<PAGE>

                                                                   EXHIBIT 10.2


--------------------------------------------------------------------------------
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.
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                       MANUFACTURING AND SUPPLY AGREEMENT

        This MANUFACTURING AND SUPPLY AGREEMENT (the "Agreement") is entered
into as of October 26, 2001 (the "Signing Date") and made effective as of the
Effective Date (as defined below) between CORIXA CORPORATION, a Delaware
corporation, with its principal place of business at 1124 Columbia Street, Suite
200, Seattle, WA 98104, U.S.A. ("Corixa Corporation"), and AMERSHAM PLC, a
company incorporated under the laws of England, with its principal place of
business at Amersham Place, Little Chalfont, Buckinghamshire, England HP7 9NA
("Amersham"). Both Corixa and Amersham are referred to individually as a "Party"
and collectively as the "Parties."

        WHEREAS, Corixa and Amersham are parties to a development,
commercialization and license agreement of even date herewith wherein Corixa and
Amersham shall develop, and Corixa grants Amersham rights to commercialize,
Bexxar, Corixa's proprietary antibody product, in Europe for the treatment of
humans (the "License Agreement"); and

        WHEREAS, in order to carry out the development and commercialization
goals expressed by the Parties in the License Agreement, Amersham desires to
obtain bulk and finished antibody for products from Corixa and Corixa is willing
to provide such antibody on the terms and conditions hereof; and

        NOW THEREFORE, in consideration of the foregoing premises and the mutual
promises, covenants and conditions contained in this Agreement, the Parties
agree as follows:

        1. DEFINITIONS

        The capitalized terms in this Agreement that are not defined below shall
have the meanings set forth in the License Agreement. The following terms shall
have the following meanings as used in this Agreement:

           1.1 "AMERSHAM IODINE I 131 TOSITUMOMAB" shall mean any Iodine I 131
Tositumomab that Amersham or its agent prepares from Tositumomab.

           1.2 "BI PHARMA AGREEMENTS" shall mean the Supply Agreement between
Coulter and Boehringer Ingelheim Pharma KG dated November 3, 1998 and the
Contract Research and Development Agreement between Coulter and Dr. Karl Thomae
GmbH dated October 22, 1997.

           1.3 "CLINICAL TRIAL" shall mean a trial, conducted by a Party or a
licensee of a Party, in which a Product is administered to humans with the goal
of generating data (a) to support an application for Regulatory Approval of such
Product or (b) for purposes of marketing the Product.

           1.4 "CONTROLLED" means, with respect to any gene, protein, compound,
material, Information or intellectual property right, that the Party owns or has
a license to such gene, protein, compound, material, Information or intellectual
property right and has the ability



                                       1
<PAGE>

to grant to the other Party access, a license or a sublicense (as applicable) to
such gene, protein, compound, material, Information or intellectual property
right on the terms and conditions set forth herein without violating the terms
of any agreement or other arrangements with any Third Party existing at the time
such Party would be first required hereunder to grant the other Party such
access, license or sublicense.

           1.5 "CORIXA" shall mean Corixa Corporation and its Affiliates.

           1.6 "CORIXA INTELLECTUAL PROPERTY RIGHTS" shall mean all Intellectual
Property Rights in existence on the Effective Date that are Controlled by Corixa
during the term of this Agreement, including those Patents set forth in Exhibit
A (which Corixa may update from time to time).

           1.7 "CORIXA IODINE I 131 TOSITUMOMAB" shall mean any Iodine I 131
Tositumomab that Corixa provides to Amersham hereunder.

           1.8 "CORIXA TERRITORY" shall mean all countries and territories of
the world except those in the Territory.

           1.9 "DILIGENT EFFORTS" means the carrying out of obligations or tasks
in a sustained manner consistent with the efforts a Party devotes to a product
or a development or marketing project of similar market potential, profit
potential or strategic value resulting from its own efforts, based on conditions
then prevailing.

           1.10 "EFFECTIVE DATE" shall mean the First Closing Date, as such term
is defined in the Stock Purchase Agreement.

           1.11 "EUROPEAN FACILITY" shall have the meaning set forth in Section
3.3(a).

           1.12 "FULLY ALLOCATED COST" shall mean the direct and indirect costs
of Tositumomab provided by Corixa to Amersham or Corixa Iodine I 131 Tositumomab
and shall be computed in accordance with United States generally accepted
accounting principles, consistently applied. To the extent that any such costs
arise from activities performed for Amersham as well as other Corixa partners
for the Product, the amounts allocated to Amersham shall be a fair, pro rata
allocation based upon the performance for Amersham relative to the performance
for other Corixa partners for the Product. Fully Allocated Cost shall include
without limitation:

                (a) cost and expenses incurred by Corixa, including, but not
limited to, payments owed by [*], for the manufacture or supply to Amersham of
such Tositumomab or Corixa Iodine I 131 Tositumomab, including, but not limited
to, the [*] for such antibody, [*] payments (limited to [*]), payments related
to [*] (to the extent not otherwise [*] pursuant to this Agreement), [*]
payments, and [*] owed to such Third Parties, plus



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                (b) [*] Costs, plus

                (c) If applicable, the cost of forward foreign currency
contracts to protect against risk of changes in foreign exchange rates, provided
that such costs are approved in advance by the Parties, plus

                (d) Corixa's internal and external expenses, including
out-of-pocket expenses and employee expenses, if any, with respect to [*]
associated with [*] Tositumomab or Corixa Iodine I 131 Tositumomab [*], plus

                (e) The cost of [*] in Tositumomab or Corixa Iodine I 131
Tositumomab [*] activities, including, without limitation, [*], plus

                (f) A reasonable allocation, with respect to such Tositumomab or
Corixa Iodine I 131 Tositumomab, of Corixa's: (i) [*] (to the extent not
previously included in (d) or (e)), (ii) [*] costs, and (iii) [*] costs
including [*]. Such allocations shall be in accordance with reasonable cost
accounting methods, consistently applied, of Corixa.

        1.13 "GOOD CLINICAL PRACTICE" or "GCP" shall mean the then current
standards for clinical trials for pharmaceuticals, as set forth in (i) the rules
and regulations of the International Conference on Harmonization, and (ii) any
other applicable requirements for clinical trial activities under the laws,
rules or regulations of the Territory.

        1.14 "GOOD LABORATORY PRACTICE" or "GLP" shall mean the then current
standards for laboratory activities for pharmaceuticals, as set forth in the
FD&C Act and applicable regulations and guidances promulgated thereunder,
including without limitation the Code of Federal Regulations, as amended from
time to time, and any other applicable requirements for laboratory activities
under the laws, rules or regulations of the Territory.

        1.15 "GOOD MANUFACTURING PRACTICE" or "GMP" shall mean the current
standards for the manufacture of pharmaceuticals, as set forth in the FD&C Act
and applicable regulations and guidances promulgated thereunder, including
without limitation the Code of Federal Regulations, as amended from time to
time, and any other applicable manufacturing requirements under the laws, rules
or regulations of the Territory.

        1.16 "INFORMATION" means information, results and data of any type
whatsoever, in any tangible or intangible form whatsoever, including without
limitation, databases, inventions, practices, methods, techniques,
specifications, formulations, formulae, knowledge, know-how, skill, experience,
test data including pharmacological, biological, chemical, biochemical,
toxicological and clinical test data, analytical and quality control data,
stability data, studies and procedures, and patent and other legal information
or descriptions.

        1.17 "INITIAL APPROVAL CLINICAL TRIALS" shall have the meaning set forth
in the License Agreement.


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        1.18 "INITIAL DEVELOPMENT PLAN" shall have the meaning set forth in the
License Agreement.

        1.19 "INTELLECTUAL PROPERTY RIGHTS" shall mean all Patents, copyrights,
regulatory filings, Know-How, or any other intellectual property other than
trademarks, that are Controlled during the term of this Agreement by a Party or
jointly by the Parties and that relate to the development, manufacture,
importing, use, marketing and/or sale of the Product. The term "Intellectual
Property Rights" shall include any rights obtained by either Party from a Third
Party, subject to the terms and conditions of the agreements in which such
rights were conferred. The term "Intellectual Property Rights," however, shall
not include Patents, copyrights, regulatory filings, know-how and/or trade
secrets, or any other intellectual property of either Party for the [*] or [*]
of [*], whether developed prior to or after the Effective Date.

        1.20 "INVENTION" means any invention, development, result, Know-How or
other Information, and all intellectual property relating thereto, made,
discovered or developed (i) solely by a Party and its employees or agents
pursuant to work performed under the Agreement or (ii) jointly by the Parties
and their employees or agents pursuant to work performed under the Agreement.

        1.21 "IODINE I 131 TOSITUMOMAB" shall mean any therapeutic, prophylactic
or palliative product [*] or [*] the [*] of [*] conjugated with 131Iodine that
was one of the active agents tested in Corixa's clinical trial with Protocol No.
RIT-II-004 as referred to in that Protocol as [*] anti CD20 murine monoclonal
antibody.

        1.22 "JOINT OTHER INVENTIONS" means any and all Other Inventions made
jointly by employees or agents of both Parties pursuant to work conducted under
the Agreement.

        1.23 "KNOW-HOW" shall mean any technical information that is secret and
identified.

        1.24 "NET SALES" shall mean gross amounts invoiced for sales of the
Product in the Territory by either Party, its Affiliates or sublicensees, as
appropriate, to Third Parties, less the following items: (i) trade, quantity and
cash discounts or rebates actually allowed and taken and any other adjustments,
including, without limitation, those granted on account of [*]; (ii) credits,
rebates, charge-back and prime vendor rebates, fees, reimbursements or similar
payments granted or given to [*] and other [*]; (iii) any tax, tariff, customs
duties, excise or other duties or other governmental charge (other than an
income tax) levied on the sale, transportation or delivery of a Product and
borne by the seller thereof; (iv) payments or rebates paid in connection with
sales of Products to any governmental or regulatory authority in respect of any
medical insurance funded by a state or federal government; and (v) any charge
for freight, insurance or other transportation costs charged to the customer.
For clarity, Net Sales shall not include: sales of the Product by and between a
Party and its Affiliates (except where such Affiliates are end users).


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<PAGE>

        1.25 "NORDION AGREEMENTS" shall mean (a) the Supply Agreement between
Coulter Pharmaceutical, Inc. and MDS Nordion Inc. dated August 31, 1998; (b) the
Supply Agreement for I-131 between Coulter Pharmaceutical, Inc. and MDS Nordion,
Inc. dated September 13, 2000; (c) the Development Agreement between Coulter
Pharmaceutical, Inc. and MDS Nordion, Inc. dated November 13, 1995; and (d) the
Facilities Agreement between Coulter Pharmaceutical, Inc. and MDS Nordion, Inc.
dated August 31, 1998.

        1.26 "OTHER INVENTION" means any Invention that is not a Product
Invention.

