Document:

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                                                                    EXHIBIT 10.1

                                 --------------

                               CORIXA CORPORATION

                                       AND

                       MEDICIS PHARMACEUTICAL CORPORATION

                                 --------------

                         DEVELOPMENT, COMMERCIALIZATION
                                       AND
                                LICENSE AGREEMENT

                                 --------------

*Certain confidential information contained in this document, marked by
brackets, has been omitted and filed with the Securities and Exchange Commission
pursuant to Rule 406 of the Securities Act of 1933, as amended.

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              DEVELOPMENT, COMMERCIALIZATION AND LICENSE AGREEMENT

       This DEVELOPMENT, COMMERCIALIZATION AND LICENSE AGREEMENT, together with
the exhibits attached hereto (the "Agreement") is entered into as of August 15,
2000 (the "Execution Date") by and between Corixa Corporation, a corporation
organized and existing under the laws of Delaware and having its principal
office at 1124 Columbia Street, Suite 200, Seattle, Washington 98104-2040
("Corixa"), and Medicis Pharmaceutical Corporation, a corporation organized and
existing under the laws of Delaware and having its principal office at 8125
North Hayden Road, Scottsdale, Arizona, 85258 ("Medicis").

                                    RECITALS

       WHEREAS, Corixa has scientific expertise, proprietary information and
biological materials related to the development of materials that may lead to
immune system-based therapy, or immunotherapy, products;

       WHEREAS, Medicis has expertise in developing and commercializing
therapeutic products;

       WHEREAS, Corixa and Medicis desire to collaborate in the development and
commercialization of immunotherapy products for the treatment of psoriasis in
humans in the United States and Canada; and

       WHEREAS, subject to the terms and conditions of this Agreement, Corixa
has agreed to grant to Medicis certain rights under intellectual property owned
or otherwise controlled by Corixa in the United States and Canada relating to
such products.

       NOW, THEREFORE, for and in consideration of the mutual observance of the
covenants hereinafter set forth and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereto
agree as follows:

1.     DEFINITIONS.

       For the purposes of this Agreement, the following words and phrases shall
have the following meanings:

       1.1 "Additional Technology" shall have the meaning set forth in Section
4.1(e).

       1.2 "Affiliate" of an entity means, for so long as one of the following
relationships is maintained, any corporation or other business entity owned by,
owning, or under common ownership with a party to this Agreement to the extent
of more than fifty percent (50%) of the equity (or such lesser percentage that
is the maximum allowed to be owned by a foreign corporation in a particular
jurisdiction) having the power to vote on or direct the affairs of the entity or
any person, firm, partnership, corporation or other entity actually controlled
by, controlling or under common control with a party to this Agreement.

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       1.3 "Collaboration" shall mean the joint collaboration of Corixa and
Medicis conducted in accordance with the Development and Commercialization
Program pursuant to the terms of this Agreement.

       1.4 "Commercialization Steering Committee" shall have the meaning set
forth in Section 3.2.

       1.5 "Confidential Information" shall have the meaning set forth in
Section 12.3.

       1.6 "Corixa Inventions" shall have the meaning set forth in Section 10.

       1.7 "Corixa Know-How" shall mean all technical information, materials and
know-how, including Corixa Inventions, except to the extent published or
included in any patent application, solely or jointly owned or controlled by
Corixa or which becomes owned or controlled by Corixa [*] that relates to the
PVAC Technology and that Corixa has the ability to license, and shall include,
without limitation, all [*].

       1.8 "Corixa Patents" shall mean, collectively, (a) all patent
applications and patents identified on Exhibit A, (b) all patent applications
and patents within the rights and licenses granted to Corixa pursuant to the
Corixa Third Party Licensor Agreements during the term of this Agreement, and
(c) all patent applications and patents that claim inventions or discoveries
that are made, conceived, developed or reduced to practice solely by Corixa or
jointly by Corixa and any Third Party prior to [*] to the extent in the case of
such joint inventions and discoveries that Corixa has the right to grant rights
and licenses thereunder on the terms and conditions hereof; to the extent that
the patent applications and patents set forth in (a), (b) and (c) [*]. Included
within the definition of Corixa Patents are any and all continuations,
continuations-in-part (solely to the extent such continuation(s) in part
contain(s) subject matter referred to in (i), (ii), (iii), (iv) or (v)),
divisions, patents of addition, reissues, renewals and extensions, and any and
all foreign counterparts, of any patent application or patent referred to in
this Section 1.8. Corixa Patents shall not include any patent application or
patent that is a patent application or patent within either the Medicis Patents
or the Joint Patents.

       1.9 "Corixa Third Party Licensor Agreements" shall mean the certain
agreements identified on Exhibit B, as amended from time to time in accordance
with Section 17.4.

       1.10 "Corixa Third Party Collaboration Agreements" shall mean the certain
agreements entered into by and between Corixa and the Third Party Partners,
which agreements in existence as of the Effective Date are identified in Exhibit
C and as amended from time to time.

       1.11 "Development and Commercialization Program" shall mean the program
of activities to be conducted by each of Corixa and Medicis during the term of
this Agreement as further described in Exhibit D.

       1.12 "Development Period" shall have the meaning set forth in Section
3.1.

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       1.13 "Development Steering Committee" shall have the meaning set forth in
Section 3.1.

       1.14 "Dissemination" shall have the meaning set forth in Section 12.6(b).

       1.15 "Effective Date" shall mean the date upon which all closing
conditions have been met, as further described in Section 21.

       1.16 "FDA" shall mean the United States Food and Drug Administration and
any successor entity.

       1.17 "First Commercial Sale" shall mean the first [*] sale of a Licensed
Product by Medicis or an Affiliate of Medicis [*] of such Licensed Product in
the Licensed Field in the Territory [*]. Sale of a Licensed Product by Medicis
to an Affiliate of Medicis shall not constitute First Commercial Sale unless
such Affiliate is the end user of the Licensed Product. Notwithstanding the
above, in no event [*], be deemed First Commercial Sale.

       1.18 "Global Steering Committee" shall have the meaning set forth in
Section 3.4.

       1.19 "HPB" shall mean the Canadian Health Protection Board and any
successor entity.

       1.20 "Joint Inventions" shall have the meaning set forth in Section 10.

       1.21 "Joint Patents" shall mean all patent applications and patents that
claim Joint Inventions to the extent that such patent applications and patents
[*]. Included within the definition of Joint Patents are any and all
continuations, continuations-in-part (solely to the extent such continuation(s)
in part contain(s) subject matter referred to in (a), (b), (c), (d) or (e)),
divisions, patents of addition, reissues, renewals and extensions, and any and
all foreign counterparts, of any patent application or patent referred to in
this Section 1.21. Joint Patents shall not include any patent application or
patent that is a patent application or patent within either the Corixa Patents
or the Medicis Patents.

       1.22 "Licensed Field" shall mean treatment or prevention of psoriasis in
humans. The definition of Licensed Field may be expanded from time to time
pursuant to Section 4.2.

       1.23 "Licensed Product" shall mean any product that incorporates any PVAC
Technology, the manufacture, use, sale, import, distribution or other
disposition of which, but for the rights and license granted hereunder, would
infringe a Valid Claim.

       1.24 "Development Fee" shall have the meaning set forth in Section 6.2.

       1.25 "Medicis Inventions" shall have the meaning set forth in Section 10.

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       1.26 "Medicis Know-How" shall mean all technical information, materials
and know-how, including Medicis Inventions, except to the extent published or
included in any patent application, solely or jointly owned or controlled by
Medicis or which becomes owned or controlled by Medicis [*] that relates to the
PVAC Technology and that Medicis has the ability to license, and shall include,
without limitation, all [*].

       1.27 "Medicis Patents" shall mean all patent applications and patents
that claim Medicis Inventions to the extent that such patent applications and
patents [*]. Included with the definition of Medicis Patents are any and all
continuations, continuations-in-part (solely to the extent such continuation(s)
in part contain(s) subject matter referred to in (a), (b), (c) (d) or (e)),
divisions, patents of addition, reissues, renewals and extensions, and any and
all foreign counterparts, of any patent application or patent referred to in
this Section 1.27. Medicis Patents shall not include any patent application or
patent that is a patent application or patent within either the Corixa Patents
or the Joint Patents.

       1.28 "Net Sales" shall mean the [*] amount [*] Medicis, its Affiliates or
either of their Third Party sublicensee(s), as applicable, for the sale or other
disposition to a Third Party of the Licensed Product and less amounts [*], such
amounts determined in accordance with generally accepted accounting principles
applied in a manner consistent with the past practices of Medicis related to
such sale or other disposition, including:

               (a)    [*]

               (b)    [*]

provided, however, that in the event [*].

       1.29 "PVAC Technology" shall mean delipidated and deglycolipidated
Mycobacterium vaccae or [*] and any formulations thereof.

       1.30 "Supply Agreement" shall mean the certain Supply Agreement entered
into by and between Corixa and Medicis, effective as of Effective Date, the form
of which is set forth in Exhibit E.

       1.31 "Territory" shall mean the United States and Canada and each of the
territories, possessions and commonwealths of either of the foregoing.

       1.32 "Third Party(ies)" shall mean any party other than a party to this
Agreement or an Affiliate of a party to this Agreement.

       1.33 "Third Party Partner(s)" shall have the meaning set forth in Section
12.1.

       1.34 "Valid Claim" shall mean a claim of an issued, unexpired patent
included within the Corixa Patents or the Joint Patents that has not been (a)
held invalid or unenforceable by a final decision of a court or governmental
agency of competent jurisdiction, which decision is

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unappealable or was not appealed within the time allowed therefor, or (b)
admitted in writing to be invalid or unenforceable by the holder(s) thereof by
reissue, disclaimer or otherwise.

