorney were acting as the
Patent Committee.

                  (c)      Patent Portfolio Management. Except as provided
herein, the Patent Committee shall have the right and the obligation to
prosecute and maintain the Patent Portfolio and shall do so in a timely manner.
In keeping with Section 10(b), the Patent Committee will use prudent scientific,
business and legal judgment in determining the number and types of patent
applications to be filed pursuant to this Agreement. Notwithstanding the
foregoing, for any patents or patent applications within the Patent Portfolio
that have relevance solely to fields of use that are exclusively controlled by
either Corixa (including without limitation patents that have relevance solely
to the [*] Field) or GSK (such patents or patent applications are "Corixa
Controlled Patents" and "GSK Controlled Patents," respectively), commencing on
the Amendment Date, regarding Corixa Controlled Patents and commencing on the
date GSK [*]

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<PAGE>

whichever is earlier, with the Product claimed by that GSK Controlled Patent,
Corixa or GSK, as applicable, shall have the sole right to prosecute and
maintain such patents or patent applications; provided, however, that each party
will promptly after filing provide to the other party a copy of such patent
applications to the extent such applications could have an impact on such other
party's management of its own patents and patent applications or on the
management of the Patent Portfolio and provided further that costs related
thereto shall be supported by the Corixa and GSK in accordance with Section 10
(d) (iii) below. The Patent Committee shall be charged with identifying those
patents or patent applications that are subject to the control of GSK or Corixa
under the immediately preceding sentence. The Patent Committee will make
reasonable attempts, consistent with its overall responsibility to maximize the
value of the Patent Portfolio as a single asset, to file divisional patent
applications, and to use other methods, to convert patents and patent
applications within the Patent Portfolio into GSK Controlled Patents and Corixa
Controlled Patents. Each party agrees to take reasonable measures to exercise
its right to prosecute and maintain patents or patent applications in the Patent
Portfolio in a manner that will avoid impairing or limiting the value of the
other patents or patent applications in the Patent Portfolio.

                  (d)      Patent Costs.

                           (i)      Cost Allocations. The parties agree that
         third party sublicensees of any rights under the Patent Portfolio will,
         to the extent possible based on good faith negotiations with such third
         party sublicensee(s), be required to bear such portion of the patent
         costs as is reasonable in light of the scope and value of the rights
         they receive. The remaining expenses of maintaining the Patent
         Portfolio (including translation expenses, legal fees, filing costs and
         related expenses) shall be borne in accordance with the following
         Section 10(d)(ii) and Section 10(d)(iii).

                           (ii)     Reimbursement of Costs Prior to Amendment
         Date. GSK shall reimburse Corixa for [*] reasonable and documented
         costs incurred by Corixa prior to the Effective Date in connection with
         the filing, prosecution and maintenance of the Corixa Patents (to the
         extent such costs have not already been reimbursed pursuant to the Tb
         Agreement, the BC Agreement and/or the PC Agreement) and, except as
         provided under Section 10(d)(iii) for the categories of patents and
         patent applications set forth in such Section, for all reasonable and
         documented costs incurred by Corixa during the term of this Agreement
         in connection with the filing, prosecution and maintenance of the
         Corixa Patents and/or the Joint R&D Program Patents up to an amount of
         U.S[*] per year for each individual Field, provided that if Corixa
         incurs less than U.S[*] of such costs during any given year for a
         particular Field, then subject to the last two sentences of this
         Subsection 10(d)(ii), Corixa shall be allowed to apply the remaining
         amount for such Field to costs incurred during such year for any other
         Field(s) to the extent Corixa incurred over U.S[*] of any costs for
         such other Field(s) in such year. Any costs incurred by Corixa in
         connection with the filing, prosecution and maintenance of Corixa
         Patents and/or Joint R&D Program Patents in any particular Field in
         excess of said U.S[*] shall be reimbursed by GSK to Corixa only if they
         have been specifically approved and authorized prior to expenditure by
         the Patent Committee, in its reasonable discretion, and

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<PAGE>

         if they are reasonable and documented. In determining whether to
         approve such additional expenses, the Patent Committee shall apply
         reasonable standards, taking into consideration the norms of the
         biotechnology industry in general.