        1.27 "PATENT" means (i) unexpired letters patent (including inventor's
certificates) that have not been held invalid or unenforceable by a court of
competent jurisdiction from which no appeal can be taken or has been taken
within the required time period, including without limitation any substitution,
extension, registration, confirmation, reissue, re-examination, renewal or any
like filing thereof and (ii) pending applications for letters patent, including
without limitation any continuation, division or continuation-in-part thereof
and any provisional applications.

        1.28 "PRODUCT" shall mean (a) Iodine I 131 Tositumomab as defined in
Section 1.21 or (b) any therapeutic, prophylactic or palliative product
containing or comprising Tositumomab as defined in Section 1.37 for use in
connection with a Iodine I 131 Tositumomab, in any formulation or mode of
administration.

        1.29 "PRODUCT INVENTION" means any Invention that pertains [*] to or the
[*] use of which is [*] to, the Product or its development, manufacture or use.

        1.30 "QA/QC COSTS" shall mean Corixa's internal and external costs of
quality assurance and quality control work performed by or on behalf of Corixa
related to Product [*] of Tositumomab and Corixa Iodine I 131 Tositumomab, but
only to the extent that such quality assurance and quality control work is [*].
QA/QC Costs shall include a reasonable allocation of Corixa's [*], and shall
include any allocation of the costs of [*] or any costs of [*] related to
Tositumomab.

        1.31 "SOLE OTHER INVENTIONS" means any and all Other Inventions made,
discovered or developed solely by a Party and its employees or agents pursuant
to work performed under the Agreement.

        1.32 "SPECIFICATIONS" shall mean the requirements and standards
pertaining to Tositumomab or Iodine I 131 Tositumomab (depending upon context)
and consistent with filings made for Regulatory Approval and all relevant
written agreements between Corixa and a Third Party with respect to manufacture
or supply of Tositumomab, Iodine I 131 Tositumomab or Product, which
specifications are set forth in the BLA identified by Biologics License
Application Submission Tracking Number 125011, provided that such specifications
may be modified in writing by the Parties from time to time as follows: any
modifications to the Specifications shall be reasonably acceptable to both
Parties or required for approval of the

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Product in the Territory and shall be reasonably consistent with respect to [*].
The Specifications shall be release or stability specifications, as applicable,
and each reference to Specifications shall mean the type of such Specifications
appropriate to the context.

           1.33 "STOCK PURCHASE AGREEMENT" shall mean that certain Stock
Purchase Agreement entered into between Corixa Corporation and Nycomed, Inc. as
of the Signing Date.

           1.34 "TERRITORY" shall mean the countries and territories of Europe
set forth on Exhibit B of the License Agreement.

           1.35 "THERAPY" shall mean two doses of Tositumomab and two doses of
Corixa Iodine I 131 Tositumomab (one for dosimetric purposes and one for
therapeutic purposes, including "top-off" vials) for administration to a single
patient, unless otherwise adjusted by mutual agreement of the Parties.

           1.36 "THIRD PARTY" means any entity other than (i) Corixa, (ii)
Amersham or (iii) an Affiliate of either of them.

           1.37 "TOSITUMOMAB" shall mean the [*] that (i) has not been
conjugated with 131 Iodine or any other [*] and (ii) was administered to
patients in Corixa's clinical trial with Protocol No. RIT-II-004 as referred to
in that Protocol as [*] anti CD20 murine monoclonal antibody. Except as
otherwise specified in this Agreement, Tositumomab shall mean both bulk and
filled material.

           1.38 "TRANSFER PRICE" shall have the meaning set forth in Section
4.1(a).

        2. GENERAL UNDERSTANDING. Pursuant to the BI Pharma Agreements and the
Nordion Agreements, Corixa has the ability to have Tositumomab and Corixa Iodine
I 131 Tositumomab manufactured and supplied to it and its licensees. Under this
Agreement, Corixa will provide certain amounts of Tositumomab and Corixa Iodine
I 131 Tositumomab for use in the Initial Approval Clinical Trials and to
Amersham for Amersham's use in the Territory in accordance with the License
Agreement. Amersham acknowledges and understands that Corixa's ability to supply
Tositumomab and Corixa Iodine I 131 Tositumomab to Amersham under this Agreement
is limited by the BI Pharma Agreements, the Nordion Agreements and Corixa's
agreements with other suppliers and other licensees, including Glaxo SmithKline.
Amersham hereby agrees to be legally bound by and to comply with all applicable
(as a result of this Agreement) provisions of the BI Pharma Agreements and the
Nordion Agreements. Corixa shall consult with Amersham before entering into a
new supply agreement during the term of this Agreement to replace or supplement
the BI Pharma Agreements.


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<PAGE>

        3. MANUFACTURING AND SUPPLY OF ANTIBODY.

           3.1 TOSITUMOMAB.

               (a) OVERVIEW. Except as set forth in Sections 3.1(e) and 3.11,
and subject to availability of Tositumomab and Amersham's compliance with the
terms and conditions of this Agreement and the License Agreement, Corixa shall
use commercially reasonable efforts to have manufactured and supply to Amersham
all of its requirements in the Territory for Tositumomab in accordance with the
BI Pharma Agreements and the volume allocation methodology set forth in Section
3.11. Amersham shall pay for such Tositumomab as set forth in Article 4. Except
as set forth in Section 3.1(e), Amersham shall obtain from Corixa all of
Amersham's requirements for Tositumomab in the Territory, whether for
development or commercial sale.

               (b) FORECASTS AND ORDERING.

                   (i) Corixa has already submitted to BI Pharma the forecast
shown in Exhibit A for the supply of Tositumomab to Amersham, including the
supply of Tositumomab designated for use in an Initial Approval Clinical Trial,
for the period from the Effective Date until December 31, 2003 (the "Corixa
Forecast"). Within thirty (30) days after the approval by the JDC of the Initial
Development Plan, and no later than the [*] of the [*] of each calendar quarter
thereafter, Amersham shall furnish to Corixa a written rolling [*] forecast of
its anticipated purchase of bulk Product (including Tositumomab to be used in
the manufacture of Corixa Iodine I 131 Tositumomab or Amersham Iodine I 131
Tositumomab) or filled and finished Product for the Territory which shall be
consistent with the terms and conditions of the BI Pharma Agreements (the
"Amersham Forecast"). Each Amersham Forecast shall cover a [*] forecast period
starting [*] after the quarter in which Amersham provided such Amersham Forecast
to Corixa. The Amersham Forecast shall be submitted to Corixa in the format
specified in writing by Corixa. Unless the JDC agrees otherwise, Amersham shall
include in the Amersham Forecasts and shall specifically identify within the
Amersham Forecasts, those quantities of Tositumomab intended for use in an
Initial Approval Clinical Trial in the Territory, as decided by the JDC or
Corixa pursuant to Section 4.6 of the License Agreement.

               (ii) Subject to subsection (iii) below, Amersham shall be
obligated to purchase from Corixa those portions of the Amersham Forecasts that
are binding in accordance with the criteria set forth in Appendix 2B of the BI
Pharma Agreement. Amersham shall pay Corixa, in accordance with the terms of
Article 4 of this Agreement, for all such quantities of Tositumomab.

               (iii) Corixa shall be obligated, for the period from the
Effective Date until the end of an Initial Approval Clinical Trial, to pay for
all Tositumomab designated for use in an Initial Approval Clinical Trial in the
Territory, to the extent that such Tositumomab is manufactured pursuant to a
binding portion of the Corixa Forecast or an Amersham Forecast.


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All amounts paid by Corixa pursuant to this subsection 3.1(b)(iii) shall be
included in the Development Budget for the Initial Approval Clinical Trials and
shall be Initial Approval Trials Costs for the Initial Approval Clinical Trials
and subject to the terms and conditions of the License Agreement, including but
not limited to Section 5.2(a)(iii) thereof.

                   (iv) In the event that Corixa is informed by BI Pharma that
BI Pharma, pursuant to Section 3.1.2 of the BI Pharma supply agreement, will not
be able to supply enough Tositumomab to satisfy Amersham's projected
requirements for Tositumomab during a particular period, Corixa shall inform
Amersham of such projected shortfall and Section 3.1(e) shall apply.

               (c) DELIVERY; SHIPMENT; TITLE. It is anticipated that BI Pharma
will manufacture Tositumomab twice a year. Tositumomab will be delivered to
Amersham FOB at the manufacturing facility of BI Pharma or an alternate Corixa
supplier. "FOB" shall be construed in accordance with INCOTERMS 2000 of the
International Chamber of Commerce. Amersham shall be the importer of record for
all Tositumomab delivered hereunder. Title to individual shipments of
Tositumomab that are not designated for use in an Initial Approval Clinical
Trial shall pass to Amersham upon Amersham's payment of that portion of the
Transfer Price set forth in Section 4.1(a)(i). Amersham shall bear the
responsibility for all expenses related to the delivery of Tositumomab from BI
Pharma to Amersham's storage facility.

               (d) VIAL LABELING; STORAGE. Amersham shall vial label, store and
distribute Tositumomab in accordance with (i) Corixa's and BI Pharma's
Specifications for vial labeling and storage and (ii) all applicable laws, rules
and regulations. It shall be Amersham's sole responsibility to establish and
maintain a site for such activities. Distribution of Tositumomab hereunder shall
be in accordance with Section 3.4.

               (e) CORIXA INABILITY TO SUPPLY. If Corixa is unable to supply any
Tositumomab to Amersham due to BI Pharma's inability to supply as set forth in
Section 3.1.2 of the BI Pharma Agreement, Corixa shall have the right to
establish a second source of Tositumomab and Amersham shall remain obligated to
obtain all Tositumomab from Corixa. If by [*] days after the date of the most
recent delivery of Tositumomab to Amersham, Corixa has not established a second
source, then Corixa shall provide Amersham with a written description of its
plan to establish such a second source within the next [*] days. If Corixa does
not successfully establish a second source of Tositumomab within [*] days
following the date of the most recent delivery of Tositumomab to Amersham, then
Corixa shall grant to Amersham the license set forth in Section 2.1(c) of the
License Agreement and Amersham will thereafter have the right to supply such
antibody itself at its expense.

           3.2 CORIXA IODINE I 131 TOSITUMOMAB.

               (a) OVERVIEW. Except as set forth in Section 3.11 and subject to
Amersham's compliance with the terms and conditions of this Agreement, Corixa
shall use [*] efforts to provide Corixa Iodine I 131 Tositumomab to Amersham
until the earlier of: (i) the first


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<PAGE>

date that Amersham is able to manufacture Amersham Iodine I 131 Tositumomab in
sufficient quantities to fulfill its requirements for Iodine I 131 Tositumomab,
(ii) December 31, [*], or (iii) Nordion's last date of production in [*] for
Corixa Iodine I 131 Tositumomab. In no event will Corixa be obligated to supply
Corixa Iodine I 131 Tositumomab to Amersham after December 31, [*]. Corixa will
supply Corixa Iodine I 131 Tositumomab to Amersham in accordance with the
Nordion Agreements and the volume allocation methodology set forth in Section
3.11. Amersham acknowledges that such supply may be subject to delays or
interruptions due to suspended production during periods of Nordion's scheduled
maintenance of its facilities in accordance with Section 5.3 of the Nordion
Supply Agreement dated August 31, 1998. Amersham shall pay for Corixa Iodine I
131 Tositumomab as set forth in Article 4.