       1.35 Interpretive Rules. For purposes of this Agreement, except as
otherwise expressly provided herein or unless the context otherwise requires:
(a) defined terms include the plural as well as the singular (and vice versa)
and the use of any gender shall be deemed to include the other gender; (b)
references to "Sections," subsections and "Exhibits," without reference to a
document, are to designated Sections and subsections of, and to designated
Exhibits to, this Agreement; (c) unless otherwise set forth herein, the use of
the term "including" means "including but not limited to"; and (d) the words
"herein," "hereof," "hereunder" and other words of similar import refer to this
Agreement as a whole and not to any particular provision within this Agreement.

2.     DEVELOPMENT AND COMMERCIALIZATION PROGRAM.

       2.1 Commencing on the Effective Date, the parties shall collaborate in
the development and commercialization of the Licensed Product in the Licensed
Field. The program of activities to be conducted by each of Corixa and Medicis
during the term of the Agreement as set forth on Exhibit D to be attached hereto
prior to the Effective Date (the "Development and Commercialization Program"),
which may be reviewed no less often than on an annual basis by the Development
Steering Committee or the Commercialization Steering Committee, as applicable,
and, if necessary and appropriate, amended by the written agreement of the
parties after recommendation by the Development Steering Committee or the
Commercialization Steering Committee, as appropriate, effective upon the next
anniversary of the Effective Date. The Development and Commercialization Program
shall include a development plan setting forth the activities and timelines
currently contemplated by the parties to be performed in developing the Licensed
Products, as well as a description of each party's responsibilities in
connection with the development and commercialization of the Licensed Products.
The timelines included in the Development and Commercialization Program may be
modified from time to time by the Development Steering Committee or the
Commercialization Steering Committee, as appropriate. The parties agree that the
end goal of the Development and Commercialization Program shall be the
expeditious clinical development and regulatory approval of the Licensed
Products and optimization for successful commercialization as necessary for the
import, manufacture, marketing and/or sale thereof in the Territory in the
Licensed Field. No material deviation in the subject matter, scope and timeline
of such Development and Commercialization Program shall be made without the
written agreement of the parties.

       2.2 Subject to the terms and conditions of this Agreement, the parties
acknowledge and agree that nothing in this Agreement shall restrict Corixa's
ability to conduct clinical trials of any nature related to the Licensed
Products using good clinical practice either inside or outside of the Licensed
Field at Corixa's or any of its Third Party Partners' own cost and expense,
provided that [*]. Notwithstanding the foregoing, Corixa shall provide Medicis
access to and permit use of clinical data and regulatory filings controlled by
Corixa related to the Licensed Products in the Licensed Field, and shall also
use reasonable best efforts to [*].

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3.     STEERING COMMITTEES.

       3.1 The parties shall establish a Development Steering Committee (the
"Development Steering Committee") within thirty (30) days following the
Effective Date. The Development Steering Committee shall exist during the period
beginning on the Effective Date and ending on either the date of first
regulatory approval of Licensed Product in the Licensed Field in the Territory
or such later date as mutually agreed by writing by the parties (the
"Development Period"). The Development Steering Committee shall consist of [*]
members, [*] individuals appointed by Corixa and [*] individuals appointed by
Medicis, and shall be chaired by an individual from [*]. The Development
Steering Committee shall be responsible for matters that are reasonably proper
and appropriate for joint consideration by Corixa and Medicis prior to
regulatory approval of the Licensed Product in the Licensed Field in the
Territory, [*]. In addition, the Development Steering Committee shall review the
Development and Commercialization Program at least annually, implement any
mutually agreeable modifications and make recommendations related to possible
Development and Commercialization Program extensions and/or expansions to the
respective senior management teams of each party. Such meetings shall take place
no less frequently than every [*] alternatively in Seattle, Washington and
Scottsdale, Arizona, or at such other location or by videoconference as may be
determined by the Development Steering Committee. All actions by the Development
Steering Committee shall require the approval by [*]. Any disputes that cannot
be resolved by good faith discussion at the Development Steering Committee shall
be subject to dispute resolution in accordance with Section 13.

       3.2 At least [*] prior to the anticipated date of regulatory approval of
a Licensed Product, the parties shall establish a Commercialization Steering
Committee (the "Commercialization Steering Committee"). The Commercialization
Steering Committee shall exist until the expiration or earlier termination of
this Agreement. The Commercialization Steering Committee shall consist of [*]
members, [*] individuals appointed by Medicis and [*] individuals appointed by
Corixa, and shall be chaired by an individual from [*]. The Commercialization
Steering Committee shall be responsible for matters that are reasonably proper
and appropriate for joint consideration by Corixa and Medicis relating to
commercialization of the Licensed Products in the Licensed Field in the
Territory, including, [*]. The Commercialization Steering Committee shall meet
no less frequently than once every [*], alternatively in Seattle, Washington and
Scottsdale, Arizona, or at such other location or by videoconference as may be
determined by the Commercialization Steering Committee, to review and discuss
the commercialization progress and plans with respect to the Licensed Product in
the Licensed Field in the Territory. All actions by the Commercialization
Steering Committee shall require the approval by [*]. Any disputes that cannot
be resolved by good faith discussion at the Commercialization Steering Committee
shall be subject to dispute resolution in accordance with Section 13.

       3.3 In connection with each meeting of the Development Steering
Committee, Corixa shall provide Medicis written reports in a format to be agreed
by Corixa and Medicis on Corixa's progress in performing the Development and
Commercialization Program, including reports on [*]. In addition, in connection
with each meeting of the Development Steering Committee,

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Medicis shall provide Corixa with written reports in a format agreed by Corixa
and Medicis on Medicis' progress in performing the Development and
Commercialization Program, including reports on [*] activities and any other
activities directed to [*]. In conjunction with the meetings of the
Commercialization Steering Committee, Medicis shall provide Corixa with
semi-annual, written summary reports on the progress of commercialization,
including activities and strategic literature related [*]. In addition, in
conjunction with the meetings of the Commercialization Steering Committee,
Corixa shall provide Medicis semi-annual written reports covering [*]. All
reports and data delivered by either party to the other hereunder shall be in
sufficient detail to enable the party receiving such reports and data to
determine the other party's compliance with its diligence obligations under
Section 8. In addition, all reports, data and information provided by either
party to the other hereunder shall be subject to the confidentiality provisions
of Section 12 of this Agreement.

       3.4 Corixa shall use [*] efforts to establish a steering committee to
monitor and coordinate clinical and regulatory matters that are proper and
appropriate for mutual consideration for the Licensed Product in the Licensed
Field worldwide (the "Global Steering Committee"), to be comprised of Corixa,
Medicis, Zenyaku Kogyo Co., Ltd. and any of Corixa's additional Third Party
Partners. The Global Steering Committee shall exist for the primary purpose of
achieving efficient use of all parties' clinical and regulatory resources in
order to obtain regulatory approval throughout the respective territories as
rapidly and efficiently as possible without compromising any partner's existing
rights and to coordinate effort in establishing and protecting intellectual
property rights relating to the Licensed Products. In the event that such Global
Steering Committee is established, it will determine the means by which it will
accomplish such primary purpose and the guidelines by which it will operate
including the term of its existence, which guidelines shall be consistent with
the contractual obligations of the participating parties and applicable law.
Medicis may participate in the Global Steering Committee during the Term to
discuss the results of any clinical and regulatory activity with respect to the
Licensed Product.

4.     LICENSE GRANTS; EXPANSION OF LICENSED FIELD; ADDITIONAL PRODUCT
       OPPORTUNITIES; BENEFITS OF CORIXA THIRD PARTY AGREEMENTS

       4.1    License.

              (a) Subject to the terms and conditions of this Agreement, Corixa
hereby grants to Medicis an exclusive right and license under the Corixa
Patents, the Joint Patents and the Corixa Know-How, together with a right to
grant sublicenses in the Territory, to develop, make, have made, use, have used,
sell, have sold, distribute, offer for sale, import and otherwise dispose of
Licensed Products solely in the Licensed Field in the Territory.

              (b) Prior to the effective date of any sublicense granted by
Medicis hereunder, Medicis shall provide Corixa [*]. Medicis agrees that any
sublicense granted hereunder shall be subject to [*], and that any sublicensee
shall comply with the terms of this Agreement.

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              (c) Subject to the terms and conditions of this Agreement, and
subject to [*], Medicis hereby grants to Corixa [*]. Corixa shall notify Medicis
in writing [*].

              (d) Subject to the terms and conditions of this Agreement and, in
addition, the Supply Agreement, Medicis hereby grants to Corixa an exclusive,
royalty-free and payment-free right and license under the Corixa Patents, the
Joint Patents and the Corixa Know-How to make and have made Licensed Products
solely in the Licensed Field in the Territory.