                           (iii)    Reimbursement of Costs Post Amendment Date.
         GSK and Corixa shall share responsibility for all reasonable and
         documented costs incurred by Corixa after the Amendment Date in
         connection with the filing, prosecution and maintenance of the Patent
         Portfolio (except for costs incurred under Section 10(c)) as set forth
         in this Section 10(d)(iii). The Patent Committee shall classify the
         patents and patent applications within the Patent Portfolio into the
         following categories depending upon the Field for which each such
         patent or patent applications has relevance: (A) [*] Field and [*]
         Field (the "[*] Category"), and (B) the [*] Field and [*] Field (the
         "[*] Category"). Up to [*] in patent filing and maintenance costs shall
         be shared equally by the parties each year during the Term of the
         Collaboration Agreement following the Amendment Date for the [*]
         Category. Amounts in excess of such [*] in the [*] Category shall be
         paid by Corixa and shall be credited against Corixa's obligation to pay
         the Corixa Invested Funds under the Collaboration Agreement. Up to [*]
         in patent filing and maintenance costs shall be paid by GSK each year
         during the Term of the Collaboration Agreement following the Amendment
         Date for the [*] Category. Amounts in excess of such [*] in the [*]
         Category shall be paid by Corixa from its own funds. In the event that
         GSK exercises a "Buy-Back Option," "Proof of Principal Option" or
         "Ninety Percent Option" (as such terms are defined in the Collaboration
         Agreement), GSK shall, upon exercise of each such option, reimburse
         Corixa for costs incurred by Corixa above the [*] cap applicable to the
         [*] Category that qualified for payment from the Corixa Invested Funds,
         in the filing and maintenance of the patents and patent applications
         which are licensed by GSK from Corixa in connection with the exercise
         of each such option.

                           Corixa shall be responsible for the patent costs
         related to the Corixa Controlled Patents. GSK shall be responsible for
         the patent costs related to the GSK Controlled Patents.

                  (e)      Abandonment. In the event Corixa or GSK intends to
finally abandon any patent, any part of a patent, or any patent application
within the Corixa Controlled Patents or GSK Controlled Patents, as applicable,
it shall notify the Patent Committee and the other party shall have the right,
but not the obligation, at its own expense to assume responsibility for such
patent, such part of patent or such patent application, provided that the Patent
Committee agrees that the further prosecution or maintenance of such patent,
part of a patent or patent application will not impair or limit the value of the
other patents or patent applications in the Patent Portfolio.

                  (f)      Claimed Infringement of Third Party Patents. In the
event of the initiation of any suit by a Third Party against Corixa or GSK for
patent infringement involving the manufacture, use, sale, distribution or
marketing of a product, by GSK or by Corixa, that was

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<PAGE>

developed under this Agreement or one of the New Agreements, then the party sued
shall promptly notify the other party in writing. The party controlling the sale
of such product shall have the first right, but not the obligation, to control
the defense of such suit at its own expense. The Patent Committee and both
parties shall assist one another and cooperate in any such litigation at the
request of any of the other party without expense to the requesting party.

                  (g)      Challenges to Patents within the Patent Portfolio.
Except as otherwise provided in this Section 10(g), if a Third Party initiates a
lawsuit, or threatens to do so, challenging the validity of any Patent within
the Patent Portfolio, the Patent Committee shall determine which party shall
control the conduct and defense of such action. In any event, the Patent
Committee and each of the parties shall assist one another and cooperate in any
such litigation at the request of any of the other parties without expense to
the requesting party. Solely in the event that GSK or Corixa is prosecuting and
maintaining patents or patent applications in accordance with Section 10(c)
above, then in the event of any threat or initiation of any legal action by a
Third Party challenging the validity of any Corixa Controlled Patent or GSK
Controlled Patent, as applicable, each of Corixa or GSK, respectively shall
have, at its own expense, the control over such action. If such party elects not
to conduct and defend such action, then the Patent Committee shall be charged
with controlling the conduct and defense of such action. Anything herein to the
contrary notwithstanding, neither GSK nor Corixa shall enter into any settlement
of any Third Party claim that restricts the scope or affects the enforceability
of any patent or patent application within the Patent Portfolio without the
prior written consent of the Patent Committee, which consent shall not be
unreasonably withheld. Corixa and GSK shall assist one another and cooperate in
any such action at the other's request without expense to the requesting party.