               (b) ANTICIPATED NUMBER OF THERAPIES. Corixa anticipates being
able to provide the number of Therapies set forth below in the Territory in the
specified calendar years:

<TABLE>
<CAPTION>
           Calendar Year             Maximum Number of Therapies
           -------------             ---------------------------
<S>                                            <C>
               2001                             [*]
               2002                             [*]
               2003                             [*]
</TABLE>

        The foregoing estimates are based on assumptions that: (i) the demand
for Corixa Iodine I 131 Tositumomab in the Territory will be spread evenly
throughout each calendar year and (ii) [*]. Amersham acknowledges that if one or
both of these assumptions is not correct, then Corixa's ability to provide the
anticipated number of Therapies will be adversely affected and the number of
available Therapies will be adjusted accordingly.

        If Corixa becomes able to supply more than the specified number of
Therapies in calendar year 2001, 2002 or 2003, then the Parties will mutually
agree whether Corixa will provide additional Therapies in the Territory.
Notwithstanding the foregoing, Amersham acknowledges and agrees that Corixa may
be unable to meet the anticipated Therapy requirement for the Territory for a
specified week or a specified year even if the amounts of Corixa I 131
Tositumomab ordered by Amersham are in weekly amounts balanced over the
applicable calendar year.

               (c) FORECASTS AND ORDERING.

                   (i) Within thirty (30) days after the approval of the Initial
Development Plan, Amersham shall provide Corixa with its projected requirements
for Corixa Iodine I 131 Tositumomab through December 31, [*] in accordance with
the Amersham Forecast mechanism set forth in Section 3.1(b). Unless the JDC
agrees otherwise, Amersham shall include in all of its forecasts and firm orders
and specifically identify within such forecasts and firm orders, those
quantities of Corixa Iodine I 131 Tositumomab intended for use in an Initial
Approval Clinical Trial in the Territory, as decided by the JDC or Corixa
pursuant to Section 4.6 of the License Agreement. Amersham shall update such
forecast for its entire projected


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requirements of Corixa Iodine I 131 Tositumomab quarterly. Such forecasts shall
be consistent with the quantities of Corixa I 131 Tositumomab set forth in
Section 3.2(b).

                   (ii) On the Effective Date and on the first day of each month
thereafter, Amersham will submit a rolling [*] forecast to Corixa for Corixa I
131 Tositumomab in the Territory (the "Corixa I 131 Tositumomab Forecast"). The
Corixa I 131 Tositumomab Forecast shall be consistent with (A) the forecasting
and ordering mechanisms required under the Nordion Agreements and (B) the
quantities of Corixa I 131 Tositumomab set forth in Section 3.2(b). Each Corixa
I 131 Tositumomab Forecast shall cover, in weekly amounts, the [*] that follow
the month in which such forecast was submitted to Corixa.

                   (iii) Every Monday during the period that Corixa is supplying
Corixa Iodine I 131 Tositumomab to Amersham, Amersham shall place a firm order
for all Corixa Iodine I 131 Tositumomab that it wishes to receive, including for
so long as applicable the Corixa Iodine I 131 Tositumomab designated for use in
an Initial Approval Clinical Trial, during the week that is two weeks after the
week of such firm order. Such firm order shall be consistent with the quantities
of Corixa I 131 Tositumomab set forth in Section 3.2(b) and shall be considered
binding on Amersham. Subject to the next sentence, Amersham shall pay for all
Corixa Iodine I 131 Tositumomab delivered pursuant to such a firm order in
accordance with Article 4. Corixa shall pay for all Corixa Iodine I 131
Tositumomab delivered pursuant to such a firm order that is designated in such
firm order for use in an Initial Approval Clinical Trial in the Territory. Any
shortfalls of Corixa I 131 Tositumomab shall be handled as set forth in Section
3.11.

               (d) DELIVERY; SHIPMENT. The Corixa Iodine I 131 Tositumomab will
be delivered to Amersham FOB Nordion's facility. "FOB" shall be construed in
accordance with INCOTERMS 2000 of the International Chamber of Commerce.
Amersham shall be the importer of record for all Corixa Iodine I 131 Tositumomab
delivered hereunder. Title to individual shipments of Corixa Iodine I 131
Tositumomab that are not designated for use in an Initial Approval Clinical
Trial shall pass to Amersham upon Amersham's payment of that portion of the
Transfer Price set forth in Section 4.1(a)(i). Subject to the next sentence,
Amersham shall also bear the responsibility for all expenses related to the
delivery of Amersham's portion of Tositumomab to Nordion's facility (which will
be coordinated by Corixa) and the subsequent delivery of Corixa Iodine I 131
Tositumomab from Nordion's facility to Initial Approval Clinical Trial sites,
Subsequent Clinical Trial sites and Amersham's customers in the Territory.
Corixa shall bear the foregoing costs for all Corixa Iodine I 131 Tositumomab
that is designated for use in an Initial Approval Clinical Trial. Distribution
of Corixa Iodine I 131 Tositumomab for use in an Initial Approval Clinical Trial
shall be in accordance with Section 3.4.

               (e) INITIAL APPROVAL TRIAL COSTS. All amounts paid by Corixa
pursuant to subsection 3.1(c) and 3.2(d) shall be included in the Development
Budget for the Initial Approval Clinical Trials and shall be Initial Approval
Trials Costs for the Initial Approval


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Clinical Trials and subject to the terms and conditions of the License
Agreement, including but not limited to Section 5.2(a)(iii) thereof.

           3.3 AMERSHAM IODINE I 131 TOSITUMOMAB.

               (a) No later than December 31, [*] or the later date agreed in
writing by the Parties ([*]), Amersham shall establish a radiolabeling facility
that, in accordance with all applicable laws and regulations, converts
Tositumomab to Amersham Iodine I 131 Tositumomab and supplies all of Amersham's
requirements for Iodine I 131 Tositumomab for development and commercial sale in
the Territory (the "European Facility"). Amersham may begin supplying Amersham
Iodine I 131 Tositumomab at any time prior to December 31, [*] or such agreed
date.

               (b) Within [*] days after the Effective Date, Amersham shall
provide Corixa with a timetable for the establishment of the European Facility
and a copy of Amersham's full plan (rather than a summary thereof) for the
manufacture of Amersham Iodine I 131 Tositumomab, which plan shall include the
milestones and timelines set forth on Exhibit B hereto. Amersham shall update
such timetable and plan semi-annually, provided that any updates or
modifications to the milestones and timelines set forth on Exhibit B shall
require Corixa's prior written consent. Corixa may comment on the initial and
updated timetables and plans. Amersham's failure to provide the first timetable
and the first plan within [*] days after the Effective Date shall constitute a
material breach of this Agreement. Amersham shall be responsible for all capital
and other expenses related to the establishment of the European Facility and its
operation.

               (c) At the request of Amersham, during the period commencing on
the Effective Date and ending [*] years after the date determined in accordance
with Section 3.3(a), Corixa shall provide reasonable assistance, within Corixa's
area of expertise, to help Amersham establish and operate the European Facility.
Provision of such assistance shall include, but not be limited to, supply of any
Corixa know-how which Amersham may require to the extent such Corixa know-how
can be provided to Amersham under applicable agreements with Third Parties. In
the event that Amersham requests that Corixa perform work, including providing
consultation services, under this Section 3.3(c), Amersham shall reimburse
Corixa for all out-of-pocket expenses and personnel expenses (at the applicable
FTE Rate) incurred by Corixa with respect to such performance within [*] days of
receipt of an invoice from Corixa.

               (d) In the event that based on Amersham's progress against the
milestones and timelines set forth on Exhibit B (as may be amended in accordance
with Section 3.3(b)), Corixa makes a good faith determination that the European
Facility is not reasonably likely to be completed and available to manufacture
and supply Amersham's requirements of Iodine I 131 Tositumomab for development
and commercial sale in the Territory by the later of December 31, [*] or the
date agreed in writing pursuant to Section 3.3(a), Corixa may give notice to
Amersham that Corixa intends to (i) terminate this Agreement and the License
Agreement or (ii) adjust the licenses granted by Corixa under the License
Agreement to become non-exclusive. Amersham hereby acknowledges that if Corixa
proceeds under subsection (ii),


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(1) the License Agreement shall otherwise remain in full force and effect in
accordance with its terms, including, but not limited to, all payment terms, and
(2) Corixa shall retain the right to terminate this Agreement pursuant to
Section 7.2 on account of Amersham's material breach of this Agreement,
including (without limitation) the obligations set forth in Sections 3.3(a) and
3.3(b).

               (e) Delivery of Tositumomab to the European Facility for
radiolabeling will be the responsibility of Amersham. Amersham shall be
responsible for all shipping, manufacturing and supply expenses associated with
the conversion of Tositumomab to Amersham Iodine I 131 Tositumomab.

               (f) Amersham shall establish and maintain a site for the vial
labeling, storage, allocating and distribution of Amersham Iodine I 131
Tositumomab in accordance with Corixa's and BI Pharma's Specifications and
applicable legal and regulatory requirements in the Territory for vial labeling
and storage.

               (g) At the request of Corixa, Amersham shall negotiate in good
faith a supply agreement with Corixa pursuant to which Amersham would supply
Amersham Iodine I 131 Tositumomab to Corixa for development or commercialization
in the Corixa Territory.

           3.4 DISTRIBUTION. Distribution of Tositumomab, Iodine I 131
Tositumomab and Product in the Territory shall be handled exclusively by
Amersham and shall be in accordance with applicable law and regulations,
including regulations promulgated by nuclear regulatory agencies. Except as set
forth below, the expenses related to such distribution shall be solely the
responsibility of Amersham. Notwithstanding the foregoing, Corixa may elect to
itself or through a Third Party designee distribute some or all of the
Tositumomab, Iodine I 131 Tositumomab and Product in the Territory in connection
with an Initial Approval Clinical Trial. Corixa, or Amersham at Corixa's
request, shall coordinate product release, customs clearance and delivery of
Tositumomab, Iodine I 131 Tositumomab and Product to Initial Approval Clinical
Trial sites in the Territory. Amersham shall coordinate product release, customs
clearance and delivery of Tositumomab, Iodine I 131 Tositumomab and Product to
all Subsequent Clinical Trial sites and customer sites in the Territory. All
expenses related to the distribution of the Tositumomab, Iodine I 131
Tositumomab and Product designated for use in the Initial Approval Clinical
Trials shall be solely the responsibility of Corixa. All amounts paid by Corixa
pursuant to this Section 3.4 shall be included in the Development Budget for the
Initial Approval Clinical Trials and shall be Initial Approval Trials Costs for
the Initial Approval Clinical Trials and subject to the terms and conditions of
the License Agreement, including but not limited to Section 5.2(a)(iii) thereof.