              (e) During the term of this Agreement, if either Corixa or Medicis
becomes aware of technology relating to the subject matter hereof that is held
or otherwise controlled by a Third Party and, after analysis, believes that such
technology may be useful or necessary to improve or optimize the product (but is
not technology required in order to [*]) for the development and
commercialization of Licensed Products ("Additional Technology"), Corixa or
Medicis, as appropriate, shall present a description of such Additional
Technology, along with a written report including the details of the analysis
that led such party to its belief, to the other party through the Development
Steering Committee or Commercialization Steering Committee, as applicable. The
Development Steering Committee or Commercialization Steering Committee, as
applicable, shall review such description and report and recommend whether a
license to, or an acquisition of, any such Additional Technology should be made.
In the event the Development Steering Committee or Commercialization Steering
Committee, as applicable, recommends that a license to, or acquisition of, any
such Additional Technology should be made, Corixa shall contact and initiate
negotiations with such Third Party regarding the terms and conditions of
agreement to license or acquire rights to such Additional Technology. In the
event that [*] and, provided that [*], Medicis and Corixa shall [*] related
thereto, including but not limited to [*]. Notwithstanding anything to the
contrary in this Section 4.1 (e) but subject to Section 4.4, this Section shall
not limit or otherwise restrict either party in procuring technology for its own
account or for its licensing program with respect to Third Parties.

              (f) During the term of this Agreement, if either Corixa or Medicis
becomes aware of technology relating to the subject matter hereof that is held
or otherwise controlled by a Third Party and technology is required in order to
[*] shall promptly use reasonable best efforts to obtain a license or acquire
rights to such essential technology, with no additional cost or obligation to
[*].

       4.2 Expansion of the Licensed Field. In the event that Corixa from time
to time during the term of this Agreement obtains or otherwise has the rights
necessary for Corixa to grant to Medicis rights and licenses related to PVAC
Technology with respect to [*], Corixa shall provide Medicis prompt written
notice thereof. Subject to Section 4.1(f), to the extent that such rights
concern [*], such rights, upon [*] written notice [*], together with [*] of [*]
related to obtaining such rights, shall be included within [*]. To the extent
that such rights concern [*], Corixa and Medicis, upon Medicis' written notice
to Corixa, shall negotiate promptly and in good faith with respect to terms and
conditions under which such rights may be included within the Licensed Field and
the rights and licenses

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granted to Medicis hereunder, including [*]. In the event that Corixa and
Medicis have not agreed upon the terms and conditions under which rights with
respect to any [*] may be included within the Licensed Field and the rights and
licenses granted to Medicis hereunder within [*] following the date of Medicis'
written notice to Corixa, both parties shall designate whether or not such
product would be deemed a product that [*]. In the event that the parties agree
that the opportunity is not a product that [*], Corixa shall [*]. In the event
that the parties agree that the opportunity is a product that [*], Corixa may
[*]. Notwithstanding the foregoing, Corixa agrees that any product resulting
from such opportunity will be designed to [*].

       4.3 Opportunities in the Licensed Field Not Related to PVAC Technology.
In the event that either party, at any time within [*], believes that it has
additional product research, development and/or commercialization opportunities
for additional product(s) potentially efficacious in the Licensed Field, [*],
such party shall present such opportunity to the Development Steering Committee
or Commercialization Steering Committee, as applicable. In the event the
Development Steering Committee or Commercialization Steering Committee, as
applicable, determines that any such opportunity should be pursued, the parties
shall discuss in good faith [*]. In the event that one party agrees [*], such
party may [*].

       4.4 Restrictions on the Parties. In the event the Development Steering
Committee or Commercialization Steering Committee, or Medicis or Corixa as
applicable, determines not to pursue any additional product opportunity
presented pursuant to Section 4.1(e), 4.2 or 4.3, the party that presented such
opportunity hereunder may pursue such opportunity on its own or with a Third
Party so long as such opportunity is [*]. For purposes of this Section 4.3, [*].
In addition, even if the party pursuing such opportunity under this Section 4.4
[*], such party agrees that [*]. In the event that there is a dispute [*], the
parties will hire an independent third party mutually acceptable to both parties
[*].

       4.5 Acknowledgment of Third Party Covenants. Medicis acknowledges that
the Licensed Products will incorporate technology that has been licensed to
Corixa pursuant to the Corixa Third Party Licensor Agreements, and that the
licenses, warranties, representations, and grants made by Corixa under this
Agreement are subject to the terms and conditions of the Corixa Third Party
Licensor Agreements as in effect on the Execution Date and as may be amended
from time to time in accordance with the terms and conditions of this Agreement.
[*]

5.     PAYMENTS.

       Medicis shall make the following payments to Corixa under this Agreement
in U.S. dollars by wire transfer of immediately available funds:

       5.1 Up Front Payment Medicis shall pay to Corixa [*], payable upon the
Effective Date.

       5.2 Research and Development Funding. Medicis shall pay to Corixa
research and development funding payments in the following amounts on the dates
set forth below:

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<TABLE>
<CAPTION>
-------------------------------------------------------------------------------
                   PAYMENT DATE                               PAYMENT
-------------------------------------------------------------------------------
<S>                                                        <C>
(a) The Effective Date                                          [*]
-------------------------------------------------------------------------------
[*]                                                             [*]
-------------------------------------------------------------------------------
</TABLE>

       The payment amounts required to be made pursuant to Section 5.1 shall be
[*] paid directly to Corixa when due and payable [*].

       5.3 Milestone Payments. In addition to the amounts payable pursuant to
Sections 5.1 and 5.2 above, Medicis also agrees to pay Corixa the following
milestone payments within [*] following achievement of such milestone:

<TABLE>
<CAPTION>
-------------------------------------------------------------------------------
    (a)     DEVELOPMENT MILESTONE                                     PAYMENT
-------------------------------------------------------------------------------
<S>         <C>                                                       <C>
    (i)     [*]                                                         [*]
-------------------------------------------------------------------------------
    (ii)    [*]                                                         [*]
-------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
-------------------------------------------------------------------------------
    (b)     COMMERCIALIZATION MILESTONE                               PAYMENT
-------------------------------------------------------------------------------
<S>         <C>                                                       <C>
    (i)     [*]                                                         [*]
-------------------------------------------------------------------------------
    (ii)    [*]                                                         [*]
-------------------------------------------------------------------------------
    (iii)   [*]                                                         [*]
-------------------------------------------------------------------------------
</TABLE>

The payments required to be made pursuant to this Section 5.3 shall be [*]. The
payment pursuant to Section 5.3 (a)(i) may be [*].

6.     ROYALTY AND OTHER PAYMENTS.

       6.1 Royalties for Licensed Product. (a) Subject to the terms and
conditions of this Agreement, Medicis shall pay to Corixa a royalty of [*]. Such
royalty is [*] and in the event of a [*]. In the event that during the Term, the
Licensed Products are only covered by Joint Patents and no Corixa Patents, the
royalty during such period shall be [*].

              (a) In the event of the commercial sale in the Territory of one
(1) or more product(s) containing [*], which product(s) has been [*], then the
royalty rate in this Section 6.1 [*] shall be [*]. In the event [*] shall have
the right to refer the matter to arbitration within [*] of written notice [*].

              (b) In the event of the commercial sale in the Territory of one
(1) or more product(s) containing [*], then the royalty rate in this Section 6.1
[*] shall be [*]. In the event [*] shall have the right to refer the matter to
arbitration [*].

              (c) Notwithstanding anything in this Agreement to the contrary,
the royalty reductions set forth in this Section 6.1 shall not [*].

       6.2 Continuing Research and Development Fee. Subject to the terms and
conditions of this Agreement, Medicis shall pay to Corixa a fixed fee, set at
[*].

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       6.3 Currency. All amounts payable to Corixa under this Agreement shall be
payable in United States dollars by wire transfer of immediately available funds
to a bank account designated by Corixa. Any amounts invoiced and any amounts
deducted in the determination of Net Sales during any calendar quarter
corresponding to Canadian Dollars shall be translated at the end of such quarter
into U.S. Dollars by using an average rate of exchange computed using the
closing rate of exchange quoted by the Wall Street Journal (western edition) for
purchase of U.S. Dollars with Canadian Dollars on the last day of such quarter
plus the closing rate of exchange quoted by the Wall Street Journal (western
edition) for purchase of U.S. Dollars with Canadian Dollars on the last day of
the prior quarter and dividing by two (2).

       6.4 Withholding Tax. Medicis will make all payments made by Medicis under
this Agreement after deduction of withholding tax (if any) imposed upon such
payment. Medicis shall use reasonable commercial efforts to minimize such
withholding taxes. If reasonably requested by Corixa, Medicis shall cooperate
with Corixa regarding the characterization of payments made hereunder so that
advantage may be taken of any and all benefits under any Canadian-US tax treaty
to the extent that such cooperation does not materially affect Medicis.

7.     REPORTS, PAYMENTS AND ACCOUNTING.

       7.1    Payments and Reports.

              (a) During the term of this Agreement, Medicis agrees to make
quarterly written reports (in a format set forth in Exhibit F), and the payments
set forth in Section 6 to Corixa within [*] days after the close of each
calendar quarter during the term of this Agreement. These reports shall show for
such calendar quarter sales by Medicis, its Affiliates and sublicensees of
Licensed Product, details of [*]. Concurrently with the making of each such
report, Medicis shall make payment to Corixa of (i) amounts payable under
Section 6 for the period covered by such report and (ii) all other amounts
accrued under this Agreement that have not been previously reimbursed as
required, unless otherwise provided hereunder.

              (b) During the term of this Agreement, Corixa agrees to submit to
Medicis a detailed statement of account, together with copies of invoices
received by Corixa, within [*] after the close of each calendar quarter for the
[*] costs actually incurred by Corixa as a result of services provided to Corixa
by professionals in connection with the filing, prosecution and maintenance of
the Corixa Patents and Joint Patents in the Licensed Field in the Territory,
including the costs and expenses of patent filings, during the term of this
Agreement as set forth in Section 11.1.