                  (h)      Infringement by Third Parties. In the event that a
party becomes aware of actual or threatened infringement of a Patent included
within the Patent Portfolio, that party shall promptly notify the other party in
writing, which other party will promptly communicate the matter to its
representatives on the Patent Committee Except as otherwise provided in this
Section 10(h), the Patent Committee shall determine which party shall have the
first right, but not the obligation, to bring an infringement action against any
Third Party, which party shall also have the right to use the other party's name
in connection therewith. In any event, the Patent Committee and each of the
parties shall assist one another and cooperate in any such litigation at the
request of any of the parties without expense to the requesting party. Solely in
the event that GSK or Corixa is prosecuting and maintaining patents in
accordance with Section 10(c) above, then in the event of any infringement of
such a Corixa Controlled Patent or GSK Controlled Patent, as applicable, Corixa
or GSK, respectively, shall have, at its own expense, the control over such
action. Anything herein to the contrary notwithstanding, neither GSK nor Corixa
shall enter into any settlement of any Third Party claim that restricts the
scope or affects the enforceability of any patent or patent application within
the Patent Portfolio without the prior written consent of the Patent Committee,
which consent shall not be unreasonably withheld. Corixa and GSK shall assist
one another and cooperate in any such action at the other's request without
expense to the requesting party.

                  (i)      Miscellaneous Patent Matters. The parties shall keep
one another informed of the status of their respective activities regarding any
litigation or settlement of a

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dispute concerning any patent or patent application within the Patent Portfolio
or any product claimed thereby.

                  (j)      Expenses and proceeds of litigation. Each party shall
recover its respective actual out-of-pocket expenses, or equitable proportions
thereof, associated with any litigation or settlement contemplated hereby from
any recovery made by that party. The party conducting the litigation shall be
entitled to retain the damages, if any, awarded to it, provided that such party
shall be obligated to pay royalties on such amount of the award as was based on
an approximation of lost sales of a product as if such part of the award were
part of the net sales or other applicable royalty base for such product.

                  (k)      Duration. Section 9 and Section 10 of this Agreement
shall continue in full force and effect until the expiration or termination of
the last license and other rights in favor of the other party, for example,
option rights, rights of first refusal or rights of reversion to any patent or
patent application which is part of the Patent Portfolio, that was granted by
any party to any other party hereunder or under either of the New Agreements.
Upon the expiration or termination of the last license and other rights in favor
of the other party, for example, option rights, rights of first refusal or
rights of reversion pertaining to any particular patent or patent application
within the Patent Portfolio, the owner of such patent or patent application
shall assume full responsibility for the filing, maintenance, enforcement and
defense of such patent or patent application as it shall determine in its sole
discretion and at its own expense.

                  (l)      Disclaimer of Representations and Warranties. NEITHER
PARTY MAKES ANY REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING ANY
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, OTHER THAN
THOSE EXPRESSLY CONTAINED HEREIN OR IN THE NEW AGREEMENTS, INCLUDING WITHOUT
LIMITATION, REPRESENTATIONS OR WARRANTIES RELATING TO: (1) THE PATENTS AND
PATENT APPLICATIONS WITHIN THE PATENT PORTFOLIO, (2) KNOW-HOW OR OTHER
INTELLECTUAL PROPERTY RIGHTS LICENSED HEREUNDER OR UNDER THE NEW AGREEMENTS, (3)
THE ANTIGENS OR OTHER MATERIALS CONVEYED HEREUNDER OR UNDER THE NEW AGREEMENTS,
(4) ANY PRODUCTS DISCOVERED, DEVELOPED AND/OR COMMERCIALIZED HEREUNDER OR UNDER
THE NEW AGREEMENTS.