           3.5 CUSTOMER ORDERS. Amersham shall establish and maintain
infrastructure to collect and collate customer orders for Tositumomab or Iodine
I 131 Tositumomab and Product and to transfer information regarding such
customer orders to Corixa's order fulfillment system.

           3.6 ENHANCEMENTS. Upon mutual agreement of the Parties to effect one
or more Product enhancements in the manufacturing process (including without
limitation the [*] at



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<PAGE>

BI Pharma and [*] Iodine-131), the Parties shall cooperate to effect such
enhancements. Amersham shall bear all expenses (including, without limitation,
the cost of any studies, Clinical Trials and changes in Product manufacturing)
for enhancements that are only applicable to the Territory. Amersham shall bear
[*] percent ([*]%) of all world-wide expenses (including, without limitation,
the cost of any studies, Clinical Trials and changes in Product manufacturing)
for enhancements that are applicable throughout the world, provided Amersham has
access to such enhancements and has agreed to participate in such enhancement
process. Each Party (the "Auditing Party") shall have the right, upon prior
written notice to the other Party (the "Audited Party") and at the Auditing
Party's cost, to have the certified public accountants of the Auditing Party's
choice, bound by confidentiality and reasonably acceptable to the Audited Party,
audit Audited Party's books and records to verify the Audited Party's
calculations of expenses for enhancements for which the Auditing Party is
obligated to pay a percentage of the world-wide expenses therefor. Each Party
may exercise this right no more than once per contract year. If Amersham elects
not to participate in the development of a particular Product enhancement, then
in the event that such Product enhancement would otherwise reduce the Fully
Allocated Cost, Amersham nonetheless shall pay [*] that does [*] such a [*].

           3.7 MANUFACTURING REGULATORY COMPLIANCE. Any manufacture of
Tositumomab and Iodine I 131 Tositumomab for development purposes or commercial
sale in the Territory shall be performed in full compliance with GCP, GLP and
GMP and all applicable United States laws and regulations (including regulations
promulgated by the Nuclear Regulatory Commission or any successor thereto).
Amersham will notify Corixa of any regulatory requirements for manufacture of
Tositumomab and/or Iodine I 131 Tositumomab for sale in the Territory with which
it wishes Third Party manufacturers of Tositumomab and/or Corixa Iodine I 131
Tositumomab to comply. To the extent Corixa can cause such manufacturers to
comply with such regulatory requirements, Corixa will do so. To the extent
permitted by applicable laws, Amersham or its designee shall serve as the point
of contact with the foreign equivalents of the FDA in the Territory and any
other applicable governmental entity in the Territory concerning the manufacture
and supply of Tositumomab and Iodine I 131 Tositumomab, but may, as appropriate,
request the assistance of Corixa with respect to communications with such
governmental entities. Amersham shall reimburse Corixa for all out-of-pocket and
FTE expenses incurred in connection with providing such assistance.

           3.8 REGULATORY COMPLIANCE. Amersham shall be responsible for
establishing and maintaining infrastructure to ensure that Tositumomab or Iodine
I 131 Tositumomab and Product comply with applicable drug regulations in the
Territory.

           3.9 QUALITY CONTROL; TESTING. Any Party responsible for the
manufacture of Tositumomab or Iodine I 131 Tositumomab shall maintain a quality
control and testing program consistent with GMP, as required by the FDA and/or
any other governmental entity whether in the United States or part of another
applicable foreign jurisdiction, with respect to the manufacture by or on behalf
of either Party hereunder; provided that regarding such requirements in the
Territory, Corixa shall be obligated to comply only with requirements of the EU
itself and not of individual countries or territories within the Territory to
the extent such


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<PAGE>

requirements may differ from those of the EU. Corixa shall be entitled to audit
the quality control program for the manufacture of Tositumomab and Iodine I 131
Tositumomab that is manufactured by Amersham. Each Party shall bear its own
expenses for such audits.

           3.10 NON-COMPLIANCE WITH SPECIFICATIONS. Corixa shall provide to
Amersham copies of all analysis certificates and data that Corixa receives from
the Third Party manufacturer with respect to Tositumomab or Corixa Iodine I 131
Tositumomab ordered by Amersham hereunder. In the event that Amersham wishes to
avail itself of the defective product procedures set forth in Section 5.9 of the
BI Pharma Agreement or Section 6.4 of the Nordion Supply Agreement dated August
31, 1998, it shall provide all relevant information to Corixa, in the case of
Tositumomab, not more than [*] days after receipt of shipment by Amersham, and,
in the case of Corixa I 131 Tositumomab, not more than [*] days after receipt of
shipment of Amersham. Corixa shall use [*] efforts to perform the relevant
activity in accordance with Section 5.9 of the BI Pharma Agreement or Section
6.4 of the Nordion Supply Agreement dated August 31, 1998, as applicable. The
Parties shall work together, at the [*] expense of [*], to use [*] efforts to
enable Amersham to avail itself of such procedures.

           3.11 ALLOCATION IN THE EVENT OF PRODUCT SHORTAGES.

               (a) ALLOCATION OF IODINE I 131 TOSITUMOMAB. In the event of
shortages in a batch of Iodine I 131 Tositumomab such that either (i) Corixa is
unable to supply to Amersham from such batch the amount of Corixa Iodine I 131
Tositumomab estimated to be supplied by Corixa to Amersham per batch in
accordance with Section 3.2(b), or (ii) there is insufficient material to supply
to Corixa from such batch Corixa's pending order for Iodine I 131 Tositumomab
for use in the Corixa Territory, then any Iodine I 131 Tositumomab material
produced by Nordion, Kanata, from the facility in existence as of the Effective
Date, shall be allocated as follows: [*] percent ([*]%) of the manufactured
vials in each batch shall be allocated to the Territory and [*] percent ([*]%)
of the manufactured vials in each batch shall be allocated for use by Corixa in
the Corixa Territory (rounded to the nearest whole vial on weekly basis). If
after the Effective Date, Corixa, alone or together with one or more of Corixa's
partners in the Corixa Territory, funds further expansion [*] for production of
Iodine I 131 Tositumomab, this expanded capacity shall not be available to
Amersham unless Amersham funds an appropriate part of the costs of the
additional capacity. If such funding is provided by Amersham, apportionment of
available Iodine I 131 Tositumomab for use in the Territory shall be limited to
the equivalent percentage of the funding contribution made by Amersham.
Shortages of Iodine I 131 Tositumomab which arise from shortages of Tositumomab
rather than a capacity constraint in connection with radiolabeling shall not be
allocated in accordance with this Section 3.11(a), but rather the available
Tositumomab shall be radiolabeled for use in the Territory or Corixa Territory
in accordance with the allocation by territory set forth in Section 3.11(b),
unless the Parties then agree differently.

               (b) ALLOCATION OF TOSITUMOMAB. Corixa shall place orders for
Tositumomab for use in the Territory following consultation with Amersham and in
accordance with the Forecast for the Territory and as agreed upon by the
Parties. Corixa shall place orders



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<PAGE>

for use in the Corixa Territory in its own discretion. Any orders placed with BI
Pharma or any other vendor of Tositumomab which is a supplier for use both
inside and outside of Territory (a "Vendor") shall be a "Vested Order" for
purposes of this Section 3.11(b), if it is a firm order which has been accepted
by the Vendor and is scheduled for delivery within [*] months after the date of
such order.

                   (i) VESTED ORDERS. To the extent that a Vendor is able to
deliver Tositumomab material in accordance with Vested Orders, such material
shall be purchased by, and the benefits and risks of ownership shall belong to,
the party which was responsible for such portion of the Vested Order. For
clarity, Amersham shall purchase that portion of the Vested Order that
corresponds to Amersham's estimation of its total requirements of Product
contained in Amersham's Forecast corresponding to the same [*] month period as
the Vested Order. Thus, Vested Orders which had been placed for the purpose of
supply in the Territory shall be allocated solely to the Territory for use by
Amersham and Vested Orders which had been placed for the purposes of supply
outside of the Territory shall be allocated solely to Corixa for use outside of
the Territory, in each case except by the mutual written agreement of the
parties.

                   (ii) SHORTAGE OF TOSITUMOMAB. Subject to the terms and
conditions of Section 3.1(e), in the event of shortages of Tositumomab, the
following rules shall apply:

                        (1) If Corixa seeks to place a Vested Order for
Tositumomab and is advised by a Vendor that such Vendor will not accept the full
amount of such order, whether such order is for purposes of supply in the
Territory or elsewhere in the world, then Corixa shall consult with Amersham
regarding the allocation of available supply. Unless the Parties otherwise
agree, all future Vested Orders shall be allocated [*]% to the Territory and
[*]% for use outside of the Territory so long as such conditions of supply
shortage prevail, with each lot being allocated in such pro rata manner. In the
event that, over the course of the [*] month period following such Vendor's
refusal to accept the full amount of such order, such Vendor also refuses to
accept the full amount of each and every subsequent order which Corixa attempts
to place as a Vested Order, the Parties shall meet to discuss a plan for
remedying such shortage of Tositumomab.

                        (2) If a Vendor is unable to deliver the full amount of
a Vested Order, either because the amount delivered is less than the amount
ordered or because some or all of the delivery is not accepted for any reason,
including, without limitation, non-compliance with Specifications, then the
available Tositumomab in each calendar year in which a shortage of supply
prevails shall be allocated as between the Territory and the rest of the world
[*] on the basis of the aggregate Vested Orders for delivery in that calendar
year that had been placed for use in the Territory and in the rest of the world.
If the shortfall or failure occurs in a batch which is part of a manufacturing
campaign, then the acceptable material manufactured as part of that campaign,
and all future deliveries in that calendar year, shall be allocated between the
Territory and the rest of the world so as to make the aggregate allocation of
material on a



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<PAGE>

year-to-date basis equal, as nearly as practicable, to such pro rata allocation.
(Such allocation on a campaign basis could require that material already
received as part of the same campaign for use in one territory be redesignated
for use in a different territory, if such redesignation is necessary in order to
achieve the specified pro rata allocation. However, material received as part of
previous campaigns shall not be redesignated except by mutual consent.) As used
herein, a "manufacturing campaign" shall refer to [*]. The allocation rule set
forth in this Section 3.11(b)(ii)(2) shall restart for each calendar year, [*]
for a particular territory in the prior calendar year.