       7.2 Termination Report. Medicis also agrees to make a written report (in
a format, if any, reasonably specified by Corixa) [*] after the date on which
Medicis, its Affiliates or sublicensees sell the last Licensed Product stating
in such report the same information required for quarterly reports provided
under Section 7.1 hereof.

       7.3 Accounting. Medicis agrees to keep clear, accurate and complete
records for a period of at least [*] for each reporting period in which sales of
Licensed Product occur showing

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sales and disposition thereof in sufficient detail to determine amounts payable
pursuant to Section 6 hereof. Medicis further agrees to permit its books and
records relating solely to the Licensed Products to be examined from time to
time (but not more than once a year) by an independent accounting firm selected
and paid by Corixa and reasonably satisfactory to Medicis. Such examination
shall occur only on reasonable notice clearly stating the audit period to be
examined by or on behalf of Corixa during regular business hours during the term
of this Agreement and for [*] thereafter, provided, however, that such
examination shall not (i) be of records for more than the prior [*], (ii) take
place more often than once a year and (iii) cover any records that date prior to
the date of the last examination, or for longer than the period during which
Medicis is required to keep such records and provided further that such
accountants shall report to Corixa only as to the accuracy of the royalty
statements and payments. Copies of such reports shall be supplied to Medicis. In
the event that the report demonstrates that Medicis has underpaid Corixa,
Medicis shall pay to Corixa the amount of such underpayment within [*] after
receipt of a written request of Corixa and to the extent such underpayment is
more than [*] of the royalty payments otherwise due for the audited period,
Medicis shall reimburse Corixa for the reasonable expense of the audit or
dispute such claim of underpayment and if necessary, initiate dispute resolution
in accordance with Section 13 of this Agreement. In the event that the report
demonstrates that Medicis has overpaid Corixa, Corixa shall pay to Medicis the
amount of such overpayment within [*] after receipt of a written request of
Medicis.

       7.4 Confidentiality of Reports. Each party agrees that the information
set forth in (i) the reports required by Sections 7.1 and 7.2 and (ii) the
records subject to examination under Section 7.3, shall be subject to Section 12
hereof and maintained in confidence by the receiving party and any independent
accounting firm selected by such party, shall not be used by such party or such
accounting firm for any purpose other than verification of the performance by
the other party of its obligations hereunder, and shall not be disclosed by the
receiving party or such accounting firm to any other person except for purposes
of enforcing this Agreement.

       7.5 Late Payments. Any payment not paid hereunder when due shall bear
interest from such due date at the rate of [*].

       7.6 R&D Credit. Medicis shall have the right to claim the R&D credit for
[*].

8.     COMMERCIAL DEVELOPMENT.

       8.1 Diligence by Corixa. At Corixa's sole expense, but subject to
Medicis' payment obligations under Section 5 and 6, Corixa shall use reasonable
best efforts to (a) diligently undertake and complete clinical development of
the Licensed Product, (b) obtain regulatory approval of the Licensed Product
from the FDA and HPB and (c) manufacture the Licensed Product in the Territory
in accordance with the Development and Commercialization Program, including the
timelines set forth therein. [*]:

       [*]

       8.2 Diligence by Medicis. Medicis, [*] shall use [*] efforts to
diligently undertake market development, commercial launch and sales and
marketing activity for Licensed Product

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in the Licensed Field in the Territory in accordance with the Development and
Commercialization Program, including the timelines set forth therein. Medicis
shall use [*] efforts to [*].

       8.3 Level of Diligence to be Used by Medicis and Corixa. Each party shall
use efforts to develop and commercialize Licensed Product in the Territory
equivalent to those efforts applied by such party to its own
internally-developed priority products.

9.     SUPPLY.

       Corixa shall provide Medicis with Licensed Product pursuant to the terms
and conditions of a Supply Agreement in the form attached hereto as Exhibit E
(the "Supply Agreement") and in compliance with all applicable foreign, federal,
state or local laws and regulations. Medicis shall use all materials provided to
Medicis by Corixa hereunder or under the Supply Agreement in compliance with all
applicable foreign, federal, state or local laws and regulations.

10.    INVENTIONS.

       Any and all ideas, inventions, discoveries, developments, designs, trade
secrets, improvements, know-how, processes, procedures, techniques, formulae,
computer programs, drawings and technology(ies), whether or not patentable,
made, conceived, developed or reduced to practice solely by employees or agents
of Corixa or jointly by employees or agents of Corixa and a Third Party or
Corixa Affiliate other than an employee or agent of Medicis and which arise from
the performance of the Development and Commercialization Program shall be owned
by Corixa (collectively, "Corixa Inventions"). Any and all ideas, inventions,
discoveries, developments, designs, trade secrets, improvements, know-how,
processes, procedures, techniques, formulae, computer programs, drawings and
technology(ies), whether or not patentable, made, conceived, developed or
reduced to practice jointly by employees or agents of Corixa and Medicis and
which arise from the performance of the Development and Commercialization
Program shall be jointly owned by Corixa and Medicis and treated as joint
inventions in accordance with United States patent laws (collectively, "Joint
Inventions"). Any and all ideas, inventions, discoveries, developments, designs,
trade secrets, improvements, know-how, processes, procedures, techniques,
formulae, computer programs, drawings and technology(ies), whether or not
patentable, made, conceived, developed or reduced to practice solely by
employees or agents of Medicis or jointly by employees or agents of Medicis and
a Third Party or Corixa Affiliate other than an employee or agent of Corixa and
which arise from the performance of the Development and Commercialization
Program shall be owned by Medicis (collectively, "Medicis Inventions"). Except
as otherwise set forth in this Agreement, Medicis and Corixa shall retain their
respective unrestricted rights to develop, make, have made, use, have used,
sell, have sold, distribute, offer for sale, import and otherwise dispose of all
such inventions and discoveries that are owned by them.

11.    PATENTS; PROSECUTION AND LITIGATION.

11.1 Subject to the terms and conditions of this Agreement, Corixa shall control
and be responsible for protecting, preparing, filing, prosecuting and
maintaining all Corixa Patents and

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Joint Patents as provided in this Section 11 and shall do so using [*] efforts
and in a timely manner, provided that Medicis shall have an opportunity to
review and comment on all such matters. With respect to Joint Patents, patent
counsel reasonably acceptable to Medicis shall be utilized. Corixa shall
promptly disclose in writing to Medicis the complete texts of all Corixa Patents
and Joint Patents as well as all information received concerning any
interference, opposition, re-examination, reissue, revocation, nullification or
any official proceeding involving any patent licensed herein. Corixa agrees to
keep Medicis promptly and fully informed of the course of patent prosecution or
other proceedings including by providing Medicis with copies of substantive
communications, search reports and Third Party observations submitted to or
received from patent offices. Medicis shall have the right to review all such
pending applications, patents, substantive communications and other proceedings
and make recommendations to Corixa concerning them and their conduct in the
Territory. Corixa shall consider in good faith Medicis' recommendations relating
to such pending applications, patents, substantive communications and other
proceedings and, with respect to Joint Patents, shall adopt and otherwise
incorporate all such reasonable recommendations. Corixa and Medicis each shall
treat all information disclosed to it by the other party under this Section 11
in accordance with Section 12. [*] in connection with the filing, prosecution
and maintenance of the Corixa Patents and Joint Patents in the Licensed Field in
the Territory during the term of this Agreement, and if Corixa determines [*].
All expenses to be paid or reimbursed [*] pursuant to this Section 11 shall be
obligations that are separate and apart from other payment obligations described
in this Agreement and shall be invoiced and paid separately.

       11.2 In the event Corixa decides to abandon any patent (including Corixa
Patents) covered by this Agreement, [*].

       11.3 (a) In the event of the initiation of any suit by a Third Party
against Corixa, Medicis or any Affiliate of either party for infringement of
patent rights held by such Third Party or with respect to allegations of
misappropriation of such Third Party's trade secret information, in either case,
either with respect to the exercise of rights within the subject matter of the
Corixa Patents or the Joint Patents in the Licensed Field in the Territory, or
with respect to the exercise of rights solely within the subject matter of
either the Corixa Patents or the Joint Patents and the Medicis Patents in the
Licensed Field in the Territory, the party sued shall promptly notify the other
party in writing. Subject to any right to control the defense of such action
retained by Corixa's Third Party licensor with respect to the Corixa Patents,
Corixa shall have the first right to defend such suit at its own expense.
Medicis shall assist and cooperate with Corixa, and [*], in any such litigation,
[*]. In the event that within ninety (90) days following the initiation of
such a suit, Corixa has not taken any action regarding such suit, Medicis shall
have the right, but not the obligation, to control such defense at [*]
expense. In any such action controlled by Medicis, Corixa shall cooperate, and
shall [*].

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              (b) In the event of the initiation of any suit by a Third Party
against Corixa, Medicis or any Affiliate of either for infringement of patent
rights held by such Third Party or with respect to allegations of
misappropriation of such Third Party's trade secret information, in either case,
with respect to the exercise of rights solely within the subject matter of the
Medicis Patents in the Licensed Field in the Territory, the party sued shall
promptly notify the other party in writing. Medicis shall have the first right
to defend such suit at its own expense. Corixa shall assist and cooperate with
Medicis in any such litigation, such cooperation to be at the expense of
[*]. In the event that within ninety (90) days following the initiation of
such a suit, Medicis has not taken any action regarding such suit, Corixa shall
have the right, but not the obligation, to control such defense at [*]
expense and Medicis shall cooperate with Corixa in connection therewith at
[*] expense. [*].

       11.4 (a) In the event that Corixa or Medicis becomes aware of actual or
threatened infringement of a patent covered by this Agreement either with
respect to the Corixa Patents or the Joint Patents in the Licensed Field in the
Territory, or with respect to either the Corixa Patents or the Joint Patents and
the Medicis Patents in the Licensed Field in the Territory, or with respect to
misappropriation of trade secret information owned or controlled by Corixa or
jointly by Corixa and Medicis, that party shall promptly notify the other party
in writing thereof. In connection with any such actual or threatened
infringement or misappropriation in the Territory, subject to any right to
control such action retained by Corixa's Third Party licensor with respect to
the Corixa Patents, Corixa shall have the first right but not the obligation to
bring an infringement or misappropriation action against any alleged infringer
at its sole cost and expense. Medicis shall assist and cooperate with Corixa,
and [*] in any such litigation, [*]. In the event that within ninety (90)
days following Corixa becoming aware of such actual or threatened infringement
or misappropriation, Corixa has not taken any action regarding such actual or
threatened infringement or misappropriation, Medicis shall have the right to
control any such action against such actual or threatened infringement or
misappropriation at Medicis' expense. In any such action controlled by Medicis,
Corixa shall cooperate, and shall [*].

              (b) In the event that Corixa or Medicis becomes aware of actual or
threatened infringement of a patent covered by this Agreement solely with
respect to Medicis Patents in the Licensed Field in the Territory, or with
respect to allegations of misappropriation of trade secret information owned or
controlled by Medicis other than jointly with Corixa, that party shall promptly
notify the other party in writing thereof. In connection with any such actual or
threatened infringement or misappropriation in the Territory, Medicis shall have
the first right but not the obligation to bring an infringement or
misappropriation action against any alleged infringer at its sole cost and
expense. Corixa shall assist and cooperate with Medicis in any such litigation,
such cooperation to be at the expense of [*]. In the event that within
ninety (90) days following Medicis becoming aware of such actual or

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threatened infringement or misappropriation, Medicis has not taken any action
regarding such actual or threatened infringement, Corixa shall have the right to
control any such action against such actual or threatened infringement or
misappropriation at [*] expense. [*].

              (c) In the event that Corixa or Medicis becomes aware of actual or
threatened infringement of a patent covered by this Agreement with respect to
the Licensed Product in the Licensed Field, or with respect to allegations of
misappropriation of trade secret information, outside the Territory, that party
shall promptly notify the other party in writing thereof. Corixa or Corixa's
Third Party licensor, if applicable, shall have the first right but not the
obligation to bring an infringement or misappropriation action with respect to
the foregoing at such party's sole cost and expense, provided, however, that in
connection with any such actual or threatened infringement of Medicis Patents or
misappropriation of trade secret information outside the Territory, Medicis
shall have the first right but not the obligation to bring an infringement or
misappropriation action at its sole cost and expense. The party conducting such
action shall have full control over its conduct, provided that [*]. Corixa shall
assist and cooperate with Medicis in any such action at [*]. Medicis shall
assist and cooperate with Corixa or Corixa's Third Party licensor, if
applicable, in any action controlled by Corixa's or Corixa's Third Party
licensor, if applicable, at such controlling party's request and expense.
Notwithstanding the foregoing, in the event any actual or threatened
infringement of any Medicis Patent(s) or misappropriation of trade secret
information is [*].

       11.5 Any recovery with respect to the Corixa Patents or the Joint Patents
that are the subject of an action pursuant to Section 11.3 or Section 11.4, in
an amount in excess of expenses and related to an action involving activities in
the Territory, shall be first applied to [*].

       11.6 The parties shall keep one another informed of the status of their
respective activities regarding any litigation or settlement thereof concerning
the Licensed Product. Each party shall execute all necessary and proper
documents and take such actions as shall be appropriate to allow the other
party(ies) to institute, prosecute and/or defend such actions. Notwithstanding
anything herein to the contrary, Corixa and Medicis may determine to cooperate
in connection with any action pursuant to Sections 11.3 or 11.4 and share the
costs and expenses in connection therewith in a mutually agreed manner.

       11.7 CORIXA MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED,
OTHER THAN THOSE EXPRESSLY SET FORTH IN SECTION 17 BELOW INCLUDING WITHOUT
LIMITATION ANY WARRANTY OF NONINFRINGEMENT, PATENTABILITY, MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE.

       11.8 MEDICIS MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED,
OTHER THAN THOSE EXPRESSLY SET FORTH IN SECTION 17 BELOW

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INCLUDING WITHOUT LIMITATION ANY WARRANTY OF NONINFRINGEMENT, PATENTABILITY,
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

12. CONFIDENTIALITY; PUBLICITY; PUBLICATIONS.

       12.1 Disclosure of Inventions. During the term of this Agreement, Corixa
shall promptly disclose, and shall use [*] efforts to cause any Third Party(ies)
that are Corixa's partners with which Corixa has written agreements for the
development and commercialization of Licensed Product (the "Third Party
Partners") to promptly disclose, to Medicis and/or supply Medicis in a timely
fashion with all documented Corixa Know-How, all Corixa Patents and all relevant
patent applications filed and/or controlled by Corixa or the Third Party
Partner(s) and all inventions controlled by Corixa or the Third Party Partner(s)
related to the Licensed Product in the Licensed Field, all such information to
be deemed Confidential Information. During the term of this Agreement, Medicis
shall promptly disclose to Corixa and/or supply Corixa in a timely fashion with
all documented Medicis Know-How, Medicis Patents and all relevant patent
applications filed and/or controlled by Medicis and all inventions controlled by
Medicis related to the Licensed Product in the Licensed Field in the Territory,
all such information to be deemed Confidential Information. In addition, each
party shall provide the other party with all information that is reasonably
necessary or useful for achieving the goals of the Development and
Commercialization Program.

       12.2 Information to Governmental Agencies; Adverse Drug Events. The
parties recognize that each may be required to submit information and file
reports to various governmental agencies on compounds under clinical
investigation, compounds proposed for marketing as drugs, or marketed drugs. In
this regard, information must be submitted at the time of initial filing for
investigational use in humans and at the time of a request for market approval
of a new drug. In addition, supplemental information must be provided on
compounds at periodic intervals and adverse drug experiences must be reported at
more frequent intervals depending on the severity of the experience.
Consequently, each party agrees to:

              (a) provide to the other party for initial and/or periodic
submission to government agencies significant information on the Licensed
Product from preclinical laboratory, animal toxicology and pharmacology studies,
as well as adverse drug experience reports from clinical trials and commercial
experiences with the Licensed Product;

              (b) in connection with investigational use of the Licensed
Product, report to the other party within five (5) business days of the initial
receipt of a report of any unexpected Grade 3 or 4 adverse event or serious
adverse event with the Licensed Product or concurrently with the reporting of
such experience to a regulatory agency, if sooner than five (5) business days,
or sooner if required for any party to comply with regulatory requirements; and

              (c) in connection with commercial use of the Licensed Product,
report to the other party within five (5) business days of the initial receipt
of a report of any adverse experience with the Licensed Product that is serious
and unexpected or sooner if required for any party to comply with regulatory
requirements. Serious adverse experiences mean any experience

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that suggests a significant hazard, contraindication sideeffect or precaution,
or any experience that is fatal or life-threatening, is permanently disabling,
requires or prolongs inpatient hospitalization, or is a congenital anomaly,
cancer or overdose. An unexpected adverse experience is one not identified in
nature, specificity, severity or frequency in the current investigator brochure
or the United States labeling for the Licensed Product. Each party also agrees
that if it contracts with a third party for research to be performed by such
third party on the Licensed Product, that party agrees to require such third
party to report to the contracting party the information set forth in
subparagraphs (a), (b) and (c) above, and such contracting party shall provide
this information to the other party.

       12.3 Confidential Information. During the term of this Agreement and for
[*] thereafter, neither Corixa nor Medicis shall use or reveal or disclose to
any Third Party any Confidential Information of the other party, without first
obtaining the written consent of the other party, except as may be otherwise
provided herein. "Confidential Information" shall mean any and all proprietary
or confidential information of a party disclosed to the other party and all
Corixa Know-How and Medicis Know-How. Obligations of nonuse and confidentiality
set forth herein shall not apply to such Confidential Information that is or
becomes a matter of public knowledge, or is already in the possession of the
receiving party, or is disclosed to the receiving party by a Third Party having
the right to do so, or is subsequently and independently developed by employees
of the receiving party or Affiliates thereof who had no knowledge of the
confidential information disclosed, or is required to be disclosed by or is
necessary to comply with any law or regulation, including those related to
governmental authorizations in the Licensed Field in the Territory, or necessary
to file or prosecute patent applications concerning the PVAC Technology or the
Licensed Products in the Licensed Field in the Territory, or to carry out any
litigation concerning the PVAC Technology or the Licensed Product, provided that
the receiving party only discloses that portion of Confidential Information
required or necessary and uses reasonable best efforts to provide reasonable
notice to allow the disclosing party to object to or seek protection for the
disclosure, in each case as demonstrated by the receiving party to the
reasonable satisfaction of the disclosing party. The parties shall take
reasonable measures to assure that no unauthorized use or disclosure is made by
others to whom access to such information is granted.