                   (iii) In the event either Party desires to reduce the size of
a Vested Order previously placed, the percentage by which such Vested Order may
be reduced under the contract with the Vendor shall be applied equally to the
Territory and to the rest of the world unless the Parties otherwise agree. By
way of example, if the supply agreement permits a reduction in Vested Orders of
up to 25% for orders with delivery dates at a specified time period in the
future, and the Parties desire to reduce the Vested Order for that time period
in the Territory by 35% and the rest of the world by 10%, then the reduction for
the Territory shall be limited to 25% while the order for the rest of the world
is reduced by the full 10%. In that case, by mutual agreement, any further
reduction which would have been available for the order for the rest of the
world may be reallocated to permit a further reduction in the Vested Order for
the Territory.

                   (iv) If under the contract with the Vendor, Corixa is
obligated to take quantities of Tositumomab produced in excess of the amount
specified in the original Vested Order (e.g., as a result of the [*] of the
quantity of material produced in each batch or due to minimum batch sizes), then
at Corixa's option any excess quantities which Corixa is obligated to purchase
shall be allocated as between the Territory and the rest of the world pro rata
on the basis of the aggregate Vested Orders for delivery to each territory in
that calendar year.

                   (v) The purpose of the foregoing allocation rules is to
permit the Parties jointly (with respect to the Territory) and Corixa
independently (with respect to the rest of the world) to make their respective
long-term purchase decisions for Tositumomab, with the benefits and risks of
such purchase decisions to be allocated to the Parties jointly, or Corixa
independently, as the case may be.

               (c) ALLOCATION OF TERRITORY SUPPLIES IN FAVOR OF INITIAL APPROVAL
CLINICAL TRIAL. In the event of Product Shortages giving rise to allocation
under this Section 3.11, all quantities of Tositumomab and Iodine I 131
Tositumomab allocated to the Territory in accordance with this Section 3.11
shall be first allocated to supply the requirements of an Initial Approval
Clinical Trial in the Territory. After such requirements have been met, Amersham
shall decide, in its sole discretion, how the remainder of the Tositumomab and
Iodine I 131 Tositumomab allocated to the Territory is used.

        4. ECONOMICS.


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<PAGE>

           4.1 TRANSFER PRICE.

               (a) Subject to the next sentence and Section 4.1(b), Amersham
shall pay Corixa for the Tositumomab Corixa provides to Amersham and the Corixa
Iodine I 131 Tositumomab, a transfer price equal to the sum of (i) Fully
Allocated Costs for such Tositumomab or Corixa Iodine I 131 Tositumomab, as
applicable, and (ii) [*] percent ([*]%) of [*] for any Product containing or
comprising such Tositumomab (even if such Tositumomab is radiolabeled by or on
behalf of Amersham) or such Corixa Iodine I 131 Tositumomab (the "Transfer
Price"). For clinical trial supplies of Tositumomab and Corixa Iodine I 131
Tositumomab, the Transfer Price paid by Amersham shall exclude that part of the
Transfer Price described in (ii) above. Corixa shall pay for all such clinical
supplies that are designated for use in an Initial Approval Clinical Trial.
Amersham acknowledges that the Fully Allocated Costs for Tositumomab and Corixa
Iodine I 131 Tositumomab may vary depending on, among other factors, the then
current price paid to BI Pharma by Corixa for Tositumomab and the then current
price paid to Nordion by Corixa for Corixa Iodine I 131 Tositumomab. Amersham
shall pay the amount set forth in (i) within [*] days after the date of Corixa's
invoice therefor. It is anticipated that Corixa will send Amersham semi-annual
invoices for Tositumomab (except for Tositumomab designated for use in an
Initial Approval Clinical Trial) and monthly invoices for Corixa Iodine I 131
Tositumomab (except for Corixa Iodine I 131 Tositumomab designated for use in an
Initial Approval Clinical Trial). The amount set forth in (ii) shall be paid in
accordance with Section 4.4.

               (b) The percentage of [*] owed by Amersham pursuant to Section
4.1(a)(ii) shall be reduced to the applicable percentage shown below in a
particular country of the Territory during such time as one of the following
circumstances is then in effect in such country:


<TABLE>
<CAPTION>
                                                                     PERCENTAGE
        CIRCUMSTANCE                                                OF NET SALES
        ---------------                                             ------------
<S>                                                                    <C>
        (i)         [*]                                                 [*]%

        (ii)        [*]                                                 [*]%

        (iii)       [*]                                                 [*]%

        (iv)        [*]                                                 [*]%
</TABLE>

               (c) In the event that more than one circumstance set forth in
Section 4.1(b) occurs simultaneously in a particular country, Amersham's
percentage of [*] shall be the [*] percentage applicable to any of the
circumstances. Multiple such simultaneous circumstances shall [*] on the
percentage of [*] paid by Amersham.

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<PAGE>

           4.2 FULLY ALLOCATED COST AUDIT. Amersham shall have the right, upon
prior written notice to Corixa and at Amersham's cost, to have the certified
public accountants of Amersham's choice, bound by confidentiality and reasonably
acceptable to Corixa, audit Corixa's books and records to verify Corixa's
calculations of Fully Allocated Cost. Amersham may exercise this right no more
than once per contract year.

           4.3 QUARTERLY ACCOUNTING FOR TOSITUMOMAB STORED BY NORDION. Some of
the Tositumomab manufactured hereunder may be shipped to Nordion so that Nordion
can use such Tositumomab for the manufacture of Corixa Iodine I 131 Tositumomab.
Under normal circumstances, Amersham shall ordinarily pay the Transfer Price for
such Tositumomab after it is made into Corixa Iodine I 131 Tositumomab. Thus,
the Transfer Price will include both the Fully Allocated Costs of manufacturing
the Tositumomab and the Fully Allocated Cost of making Corixa Iodine I 131
Tositumomab from such Tositumomab. Corixa reserves the right to perform a
quarterly assessment of the amount of Amersham-earmarked Tositumomab being
stored by Nordion and the length of time that such Tositumomab has been stored
by Nordion. For all such Tositumomab that Nordion has stored for more than [*],
Corixa reserves the right to invoice Amersham for the Fully Allocated Cost of
such Tositumomab. Amersham shall pay such invoice within [*] days. If any such
Tositumomab is subsequently converted into Corixa Iodine I 131 Tositumomab,
Corixa's invoice for the Fully Allocated Cost of such Corixa Iodine I 131
Tositumomab shall include a credit for the amount already paid by Amersham.

           4.4 QUARTERLY PAYMENTS AND PAYMENT REPORTS. All payments due under
Section 4.1(a)(ii) shall be made to Corixa or its designee quarterly within 30
days following the end of each calendar quarter for which payments are due. Each
such payment shall be accompanied by a statement stating the number,
description, and aggregate Net Sales, by country, of each Product sold during
the relevant calendar quarter.

           4.5 PAYMENT METHOD. All payments due under this Agreement to Corixa
shall be made by bank wire transfer in immediately available funds to an account
designated by Corixa. All payments hereunder shall be made in U.S. dollars and
shall be noncreditable and nonrefundable.

           4.6 TAXES. Corixa shall pay any and all taxes levied on account of
all payments it receives under this Agreement. If laws or regulations require
that taxes be withheld, Amersham will (i) deduct those taxes from the remittable
payment, (ii) pay the taxes to the proper taxing authority, and (iii) send
evidence of the obligation together with proof of tax payment to Corixa within
60 days following that tax payment.

           4.7 BLOCKED CURRENCY. In each country in the Territory where the
local currency is blocked and cannot be removed from the country, royalties
accrued in that country shall be paid to Corixa in the country in local currency
by deposit in a local bank designated by Corixa, unless the Parties otherwise
agree.



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           4.8 SUBLICENSES. In the event Amersham grants licenses or sublicenses
to others to sell Products which are subject to payments under Section 4.1, such
licenses or sublicenses shall include an obligation for the licensee or
sublicensee to account for and report its sales of Products on the same basis as
if such sales were Net Sales by Amersham, and Amersham shall pay to Corixa, with
respect to such sales, payments as if such sales of the licensee or sublicensee
were Net Sales of Amersham.

           4.9 FOREIGN EXCHANGE. Payments due on sales of the Product shall be
calculated and paid by Amersham in United States Dollars. Sales will be
converted into U.S. Dollars from locally billed currency on a monthly basis
using the exchange rates for the last trading day of the month as published by
Reuters. Royalties will be calculated on a quarterly calendar basis and payments
shall be due thirty (30) days after the completion of the quarter.

           4.10 RECORDS; INSPECTION. Amersham shall keep complete, true and
accurate books of account and records for the purpose of determining the
payments to be made under this Agreement. Such books and records shall be kept
for at least three years following the end of the calendar quarter to which they
pertain. Such records will open for inspection during such three year period by
independent accountants, solely for the purpose of verifying payment statements
hereunder. Such inspections shall be made no more than once each calendar year,
at reasonable time and on reasonable notice. Inspections conducted under this
Section 4.10 shall be at the expense of Corixa, unless a variation or error
producing an increase exceeding [*]% of the [*] amount stated for any period
covered by the inspection is established in the course of such inspection,
whereupon all costs relating to the inspection for such period and any unpaid
amounts (plus interest) that are discovered will be paid promptly by Amersham.

           4.11 LATE PAYMENT PENALTY. Any payment due under this Article 4 that
is not paid by [*] days after the payment's due date shall accrue interest,
which must be paid by the Party with the payment obligation to the recipient
Party, on a daily basis at a rate equal to [*] percent above the then-applicable
reference rate of CitiBank, N.A. San Francisco, California (or the maximum
amount permitted by law, if less), from the date first owed until paid.

        5. INTELLECTUAL PROPERTY.

           5.1 OWNERSHIP. Corixa shall own the entire right, title and interest
in and to any and all Product Inventions, and Patents covering such Product
Inventions. Each Party shall own the entire right, title and interest in and to
any and all of its Sole Other Inventions, and Patents covering such Sole Other
Inventions. Amersham and Corixa shall each own an undivided one-half interest in
and to any and all Joint Other Inventions and Patents and other intellectual
property rights claiming or covering or arising from such Joint Other Inventions
(the "Joint Other Patents"), with inventorship to be determined under the patent
laws of the United States. Amersham and Corixa, as joint owners, shall each have
the right to practice and to grant licenses under such Joint Other Patents
without a duty of accounting, except as otherwise provided in this Agreement.
Amersham hereby covenants that it will not license any Joint Other Patents it
Controls for use in conjunction with an [*].


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<PAGE>

           5.2 DISCLOSURE. Amersham shall submit a written report to Corixa
within [*] days of the end of each quarter describing any Product Invention
arising during the prior quarter. The Parties shall mutually decide whether to
file a patent application for a Joint Other Invention, as discussed in Section
5.3.

           5.3 PATENT PROSECUTION AND MAINTENANCE; ABANDONMENT.

               (a) Each Party shall retain control over and bear all expenses
associated with the filing, prosecution and maintenance of all Patents claiming
its Sole Other Inventions.

               (b) Corixa shall retain control over and bear all expenses
associated with the filing, prosecution and maintenance of all Patents claiming
Product Inventions.

               (c) The Parties' rights and obligations with respect to the
filing, prosecution and maintenance of Joint Other Patents shall be decided on a
case-by-case basis.