       12.4 Permitted Disclosures. Nothing herein shall be construed as
preventing Medicis from disclosing any Confidential Information received from
Corixa to any Medicis Affiliate, or sublicensee or distributor of Medicis,
provided such Affiliate is bound by similar confidentiality and nonuse
obligations and such sublicensee or distributor has undertaken in writing a
similar obligation of confidentiality and nonuse with respect to the
Confidential Information, with Corixa stated as a third-party beneficiary
thereof. In addition, nothing herein shall be construed as preventing Corixa
from disclosing any Confidential Information received from Medicis to any Corixa
Affiliate, or sublicensee or distributor of Corixa, provided such Affiliate is
bound by similar confidentiality and nonuse obligations and such sublicensee or
distributor has undertaken in writing a similar obligation of confidentiality
and nonuse with respect to the Confidential Information, with Medicis stated as
a third-party beneficiary thereof.

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       12.5 Bankruptcy Procedures. All Confidential Information disclosed by one
party to the other shall remain the intellectual property of the disclosing
party. In the event that a court or other legal or administrative tribunal,
directly or through an appointed master, trustee or receiver, assumes partial or
complete control over the assets of a party to this Agreement based on the
insolvency or bankruptcy of or any other similar insolvency event with respect
to such party, the bankrupt or insolvent party shall promptly notify the court
or other tribunal (i) that Confidential Information received from the other
party under this Agreement remains the property of the other party and (ii) of
the confidentiality obligations under this Agreement. In addition, the bankrupt
or insolvent party shall, to the extent permitted by law, take all steps
necessary or desirable to maintain the confidentiality of the other party's
Confidential Information and to insure that the court, other tribunal or
appointee maintains such Confidential Information in confidence in accordance
with the terms of this Agreement.

       12.6 Publicity.

              (a) The parties to this Agreement shall agree upon a joint
disclosure of the nature, general terms and other agreed aspects of the
Agreement in a joint press release. The wording of any press release must be
agreed by both parties in advance of its release. Notwithstanding the foregoing,
each party shall have the right to issue press releases, immediately and without
prior consent of the other party, that disclose any information required by the
rules and regulations of the Securities and Exchange Commission or similar
federal, state or foreign authorities, as determined in good faith by
independent legal counsel to the disclosing party; provided that, the disclosing
party shall notify the other party of any such disclosure and the disclosing
party shall seek confidential treatment of any information that the other party
reasonably requests be maintained as confidential.

              (b) Neither party shall publish or provide public disclosure of
Confidential Information or Inventions (a "Dissemination") without at least [*]
prior written notice of such planned publication or disclosure sent to the other
party. In the event any such Dissemination is determined by the other party to
be detrimental to its intellectual property position, the disseminating party
shall delay such publication for a period sufficient, but in no event greater
than an additional [*], to allow the other party to take the steps necessary to
protect such intellectual property, including the filing of any patent
applications and deletion of the other party's Confidential Information.
Notwithstanding the foregoing, either party shall have the right to disclose
information immediately and without prior consent of the other party if such
disclosure is required by the rules and regulations of the Securities and
Exchange Commission or similar federal or state authority, as determined in good
faith by independent legal counsel to the disclosing party, provided that the
disclosing party shall notify the other party of any such disclosure and the
disclosing party shall seek confidential treatment of any information that the
other party reasonably requests be maintained as confidential.

13. GOVERNING LAW; ARBITRATION.

        This Agreement shall be governed by the laws of the state of Delaware
without regard to its or any other jurisdiction's conflicts of law principles.
Prior to engaging in any formal dispute

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resolution with respect to any dispute, controversy or claim arising out of or
in relation to this Agreement or the breach, termination or invalidity thereof
(each, a "Dispute"), the most senior executive officer having the right to
represent the respective parties shall attempt for a period of not less than
thirty (30) days to resolve such Dispute. Any Dispute that cannot be settled
amicably by agreement of the parties pursuant to the preceding sentence, shall
be finally settled by arbitration in accordance with the arbitration rules of
the American Arbitration Association, then in force, by one or more arbitrators
appointed in accordance with said rules, provided that the appointed arbitrators
shall have appropriate experience in the biopharmaceutical industry or
pharmaceutical dermatological marketing and sales experience. The place of
arbitration shall be Seattle, Washington if arbitration is initiated by Medicis
and Scottsdale, Arizona if initiated by Corixa. The authority of the appointed
arbitrators shall be limited to the application of the laws of the state of
Delaware to the facts of the particular Dispute before the appointed arbitrators
without regard to any other matter or fact not directly related to such Dispute
including, for example, any amounts paid or payable pursuant to any provision of
this Agreement other than the payment or non-payment of amounts that are the
subject of such Dispute pursuant to the terms and conditions of a particular
provision of this Agreement. The award rendered shall be final and binding upon
both parties. The judgment rendered by the arbitrator(s) shall include costs of
arbitration, reasonable attorneys' fees and reasonable costs for any expert and
other witnesses. Nothing in this Agreement shall be deemed as preventing either
party from seeking injunctive relief (or any other provisional remedy) from any
court having jurisdiction over the parties and the subject matter of the dispute
as necessary to protect either party's name, proprietary information, trade
secrets, know-how or any other proprietary rights. Judgment upon the award may
be entered in any court having jurisdiction, or application may be made to such
court for judicial acceptance of the award and/or an order of enforcement as the
case may be. All costs and expenses of the party that prevails in any
arbitration conducted in accordance with this Section 13 shall be paid by the
non-prevailing party. Notwithstanding anything to the contrary contained herein,
matters pertaining to the scope, validity and/or enforceability of patents shall
be governed by applicable federal law and any disputes relating thereto shall
not be subject to arbitration in accordance with this Section 13.

14. MISCELLANEOUS.

       14.1 Trademarks. Medicis shall own all United States and Canadian
trademark(s) related to the Licensed Product in the Licensed Field, as may be
expanded, ("Trademarks"). Medicis shall consult with Corixa prior to selecting
such trademark(s) and shall consider in good faith Corixa's comments related
thereto. Notwithstanding the foregoing, Medicis shall mark all Licensed Product
commercialized by it with issued patent numbers identified in writing by Corixa
and using Corixa's "Powered by Corixa" trademark and logo, in each case in
commercially reasonable compliance with Corixa's patent marking and trademark
usage policies as provided to Medicis. In the event that this Agreement is
terminated by Corixa as a result of Medicis' uncured material breach of this
Agreement, all trademarks owned or controlled by Medicis relating solely to
Licensed Products shall be licensed promptly to Corixa in accordance with
Section 19.5.

       14.2 Force Majeure. If the performance by either party of any obligation
under this Agreement, is prevented, restricted, interfered with or delayed by
reason of acts of God; acts, regulations, orders, decrees or laws of any
government or agency thereof that are not due to or

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caused by any action or inaction of the party claiming the benefit of force
majeure where such action or inaction is in violation of such party's
obligations under the Agreement or applicable laws; war; civil commotion; damage
to or destruction of facilities; labor disturbances; epidemic; and failure of
public utilities or common carriers, the party so affected shall, upon giving
written notice to the other party, be excused from such prevention, restriction,
interference or delay, provided that the affected party shall use its reasonable
best efforts to avoid or remove such causes of nonperformance and shall continue
performance with the utmost dispatch whenever such causes are removed. When such
circumstances arise, the parties shall discuss what, if any, modifications of
the terms of this Agreement may be required in order to arrive at an equitable
solution

       14.3 Severability.

              (a) In the event any portion of this Agreement shall be held
illegal, void or ineffective, such portion shall be severed from this Agreement
and the remaining portions hereof shall remain in full force and effect,
provided that no such severance shall be effective if it materially changes the
economic benefit of this Agreement to either Corixa or Medicis. In the event
that any portion of this Agreement is held illegal, void or ineffective and
severance of such portion would materially change the economic benefit of this
Agreement to either Corixa or Medicis, Corixa and Medicis shall modify such
portion in accordance with Section 14.4 to obtain a legal, valid and effective
portion and provide an economic benefit to Corixa and Medicis that most nearly
effects Corixa's and Medicis' intent in entering into this Agreement.

              (b) If any of the terms or provisions of this Agreement are in
conflict with any applicable statute or rule of law, then such terms or
provisions shall be deemed inoperative to the extent that they may conflict
therewith and shall be deemed to be modified to conform with such statute or
rule of law.

       14.4 Entire Agreement. This Agreement, including all Exhibits hereto,
entered into as of the date first written above, together with the Supply
Agreement, constitutes the entire agreement between the parties relating to the
subject matter hereof and supersedes all previous writings and understandings
except that with respect to the period before the Execution Date of this
Agreement, confidentiality issues between the parties shall be governed by the
Confidential Information and Non Disclosure Agreement dated as of July 23, 1999,
as amended June 21, 2000 (the "Confidentiality Agreement"). No terms or
provisions of this Agreement shall be varied or modified by any prior or
subsequent statement, conduct or act of either of the parties, except that the
parties may mutually amend this Agreement by written instruments specifically
referring to and executed in the same manner as this Agreement.

15. NOTICES.

        15.1 Any notice required or permitted under this Agreement shall be
deemed given if delivered by facsimile transmission (receipt verified) and at
least one other means selected from the group consisting of (i) personally, (ii)
by registered or certified mail (return receipt requested), postage prepaid, or
(iii) sent by express courier service (receipt verified), to the following
addresses of the parties:

                                       21
<PAGE>   23

               If to Corixa:

               Corixa Corporation
               1124 Columbia Street, Suite 200
               Seattle, WA  98104-2040
               Attention:  Chief Operating Officer
               with a copy to General Counsel
               Telephone:  (206) 754-5711
               Facsimile:  (206) 754-5994

               If to Medicis:

               Medicis Pharmaceutical Corporation
               8125 North Hayden Road
               Scottsdale, AZ  85258-2463
               Attention:  Chief Executive Officer
               with a copy to General Counsel
               Telephone:  (602) 808-8800
               Facsimile:  (602) 808-0822

       15.2 Any notice required or permitted to be given pursuant to this
Agreement shall be effective upon actual or verified receipt by Corixa or
Medicis, as the case may be.