           5.4 ENFORCEMENT OF PATENT RIGHTS.

               (a) If either Party becomes aware of any Third Party activity in
the Territory that infringes an issued Patent in the Corixa Intellectual
Property Rights or an issued Patent claiming a Product Invention, then that
Party shall give prompt written notice to the other Party within thirty (30)
days after having knowledge of such infringement. Corixa shall have the primary
right, but not the obligation, to institute, prosecute or control any action or
proceeding with respect to such infringement by counsel of its own choice.

               (b) If Corixa enforces a Patent that is part of the Corixa
Intellectual Property Rights or covers a Product Invention made by Amersham,
then (i) Amersham shall have the right (at its own expense) to participate in
such action and to be represented by counsel of its own choice, and (ii)
Amersham shall, at the request and expense of Corixa, be joined as a party to
the suit. Any damages or monetary award recovered shall be applied to reimburse
the reasonable costs and expenses of the Parties in connection with such
litigation and the balance shall be divided between Corixa and Amersham in
accordance with the percentage to which each such entity funded the suit.

               (c) If Corixa fails to bring an action or proceeding to enforce a
Patent that is part of the Corixa Intellectual Property Rights or covers a
Product Invention made by Amersham within a period of [*] days after such
notice, then Amersham shall have the right, but not the obligation, to bring and
control any such action by counsel of its own choice, and Corixa shall have the
right to participate in such action and to be represented, at its own expense,
by counsel of its own choice. Any damages or monetary award recovered shall be
applied to reimburse the reasonable costs and expenses of the Parties in
connection with such litigation and the balance shall be divided between Corixa
and Amersham in accordance with the percentage to which each such entity funded
the suit.


----------
* Confidential Treatment Requested.


                                       20
<PAGE>

           5.5 DEFENSE OF THIRD PARTY CLAIMS.

               (a) If a claim is brought by a Third Party that any activity
related to the Agreement or a Product infringes the intellectual property rights
of such Third Party, each Party will give prompt written notice to the other
Party of such claim. If the Third Party claim arises from Corixa's activities
under the Agreement, Corixa shall control and bear the expense of its own
defense and, except as set forth in Section 5.5(b), Corixa shall defend,
indemnify and hold harmless Amersham, which shall include costs or judgments
whether for money or equitable relief, and reasonable legal expenses and
reasonable attorney's fees. Corixa shall not enter into a settlement agreement
with such Third Party without the written consent of Amersham, which shall not
be unreasonably withheld. If the Third Party claim arises from Amersham's
activities under the Agreement or from a Product, Amersham shall control and
bear the expense of its own defense and Amersham shall defend, indemnify and
hold harmless Corixa, which shall include costs or judgments whether for money
or equitable relief, and reasonable legal expenses and reasonable attorney's
fees. Amersham shall not enter into a settlement agreement with such Third Party
without the written consent of Corixa, which shall not be unreasonably withheld.

               (b) Except as set forth in Section 5.5(a), each Party shall be
responsible for its own defense of such Third Party claims, at its own expense
and without indemnification by the other Party. In any event, neither Party
shall be required to conduct any work under this Agreement which it believes may
infringe Third Party rights. In the event the Third Party claim arises from the
manufacture, sale or use of a Product by Amersham or its licensee, the indemnity
obligations of Amersham under Section 5.5(a) shall apply, and Corixa shall not
have any indemnity obligation to Amersham in respect of such claims.

               5.6 TRADEMARKS. Amersham shall be responsible for the acquisition
and maintenance of trademarks for the Product in the Territory. Amersham is not
licensed to use any trademark Controlled by Corixa.



                                       21
<PAGE>

        6. CONFIDENTIALITY.

           6.1 NONDISCLOSURE OF CONFIDENTIAL INFORMATION. All Information
disclosed by one Party to the other Party pursuant to this Agreement shall be
"Confidential Information." The Parties agree that during the term of this
Agreement, and for a period of five years after this Agreement expires or
terminates, a Party receiving Confidential Information of the other Party will
(i) maintain in confidence such Confidential Information to the same extent such
Party maintains its own proprietary industrial information of similar kind and
value (but at a minimum each Party shall use commercially reasonable efforts),
(ii) not disclose such Confidential Information to any Third Party without prior
written consent of the other Party, except for disclosures made in confidence to
any Third Party manufacturer of Tositumomab or Iodine I 131 Tositumomab, and
(iii) not use such Confidential Information for any purpose except those
permitted by this Agreement.

           6.2 EXCEPTIONS. The obligations in Section 6.1 shall not apply with
respect to any portion of the Confidential Information that the receiving Party
can show by competent written proof:

               (a) Is publicly disclosed by the disclosing Party, either before
or after it is disclosed to the receiving Party hereunder; or

               (b) Was known to the receiving Party, without obligation to keep
it confidential, prior to disclosure by the disclosing Party; or

               (c) Is subsequently disclosed to the receiving Party by a Third
Party lawfully in possession thereof and without obligation to keep it
confidential; or

               (d) Has been published by a Third Party; or

               Has been independently developed by the receiving Party without
the aid, application or use of Confidential Information.

           6.3 AUTHORIZED DISCLOSURE. A Party may disclose the Confidential
Information belonging to the other Party to the extent such disclosure is
reasonably necessary in the following instances:

               (a) Filing or prosecuting Patents relating to Sole Inventions,
Joint Inventions or Products;

               (b) Regulatory filings;

               (c) Prosecuting or defending litigation;

               (d) Complying with applicable governmental regulations; and

               (e) Disclosure, in connection with the performance of this
Agreement, to Affiliates, sublicensees, research collaborators, employees,
consultants, or agents, each of



                                       22
<PAGE>

whom prior to disclosure must be bound by similar obligations of confidentiality
and non-use at least equivalent in scope to those set forth in this Article 6.

        In addition, Corixa shall have the right to disclose Confidential
Information under in connection with discussing potential business transactions
involving the Product outside of the Territory provided that Corixa and the
party to which Corixa is disclosing the Confidential Information are parties to
a written confidentiality agreement.

        The Parties acknowledge that the terms of this Agreement shall be
treated as Confidential Information of both Parties. Such terms may be disclosed
by a Party to investment bankers, investors, and potential investors, each of
whom prior to disclosure must be bound by similar obligations of confidentiality
and non-use at least equivalent in scope to those set forth in this Article 6.
In addition, a copy of this Agreement may be filed by Corixa with the Securities
and Exchange Commission. In connection with any such filing, Corixa shall
endeavor to obtain confidential treatment of economic and trade secret
information.

        In any event, the Parties agree to take all reasonable action to avoid
disclosure of Confidential Information except as permitted hereunder.

           6.4 TERMINATION OF PRIOR AGREEMENTS. This Agreement supersedes all
mutual non-disclosure agreements entered into by the Parties prior to the
Effective Date. All Information exchanged between the Parties under those
earlier agreements shall be deemed Confidential Information and shall be subject
to the terms of this Article 6.

           6.5 PUBLICITY. The Parties shall agree on the language of the public
announcement of the execution of this Agreement prior to the release thereof.
Any other publication, news release or other public announcement relating to
this Agreement or to the performance hereunder, shall first be reviewed and
approved by both Parties; provided, however, that any disclosure which is
required by law as advised by the disclosing Party's counsel may be made without
the prior consent of the other Party, although the other Party shall be given
prompt notice of any such legally required disclosure and to the extent
practicable shall provide the other Party an opportunity to comment on the
proposed disclosure. The Parties shall agree on language relating to this
Agreement which either Party may use without the repeated approval of the other
Party.

           6.6 PUBLICATIONS. Amersham shall not publish or present the results
of Clinical Trials carried out in the Territory under this Agreement without the
opportunity for prior review by Corixa. Subject to Section 6.3, Amersham agrees
to provide Corixa the opportunity to review any proposed abstracts, manuscripts
or presentations (including verbal presentations) which relate to any Product at
least 30 days prior to its intended submission for publication and agrees, upon
request, not to submit any such abstract or manuscript for publication until
Corixa is given a reasonable period of time to secure patent protection for any
material in such publication which it believes to be patentable. Both Parties
understand that a reasonable commercial strategy may require delay of
publication of information or filing of patent applications. The Parties agree
to review and consider delay of publication and filing of patent applications
under certain circumstances. Neither Party shall have the right to publish or
present



                                       23
<PAGE>

Confidential Information of the other Party which is subject to Section 6.1.
Nothing contained in this Section 6.6 shall prohibit the inclusion of
information necessary for a patent application, except for Confidential
Information of the nonfiling Party, provided the nonfiling Party is given a
reasonable opportunity to review the information to be included prior to
submission of such patent application.

        7. TERM AND TERMINATION.

           7.1 TERM. This Agreement shall become effective on the Effective Date
and shall remain in effect until the sooner to occur of (a) the expiration or
termination for any reason by the Parties of the License Agreement, (b) Corixa's
inability to supply Amersham's Product needs in the Territory pursuant to terms
and conditions hereunder, (c) termination by Corixa due to Amersham's failure to
establish a European Facility in accordance with Section 3.3(d) herein, or (d)
termination of this Agreement by a Party for material breach pursuant to Section
7.2 below, including, without limitation, Amersham's failure to comply with the
terms and conditions of the BI Pharma Agreements and Nordion Agreements
applicable to Amersham.

           7.2 TERMINATION FOR MATERIAL BREACH.

               (a) If either Party believes that the other is in material breach
of this Agreement (including without limitation any material breach of a
representation or warranty made in this Agreement), then the non-breaching Party
may deliver notice of such breach to the other Party. In such notice the
non-breaching Party shall identify the actions or conduct that such Party would
consider to be an acceptable cure of such breach. The allegedly breaching Party
shall have [*] days to either cure such breach or, if cure cannot be reasonably
effected within such [*] day period, to deliver to the other Party a plan for
curing such breach which is reasonably sufficient to effect a cure. Such a plan
shall set forth a program for achieving cure as rapidly as practicable.
Following delivery of such plan, the breaching Party shall use Diligent Efforts
to carry out the plan and cure the breach. In the event of breach for failure to
meet any payment obligations under this Agreement, the breaching Party shall
have [*] days to cure such breach for nonpayment. For the avoidance of any
doubt, any failure on the part of Nycomed, Inc. to fulfill its obligations set
forth in the Stock Purchase Agreement shall be a material breach of this
Agreement.

               (b) If the Party receiving notice of breach fails to cure such
breach within the [*] period, or the Party providing the notice reasonably
determines that the proposed corrective plan or the actions being taken to carry
it out is not commercially practicable, the Party originally delivering the
notice may terminate this Agreement upon [*] advance written notice. If Corixa
is the breaching Party, Amersham may elect to not terminate this Agreement as
provided herein. If the non-breaching Party elects not to terminate this
Agreement under circumstances in which such non-breaching Party believes it is
entitled to a temporary restraining order against the breaching Party, it may
seek such a temporary restraining order. After the issuance of any temporary
restraining order granted hereunder, any disputes concerning the appropriateness
of such temporary restraining order shall be resolved in accordance with Section


----------
* Confidential Treatment Requested.


                                       24
<PAGE>

10.1 and, if arbitration results, the arbitrator shall have the right to grant
the Party subject to such temporary restraining order any redress that might
have been available to such Party if the matter had remained under the
jurisdiction of the courts.

               (c) If a Party gives notice of termination under this Section 7.2
and the other Party disputes whether such notice was proper, then the issue of
whether this Agreement has been terminated shall be resolved in accordance with
Section 10.1. If as a result of such dispute resolution process it is determined
that the notice of termination was proper, then such termination shall be deemed
to have been effective 30 days following the date of the notice of termination.
If as a result of such dispute resolution process it is determined that the
notice of termination was improper, then no termination shall have occurred and
this Agreement shall have remained in effect.

           7.3 EFFECT OF TERMINATION; SURVIVAL.

               (a) In the event of termination of this Agreement for any reason,
the following provisions of this Agreement shall survive: Sections 4.10, 4.11,
5.1, 5.3, 6.1, 6.2, 6.3 and 7.3, and Articles 1, 9 and 10.

               (b) In any event, termination of this Agreement shall not relieve
the Parties of any liability which accrued hereunder prior to the effective date
of such termination nor preclude either Party from pursuing all rights and
remedies it may have hereunder or at law or in equity with respect to any breach
of this Agreement nor prejudice either Party's right to obtain performance of
any obligation.

               (c) In the event of termination of this Agreement as a result of
Amersham's termination of the License Agreement pursuant to Section 11.4(a) of
the License Agreement, Corixa may, at its sole discretion, purchase from
Amersham some or all of the Tositumomab and Corixa Iodine I 131 Tositumomab that
Amersham purchased for commercial use and for which Amersham paid Corixa in full
prior to the effective date of such termination. Corixa shall pay Amersham any
mutually agreed purchase price for such Tositumomab and Corixa Iodine I 131
Tositumomab, provided such price does not exceed the price originally paid by
Amersham to Corixa. Amersham shall destroy all Tositumomab and Corixa Iodine I
131 Tositumomab not purchased by Corixa within [*] days of such termination.

        8. REPRESENTATIONS AND COVENANTS.

           8.1 MUTUAL AUTHORITY. Corixa and Amersham each represents and
warrants to the other that (i) it has the authority and right to enter into and
perform this Agreement and (ii) its execution, delivery and performance of this
Agreement will not conflict in any material fashion with the terms of any other
agreement to which it is or becomes a party or by which it is or becomes bound.

           8.2 PERFORMANCE BY AFFILIATES. The Parties recognize that each may
perform some or all of its obligations under this Agreement through Affiliates,
provided, however, that


----------
* Confidential Treatment Requested.


                                       25
<PAGE>

each Party shall remain responsible and be guarantor of the performance by its
Affiliates and shall cause its Affiliates to comply with the provisions of this
Agreement in connection with such performance.

        9. INDEMNIFICATION AND LIMITATION OF LIABILITY.

           9.1 INDEMNIFICATION.

               (a) Amersham hereby agrees to defend and hold harmless Corixa and
its agents and employees from and against any and all suits, claims, actions,
demands, liabilities, expenses and/or loss, including reasonable legal expenses
and reasonable attorneys' fees ("Losses") resulting directly or indirectly from
(i) manufacture, use or storage by Amersham or its sublicensee or agent of
Tositumomab, Iodine I 131 Tositumomab or Product or (ii) sale of Product in the
Territory, except to the extent such Losses result from an activity as to which
Corixa is obliged to indemnify Amersham pursuant to Section 9.1(b).

               (b) Corixa hereby agrees to defend and hold harmless Amersham and
its agents and employees from and against any and all suits, claims, actions,
demands, liabilities, expenses and/or loss, including reasonable legal expenses
and reasonable attorneys' fees ("Losses") resulting directly or indirectly from
(i) the failure of Tositumomab provided to Amersham by Corixa or Corixa Iodine I
131 Tositumomab to comply with the relevant Specifications or (ii) the failure
of Corixa to comply with GMP during its manufacture of Tositumomab or Corixa
Iodine I 131 Tositumomab, except to the extent such Losses result from an
activity as to which Amersham is obliged to indemnify Corixa pursuant to Section
9.1(a).

               (c) In the event that a Party (the "Indemnified Party") is
seeking indemnification under Section 9.1(a) or (b), the Indemnified Party shall
inform the other Party (the "Indemnifying Party") of a claim as soon as
reasonably practicable after the Indemnified Party receives notice of the claim,
shall permit the Indemnifying Party to assume direction and control of the
defense of the claim (including the right to settle the claim solely for
monetary consideration), and shall cooperate as requested by the Indemnifying
Party (at the expense of the Indemnifying Party) in the defense of the claim.

           9.2 LIMITATION OF LIABILITY. EXCEPT AS SPECIFICALLY PROVIDED IN
SECTION 9.1, IN NO EVENT SHALL EITHER PARTY, ITS DIRECTORS, OFFICERS, EMPLOYEES,
AGENTS OR AFFILIATES BE LIABLE TO THE OTHER PARTY FOR ANY INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES, WHETHER BASED UPON A CLAIM OR
ACTION OF CONTRACT, WARRANTY, NEGLIGENCE, STRICT LIABILITY OR OTHER TORT, OR
OTHERWISE, ARISING OUT OF THIS AGREEMENT. For clarification, the foregoing
sentence shall not be interpreted to limit or to expand the express rights
specifically granted in the sections of this Agreement.

        10. MISCELLANEOUS.

            10.1 DISPUTE RESOLUTION. In the event of any controversy or claim
arising out of, relating to or in connection with any provision of this
Agreement, the Parties shall try to settle



                                       26
<PAGE>

their differences amicably between themselves first, by referring the disputed
matter to the respective heads of Research and Development of each Party and, if
not resolved by the Research and Development heads, by referring the disputed
matter to the respective Chief Executive Officers of each Party. Either Party
may initiate such informal dispute resolution by sending written notice of the
dispute to the other Party, and, within [*] days after such notice, such
representatives of the Parties shall meet for attempted resolution by good faith
negotiations. If such personnel are unable to resolve a dispute within [*] days
of their first meeting of such negotiations, except as provided in Section 10.3,
either Party may seek to have such dispute resolved by binding arbitration with
a single arbitrator under the commercial rules of the American Arbitration
Association. The Parties hereby consent to conduct such binding arbitration
procedures in English in the city of New York, New York.

            10.2 GOVERNING LAW. Resolution of all disputes arising out of or
related to this Agreement or the performance, enforcement, breach or termination
of this Agreement and any remedies relating thereto, shall be governed by and
construed under the substantive laws of the State of Delaware, as applied to
agreements executed and performed entirely in the State of Delaware by residents
of the State of Delaware, without regard to conflicts of law rules.

            10.3 PATENTS AND TRADEMARKS. Any dispute, controversy or claim
relating to the scope, validity, enforceability or infringement of any Patent
rights covering the manufacture, use or sale of any Product or of any trademark
rights related to any Product shall be submitted to a court of competent
jurisdiction in the territory in which such Patent or trademark rights were
granted or arose.

            10.4 ENTIRE AGREEMENT; AMENDMENT. This Agreement sets forth the
complete, final and exclusive agreement and all the covenants, promises,
agreements, warranties, representations, conditions and understandings between
the Parties hereto and supersedes and terminates all prior agreements and
understandings between the Parties. There are no covenants, promises,
agreements, warranties, representations, conditions or understandings, either
oral or written, between the Parties other than as are set forth herein and
therein. No subsequent alteration, amendment, change or addition to this
Agreement shall be binding upon the Parties unless reduced to writing and signed
by an authorized officer of each Party.

            10.5 EXPORT CONTROL. This Agreement is made subject to any
restrictions concerning the export of products or technical information from the
United States of America or other countries which may be imposed upon or related
to Corixa or Amersham from time to time. Each Party agrees that it will not
export, directly or indirectly, any technical information acquired from the
other Party under this Agreement or any products using such technical
information to a location or in a manner that at the time of export requires an
export license or other governmental approval, without first obtaining the
written consent to do so from the appropriate agency or other governmental
entity.

            10.6 FORCE MAJEURE. Both Parties shall be excused from the
performance of their obligations under this Agreement to the extent that such
performance is prevented by force

----------------
Confidential Treatment Requested.

                                       27
<PAGE>

majeure and the nonperforming Party promptly provides notice of the prevention
to the other Party. Such excuse shall be continued so long as the condition
constituting force majeure continues and the nonperforming Party takes
reasonable efforts to remove the condition. For purposes of this Agreement,
force majeure shall include conditions beyond the control of the Parties,
including without limitation, an act of God, voluntary or involuntary compliance
with any regulation, law or order of any government, war, civil commotion, labor
strike or lock-out, epidemic, failure or default of public utilities or common
carriers, destruction of production facilities or materials by fire, earthquake,
storm or like catastrophe; provided, however, the payment of invoices due and
owing hereunder shall not be delayed by the payer because of a force majeure
affecting the payer.

            10.7 NOTICES. Any notice required or permitted to be given under
this Agreement shall be in writing, shall specifically refer to this Agreement
and shall be deemed to have been sufficiently given for all purposes if mailed
by first class certified or registered mail, postage prepaid, express delivery
service or personally delivered. Unless otherwise specified in writing, the
mailing addresses of the Parties shall be as described below.

                   For Corixa:         Senior VP, and Chief Operating Officer
                                       Corixa Corporation
                                       1124 Columbia Street, Suite 200
                                       Seattle, WA 98104

                   With a copy to:     General Counsel
                                       Corixa Corporation
                                       1124 Columbia Street, Suite 200
                                       Seattle, WA 98104

                   With a copy to:     Cooley Godward LLP
                                       Five Palo Alto Square
                                       3000 El Camino Real
                                       Palo Alto, CA 94306
                                       Attention: Robert L. Jones, Esq.

                   For Amersham:       Group Secretary
                                       Amersham PLC
                                       Amersham Place
                                       Little Chalfont
                                       Buckinghamshire
                                       ENGLAND HP7 9NA

                   With a copy to:     General Counsel
                                       Amersham Health, Inc.
                                       101 Carnegie Center
                                       Princeton, NJ 08540



                                       28
<PAGE>

           10.8 CONSENTS NOT UNREASONABLY WITHHELD OR DELAYED. Whenever
provision is made in this Agreement for either Party to secure the consent or
approval of the other, that consent or approval shall not unreasonably be
withheld or delayed, and whenever in this Agreement provisions are made for one
Party to object to or disapprove a matter, such objection or disapproval shall
not unreasonably be exercised.

            10.9 MAINTENANCE OF RECORDS. Each Party shall keep and maintain all
records required by law or regulation with respect to Products and shall make
copies of such records available to the other Party upon request.