16. ASSIGNMENT.

       Neither this Agreement nor any interest hereunder shall be assignable by
either party without the written consent of the other, provided, however, that
either party may assign this Agreement to any of such party's Affiliates or to
any corporation or other entity with which such party may merge or consolidate,
or to any corporation or other entity to which such party may transfer all of
such party's assets, without obtaining the consent of the other party. Transfer
in contravention of this Section 16 shall be considered a material breach of
this Agreement pursuant to Section 18.2 below. Subject to other provisions of
this Section 16, all rights and obligations under this Agreement shall be
binding upon and inure to the benefit of the successors in interest of the
respective parties, provided that (a) the assigning party remains liable under
the Confidentiality Agreement and the confidentiality and non-disclosure
obligations of Section 12 of this Agreement, and (b) the assignee or surviving
entity assumes in writing all of the assigning party's obligations under this
Agreement. Any assignment in violation of the foregoing shall be null and void.

17. REPRESENTATIONS, WARRANTIES AND COVENANTS.

       17.1 Each party hereby represents and warrants that it has the right,
power and authority to execute, deliver and perform its obligations under this
Agreement and the other agreements relating to the transaction contemplated
under this Agreement (the "Transaction Documents").

       17.2 Each party hereby represents that this Agreement and the other
Transaction Documents are a legal and valid obligation binding upon such party
and enforceable against such

                                       22
<PAGE>   24

party in accordance with their respective terms. The execution and delivery of
this Agreement and the other Transaction Documents does not, and the
consummation of the transaction contemplated hereby will not, violate, conflict
with or result in a breach of any provision of or constitute a default under, or
result in the termination of, or accelerate the performance required by, or
result in the creation of any lien, security interest, charge or encumbrance
upon, the patent rights and know-how licensed hereunder.

       17.3 Corixa hereby represents and warrants that:

              (i) Exhibit A sets forth a complete list of all patents and patent
applications that are owned or controlled by Corixa as of the Effective Date
that are necessary [*] exercise of the rights and licenses granted by Corixa to
Medicis hereunder;

              (ii) Corixa owns, or has the right, power and authority to license
to Medicis on the terms and conditions of this Agreement, the Corixa Patents and
Corixa Know-How free and clear of any liens, restrictions on use or encumbrances
of any nature whatsoever;

              (iii) Corixa has not admitted in writing that any claim of an
issued, unexpired patent included within the Corixa Patents is invalid or
unenforceable by the holder thereof by reissue, disclaimer or otherwise;

              (iv) Corixa has [*];

              (v) Corixa has not granted to any Third Party or Corixa Affiliate
any rights that conflict with [*] the rights granted by Corixa to Medicis under
this Agreement;

              (vi) To the best of Corixa's knowledge, the Corixa Patents are
valid and enforceable and the manufacture, sale or use of the Licensed Product
on the terms and conditions of this Agreement would not, if sold on the date
hereof, infringe any patent rights of any Third Party or Corixa Affiliate [*];

              (vii) As of the Effective Date, no patent or patent application
within the Corixa Patents is involved in or, to the best of Corixa's knowledge,
is threatened to be involved in, [*];

              (viii) Corixa has disclosed to Medicis all patent applications of
which Corixa is aware as of the Effective Date, that cover [*];

              (ix) To the best of Corixa's knowledge, no Corixa Patent infringes
or has been alleged to infringe any patent or other proprietary right of any
Third Party or Corixa Affiliate, [*];

              (x) Exhibit B sets forth all of the agreements entered into by
Corixa with a third party as of the Effective Date pursuant to which Corixa has
acquired intellectual property

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<PAGE>   25

included in the Corixa Patents or the Corixa Know-How ("Corixa Third Party
License Agreements") that are necessary [*];

              (xi) Exhibit C sets forth all of the agreements entered into by
Corixa with a Third Party or Corixa Affiliate as of the Effective Date pursuant
to which Corixa has licensed the Corixa Patents or the Corixa Know-How ("Corixa
Third Party Collaboration Agreements");

              (xii) Each of the agreements listed in Exhibit B [*];

              (xiii) [*].

       17.4 Corixa hereby covenants that:

              (i) Corixa will [*];

              (ii) Corixa will [*];

              (iii) Except in accordance with the terms of this Agreement,
Corixa will not [*];

              (iv) Corixa will [*];

              (v) Corixa will not grant during the term of this Agreement to any
third party any rights that conflict with the rights granted by Corixa to
Medicis under this Agreement;

              (vi) Corixa will [*]; and

              (vii) Corixa will take all actions which it considers reasonably
necessary to [*].

       17.5 Medicis hereby represents and warrants that it is not subject to any
obligations that would prevent it from entering into or performing its
obligations under this Agreement.

       17.6 Medicis hereby covenants that Medicis is aware of and will comply
with the Sections of the Corixa Third Party Licensor Agreements as agreed to in
good faith in writing by the parties prior to the Effective Date.

       17.7 LIMITATION OF LIABILITY. IN NO EVENT WILL EITHER PARTY BE LIABLE FOR
ANY SPECIAL, INCIDENTAL, CONSEQUENTIAL OR INDIRECT DAMAGES SUFFERED BY THE OTHER
PARTY ARISING IN ANY WAY OUT OF THIS AGREEMENT, HOWEVER CAUSED AND ON ANY THEORY
OF LIABILITY. THIS LIMITATION WILL APPLY EVEN IF THE AGGRIEVED PARTY HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

18. TERM AND TERMINATION.

       18.1 Unless otherwise terminated in accordance with the terms and
conditions set forth in this Section 18, this Agreement shall expire upon the
earlier of (i) the expiration, lapse or

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<PAGE>   26

invalidation of the last to expire of the Corixa Patents and the Joint Patents
in the Territory or (ii) the lapse or termination of Medicis' obligation to pay
royalties hereunder other than royalty payments payable by Medicis pursuant to
Section 19.4.

       18.2 This Agreement may not be terminated by either party except in
accordance with the following:

              (a) If either party is in material breach of any material
provision of this Agreement and if such breach is not cured within [*] (or in
the case of non-payment of money under Sections 5.1, 5.2, 5.3, 6.1 and 6.2 if
such payment obligation is not in dispute, [*] after receiving written notice
from the other party with respect to such breach, the non-breaching party shall
have the right to terminate this Agreement by giving [*] prior written notice to
the party in breach. The parties agree and acknowledge that any breach by
Medicis or Corixa of Section 8 and Sections 17.1 to 17.6 shall be deemed to be a
material breach of a material provision of this Agreement.

              (b) To the extent permitted by applicable law, either party may
terminate this Agreement if, at any time, the other party shall file in any
court or agency pursuant to any statute or regulation of the United States or of
any individual state or foreign country, a petition in bankruptcy or insolvency
or for reorganization or for an arrangement or for the appointment of a receiver
of trustee of the party or of its assets or for any other similar proceedings,
or if the other party proposes a written agreement of composition or extension
of its debts, or if the other party shall be served with an involuntary petition
against it, filed in any of such insolvency proceeding, and such petition shall
not be dismissed with sixty (60) days after the filing thereof, or if the other
party shall propose or be a party to any dissolution or liquidation, or if the
other party shall make an assignment for the benefit of creditors, or if the
other party's license, registration, approval or the like granted by any
official or governmental agency is rescinded, canceled or suspended.

       18.3 At any time after the expiration of the [*] anniversary of the
Effective Date, Medicis shall have the right to elect to terminate this
Agreement with [*] prior written notice to Corixa or by mutual agreement. [*]

19. RIGHTS AND OBLIGATIONS OF THE PARTIES UPON EXPIRATION OR TERMINATION.

       19.1 Following expiration of this Agreement in accordance with Section
18.1, subject to the terms and conditions of the Corixa Third Party Licensor
Agreements, Medicis shall have a nonexclusive, perpetual, fully-paid,
royalty-free right and license under the Corixa Patents, the Joint Patents and
the Corixa Know-How. [*].

       19.2 Subject to the terms of this Agreement, upon termination of this
Agreement Corixa shall have the right to retain any sums previously paid by
Medicis hereunder, and Medicis shall pay all sums accrued hereunder that are due
as of the date of termination. For the avoidance of doubt, as of the date of
termination Medicis shall not be liable for any sums that

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<PAGE>   27

would have been due and payable under this Agreement after the date of
termination, except as otherwise set forth in Section 19.3.

       19.3 Upon termination of this Agreement other than for Medicis' uncured
material breach, Medicis shall notify Corixa of the amount of Licensed Product
Medicis and its Affiliates, sublicensees and distributors then have on hand, the
sale of which would be subject to the payment of royalties pursuant to Section
6.1, and Medicis and its Affiliates, sublicensees and distributors thereupon
shall be permitted to sell such amount of Licensed Product, provided that
Medicis shall pay to Corixa such amounts payable thereon at such time as herein
provided.