            10.10 UNITED STATES DOLLARS. References in this Agreement to
"Dollars" or "$" shall mean the legal tender of the United States of America.

            10.11 NO STRICT CONSTRUCTION. This Agreement has been prepared
jointly and shall not be strictly construed against either Party.

            10.12 ENGLISH. This Agreement has been prepared in English and shall
be interpreted solely in English.

            10.13 ASSIGNMENT. Neither Party may assign or transfer this
Agreement or any rights or obligations hereunder without the prior written
consent of the other, except a Party may make such an assignment without the
other Party's consent to an Affiliate or to a successor to substantially all of
the business of such Party, whether in a merger, sale of stock, sale of assets
or other transaction. Any permitted successor or assignee of rights and/or
obligations hereunder shall, in writing to the other Party, expressly assume
performance of such rights and/or obligations. Any permitted assignment shall be
binding on the successors of the assigning Party. Any assignment or attempted
assignment by either Party in violation of the terms of this Section 10.13 shall
be null and void and of no legal effect.

            10.14 HARDSHIP. If, during the term of the Agreement, performance of
the Agreement should lead to unreasonable hardship for one or other Party taking
the interests of both Parties into account both Parties shall endeavor to agree
in good faith to amend the Agreement in the light of the change in
circumstances.

            10.15 ELECTRONIC DATA INTERCHANGE. If both Parties elect to
facilitate business activities hereunder by electronically sending and receiving
data in agreed formats (also referred to as Electronic Data Interchange or
"EDI") in substitution for conventional paper-based documents, the terms and
conditions of this Agreement shall apply to such EDI activities.

            10.16 COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

            10.17 FURTHER ACTIONS. Each Party agrees to execute, acknowledge and
deliver such further instruments, and to do all such other acts, as may be
necessary or appropriate in order to carry out the purposes and intent of this
Agreement.



                                       29
<PAGE>

            10.18 SEVERABILITY. If any one or more of the provisions of this
Agreement is held to be invalid or unenforceable by any court of competent
jurisdiction from which no appeal can be or is taken, the provision shall be
considered severed from this Agreement and shall not serve to invalidate any
remaining provisions hereof. The Parties shall make a good faith effort to
replace any invalid or unenforceable provision with a valid and enforceable one
such that the objectives contemplated by the Parties when entering this
Agreement may be realized. If the Parties, after making good faith effort, are
unable to effectively replace an invalid or unenforceable provision pursuant to
this Section 10.18, and a Party is suffering or reasonably expects to suffer
significant economic harm as a result of the invalidity or unenforceability of
an original provision of this Agreement, such Party shall have the right to
terminate this Agreement upon six months prior written notice to the other
Party. Such termination shall be in accordance with the provisions of Section
7.3 of this Agreement.

            10.19 AMBIGUITIES. Ambiguities, if any, in this Agreement shall not
be construed against any Party, irrespective of which Party may be deemed to
have authored the ambiguous provision.

            10.20 HEADINGS. The headings for each article and section in this
Agreement have been inserted for convenience of reference only and are not
intended to limit or expand on the meaning of the language contained in the
particular article or section.

            10.21 NO WAIVER. Any delay in enforcing a Party's rights under this
Agreement or any waiver as to a particular default or other matter shall not
constitute a waiver of such Party's rights to the future enforcement of its
rights under this Agreement, excepting only as to an express written and signed
waiver as to a particular matter for a particular period of time.

        IN WITNESS WHEREOF, the Parties have executed this Agreement in
duplicate originals by their proper officers as of the date and year first above
written.

AMERSHAM PLC                                CORIXA CORPORATION

By: /S/ R.E.B. Allnult                      By: /s/ Steven Gillis
   ----------------------------                ------------------------------

Name: R.E.B. Allnult                        Name:  Steven Gillis
     --------------------------                    --------------------------

Title: Company Secretary                    Title: Chairman and Chief
      -------------------------                    Executive Officer
                                                   --------------------------

Date:  11/05/01                             Date:   11/01/01
     --------------------------                    --------------------------



                                       30
<PAGE>

                                    EXHIBIT A

                                 CORIXA FORECAST



<TABLE>
<CAPTION>
        CALENDAR YEAR                                   AMOUNT
        -------------                                  ---------
<S>                                                   <C>
             2001                                      [*] grams
             2002                                      [*] grams
             2003                                      [*] grams
</TABLE>



----------
* Confidential Treatment Requested.


                                      A-1

<PAGE>

                                    EXHIBIT B

                                EUROPEAN FACILITY

                            MILESTONES AND TIMELINES



<TABLE>
<CAPTION>
MILESTONE                                 TIMELINE
---------                                 --------
<S>                                      <C>
[*]                                       Within [*] days following the Effective Date
[*]                                       June 30, [*]
[*]                                       Beginning June 30, [*]
[*]                                       December 30, [*]
[*]                                       Completed by September 30, [*]
</TABLE>



----------
* Confidential Treatment Requested.


                                      B-1

<PAGE>

<TABLE>
<S>         <C>                                                                                                    <C>
1.          Definitions.............................................................................................1
            1.1         "Amersham Iodine I 131 Tositumomab".........................................................1
            1.2         "BI Pharma Agreements"......................................................................1
            1.3         "Clinical Trial"............................................................................1
            1.4         "Controlled"................................................................................1
            1.5         "Corixa"....................................................................................2
            1.6         "Corixa Intellectual Property Rights".......................................................2
            1.7         "Corixa Iodine I 131 Tositumomab"...........................................................2
            1.8         "Corixa Territory"..........................................................................2
            1.9         "Diligent Efforts"..........................................................................2
            1.10        "Effective Date"............................................................................2
            1.11        "European Facility".........................................................................2
            1.12        "Fully Allocated Cost"......................................................................2
            1.13        "Good Clinical Practice"....................................................................3
            1.14        "Good Laboratory Practice"..................................................................3
            1.15        "Good Manufacturing Practice"...............................................................3
            1.16        "Information"...............................................................................3
            1.17        "Initial Approval Clinical Trials"..........................................................3
            1.18        "Initial Development Plan"..................................................................4
            1.19        "Intellectual Property Rights"..............................................................4
            1.20        "Invention".................................................................................4
            1.21        "Iodine I 131 Tositumomab"..................................................................4
            1.22        "Joint Other Inventions"....................................................................4
            1.23        "Know-How"..................................................................................4
            1.24        "Net Sales".................................................................................4
            1.25        "Nordion Agreements"........................................................................5
            1.26        "Other Invention"...........................................................................5
            1.27        "Patent"....................................................................................5
            1.28        "Product"...................................................................................5
            1.29        "Product Invention".........................................................................5
            1.30        "QA/QC Costs"...............................................................................5
</TABLE>


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<TABLE>
<S>        <C>                                                                                                     <C>
            1.31        "Sole Other Inventions".....................................................................5
            1.32        "Specifications"............................................................................5
            1.33        "Stock Purchase Agreement"..................................................................6
            1.34        "Territory".................................................................................6
            1.35        "Therapy"...................................................................................6
            1.36        "Third Party"...............................................................................6
            1.37        "Tositumomab"...............................................................................6
            1.38        "Transfer Price"............................................................................6

2.          General Understanding...................................................................................6

3.          Manufacturing And Supply Of Antibody....................................................................6
            3.1         Tositumomab.................................................................................6
            3.2         Corixa Iodine I 131 Tositumomab.............................................................8
            3.3         Amersham Iodine I 131 Tositumomab..........................................................10
            3.4         Distribution...............................................................................12
            3.5         Customer Orders............................................................................12
            3.6         Enhancements...............................................................................12
            3.7         Manufacturing Regulatory Compliance........................................................13
            3.8         Regulatory Compliance......................................................................13
            3.9         Quality Control; Testing...................................................................13
            3.10        Non-Compliance with Specifications.........................................................13
            3.11        Allocation in the Event of Product Shortages...............................................14

4.          Economics..............................................................................................16
            4.1         Transfer Price.............................................................................16
            4.2         Fully Allocated Cost Audit.................................................................17
            4.3         Quarterly Accounting for Tositumomab Stored by Nordion.....................................18
            4.4         Quarterly Payments and Payment Reports.....................................................18
            4.5         Payment Method.............................................................................18
            4.6         Taxes......................................................................................18
            4.7         Blocked Currency...........................................................................18
            4.8         Sublicenses................................................................................18
            4.9         Foreign Exchange...........................................................................19
            4.10        Records; Inspection........................................................................19
</TABLE>


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<TABLE>
<S>        <C>                                                                                                     <C>
            4.11        Late Payment Penalty.......................................................................19

5.          Intellectual Property..................................................................................19
            5.1         Ownership..................................................................................19
            5.2         Disclosure.................................................................................19
            5.3         Patent Prosecution and Maintenance; Abandonment............................................19
            5.4         Enforcement of Patent Rights...............................................................20
            5.5         Defense of Third Party Claims..............................................................20
            5.6         Trademarks.................................................................................21

6.          Confidentiality........................................................................................21
            6.1         Nondisclosure of Confidential Information..................................................21
            6.2         Exceptions.................................................................................21
            6.3         Authorized Disclosure......................................................................22
            6.4         Termination of Prior Agreements............................................................22
            6.5         Publicity..................................................................................23
            6.6         Publications...............................................................................23

7.          Term And Termination...................................................................................23
            7.1         Term.......................................................................................23
            7.2         Termination for Material Breach............................................................23
            7.3         Effect of Termination; Survival............................................................24

8.          Representations And Covenants..........................................................................25
            8.1         Mutual Authority...........................................................................25
            8.2         Performance by Affiliates..................................................................25

9.          Indemnification And Limitation Of Liability............................................................25
            9.1         Indemnification............................................................................25
            9.2         Limitation of Liability....................................................................26

10.         Miscellaneous..........................................................................................26
            10.1        Dispute Resolution.........................................................................26
            10.2        Governing Law..............................................................................26
            10.3        Patents and Trademarks.....................................................................26
            10.4        Entire Agreement; Amendment................................................................27
            10.5        Export Control.............................................................................27
            10.6        Force Majeure..............................................................................27
</TABLE>

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<TABLE>
<S>        <C>                                                                                                     <C>
            10.7        Notices....................................................................................27
            10.8        Consents Not Unreasonably Withheld or Delayed..............................................28
            10.9        Maintenance of Records.....................................................................28
            10.10       United States Dollars......................................................................28
            10.11       No Strict Construction.....................................................................28
            10.12       English....................................................................................28
            10.13       Assignment.................................................................................28
            10.14       Hardship...................................................................................29
            10.15       Electronic Data Interchange................................................................29
            10.16       Counterparts...............................................................................29
            10.17       Further Actions............................................................................29
            10.18       Severability...............................................................................29
            10.19       Ambiguities................................................................................29
            10.20       Headings...................................................................................29
            10.21       No Waiver..................................................................................29
</TABLE>