       19.4 In the event that Medicis terminates this Agreement pursuant to
Section 18.2 as a result of Corixa's uncured material breach, then, subject to
Medicis having paid to Corixa all amounts payable to Corixa hereunder as of the
date of breach, (i) all rights and licenses granted to Corixa pursuant to this
Agreement with respect to the Licensed Product, including, without limitation,
rights and licenses granted to Corixa to all Medicis Patents, Joint Patents and
Medicis Know-How, shall revert to Medicis and Corixa shall retain no license
rights therein, provided that any sublicenses thereunder granted by Corixa to
any Third Party shall remain in effect as between Medicis and such Third Party;
(ii) during the period which is the lesser of either the period of [*], Medicis
shall have [*], and after such [*], Medicis shall have [*]; (iii) Corixa shall
use good faith efforts and cooperate with Medicis to transfer Corixa's product
registration rights to Medicis, (iv) subject to [*], Medicis shall have [*], and
(iv) each party shall retain its respective rights [*], except as provided for
by applicable law, provided that the parties agree to cooperate with each other
with respect to any patenting activities related to such [*]. In the event
either party wants to obtain a license to the other party's interest in [*]. In
addition, Corixa hereby agrees that in the event of any such termination, unless
[*] or [*], Corixa will [*].

       19.5 In the event that Corixa terminates this Agreement pursuant to
Section 18.2 as a result of Medicis' uncured material breach, then (i) all
rights and licenses granted to Medicis pursuant to this Agreement with respect
to the Licensed Product, including, without limitation, rights and licenses
granted to Medicis to all Corixa Patents, Joint Patents and Corixa Know-How,
shall revert to Corixa and Medicis shall retain no license rights therein;
provided that any sublicenses thereunder granted by Medicis to any Third Party
shall remain in effect as between Corixa and such Third Party, (ii) during the
[*], Corixa shall have [*], and after such [*] as provided herein, Corixa shall
have [*]; (iii) Medicis shall use good faith efforts and cooperate with Corixa
to transfer Medicis's product registration rights to Corixa, (iv) subject to
[*], Corixa shall have [*], and (v) each party shall retain its respective
rights in [*], except as provided for by applicable law, provided that the
parties agree to cooperate with each other with respect to any patenting
activities related to such [*]. In the event either party wants to obtain a
license to the other party's interest in such [*]. In addition, Medicis hereby
agrees that in the event of any such termination, unless [*] or [*], Medicis
will [*].

       19.6 Expiration or termination of this Agreement shall not relieve either
party of its obligations incurred prior to such expiration or termination. In
addition, Sections 1, 6.4, 7, 11.7, 11.8, 12, 13, 14.1, 19 and 20 shall survive
expiration or any termination of this Agreement.

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<PAGE>   28

       19.7 In the event that this Agreement is terminated pursuant to Section
18.3, then (i) all rights and licenses granted to Corixa and Medicis pursuant to
this Agreement with respect to the licensed patents shall revert to the
respective licensors and the respective licensees under this Agreement shall
retain no license rights therein, (ii) Joint Patents shall be jointly owned in
accordance with United States patent laws and each party's right, title and
interest therein shall be in accordance therewith; and (iii) Medicis and Corixa
agree to [*].

20. INDEMNIFICATION.

       20.1 Subject to Section 20.2 hereof, from and after the Effective Date,
except as otherwise herein specifically provided, each of the parties hereto
shall defend, indemnify and hold harmless the other party and its Affiliates,
successors and assigns, sublicensees and their respective officers, directors,
shareholders, partners and employees from and against all losses, damage,
liability and expense including legal fees but excluding punitive or
consequential damages (including lost profits) ("Damages") incurred thereby or
caused thereto arising out of or relating to (i) any breach or violation of, or
failure to properly perform, any covenant or agreement made by such Indemnifying
Party (as defined in Section 20.2) in this Agreement, unless waived in writing
by the Indemnified Party (as defined in Section 20.2); (ii) any breach of any of
the representations or warranties made by such Indemnifying Party in this
Agreement; or (iii) the gross negligence or willful misconduct of the
Indemnifying Party; provided, however, that this subSection (iii) shall not
apply to the extent such Damages are attributable to the gross negligence or
willful misconduct of the Indemnified Party. In addition to any other rights
Medicis may have at law or in equity, Corixa shall indemnify, defend and hold
harmless Medicis and its Affiliates, successors and assigns, sublicensees and
their respective officers, directors, shareholders, partners and employees from
and against all losses, damage, liability and expense including legal fees which
the indemnified party may incur, suffer or be required to pay resulting from or
arising out of: [*].

       20.2 If either Medicis or Corixa, or any Affiliate of Medicis or Corixa
(in each case an "Indemnified Party"), receives any written claim which it
believes is the subject of indemnity hereunder by either Corixa or Medicis, as
the case may be (in each case an "Indemnifying Party"), the Indemnified Party
shall, as soon as reasonably practicable after forming such belief, give notice
thereof to the Indemnifying Party, including full particulars of such claim to
the extent known to the Indemnified Party; provided, however, that the failure
to give timely notice to the Indemnifying Party as contemplated hereby shall not
release the Indemnifying Party from any liability to the Indemnified Party other
than any liabilities caused by such failure. The Indemnifying Party shall have
the right, by prompt notice to the Indemnified Party, to assume the defense of
such claim with counsel reasonably satisfactory to the Indemnified Party, and at
the cost of the Indemnifying Party. If the Indemnifying Party does not so assume
the defense of such claim, the Indemnified Party may assume such defense with
counsel of its choice at the sole expense of the Indemnifying Party. If the
Indemnifying Party so assumes such defense, the Indemnified Party may
participate therein through counsel of its choice, but the cost of such counsel
shall be borne solely by the Indemnified Party.

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<PAGE>   29

       20.3 The party not assuming the defense of any such claim shall render
all reasonable assistance to the party assuming such defense, and all
out-of-pocket costs of such assistance shall be borne solely by the Indemnifying
Party.

       20.4 No such claim shall be settled other than by the party defending the
same, and then only with the consent of the other party, which shall not be
unreasonably withheld; provided, however, that the Indemnified Party shall have
no obligation to consent to any settlement of any such claim which imposes on
the Indemnified Party any liability or obligation which cannot be assumed and
performed in full by the Indemnifying Party.

21. CLOSING.

       21.1 The consummation of the transactions contemplated herein (the
"Closing") shall take place within five (5) business days of satisfaction of the
conditions set forth in Section 21.2, or at such other date and time as mutually
agreed to by the parties (the "Effective Date").

       21.2 The effectiveness of this Agreement shall be subject to the
following conditions:

              (a) Corixa shall have received any consents or approvals required
under the Corixa Third Party License Agreements to enter into the transaction
contemplated hereby, in form and substance reasonably satisfactory to Medicis;

              (b) The parties hereto shall use reasonable best efforts to have
made any filing deemed to be required under the Hart-Scott-Rodino Antitrust
Improvement Act of 1976, as amended (the "HSR Act"), no later than August 25,
2000, the filing fee of which will be [*], and any waiting period under the HSR
Act to effect the transactions contemplated hereby shall have expired or been
earlier terminated; and

              (c) Neither Medicis nor Corixa shall have suffered a "Material
Adverse Event" prior to the Effective Date. For purposes hereto, a Material
Adverse Event shall mean an event which has had a material adverse effect on the
business, assets or financial condition of the other party or for Medicis, a
material adverse effect on the Licensed Products, the Corixa Patents or the
Corixa Know-How.

                            [Signature page follows]

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<PAGE>   30
        IN WITNESS WHEREOF, each of the parties hereto has caused this Agreement
to be executed by its duly authorized officer as of the date first written
above.

CORIXA CORPORATION                     MEDICIS PHARMACEUTICAL CORPORATION

By: /s/ Steven Gillis                      By: /s/ Mark A. Prygocki
    -------------------------------        -------------------------------------
    Name:  Steven Gillis, Ph.D.            Name:  Mark A. Prygocki, Sr.
    Title: Chairman and Chief Executive    Title: Chief Financial Officer
           Officer

          SIGNATURE PAGE TO THE MEDICIS DEVELOPMENT, COMMERCIALIZATION
                             AND LICENSE AGREEMENTExhibit 10.21

                              ALFACELL CORPORATION
                             PURCHASE AGREEMENT FOR
                             COMMON STOCK & WARRANTS

Alfacell Corporation
225 Belleville Avenue
Bloomfield, New Jersey 07003

Attention:  Kuslima Shogen, Chairman
            and Chief Executive Officer

Dear Ms. Shogen:

     The undersigned  acknowledges that there is no minimum proceeds requirement
for  the  closing  of  this  Offering,   the  Company  may  close  only  on  the
undersigned's  investment  and such  investment  may be  inadequate  to meet the
Company's cash requirements. The Company intends to utilize the proceeds of this
Offering for research and development and general corporate purposes.

     The undersigned  hereby subscribes to purchase  _________ units at $_______
per unit (the  "Units").  Each Unit  consists of two (2) shares of Common Stock,
$.001 par value per share (the  "Shares")  of Alfacell  Corporation,  a Delaware
corporation  (the  "Company")  one  (1)  three-year   warrant  (the  "Three-Year
Warrants") and one (1) five-year warrant (the "Five-Year Warrants").  The Three-
Year Warrants and the Five-Year  Warrants  (hereinafter  sometimes  collectively
referred to as the "Warrants") are exercisable  into one (1) Share (the "Warrant
Shares").  The Shares,  the Warrants and the Warrant  Shares are being sold in a
transaction  exempt  from  registration  under the  Securities  Act of 1933,  as
amended (the "Act"). The Three-Year  Warrants and the Five-Year Warrants will be
issued pursuant to a Warrant  Agreement in the form attached hereto as Exhibit A
and  Exhibit B,  respectively  executed  by the  Company  for the benefit of the
undersigned.  The Three-Year  Warrants will be exercisable at $_____ for a three
(3) year period  commencing  three months  after its issuance and the  Five-Year
Warrants  will be  exercisable  at $_____  per share for a five (5) year  period
commencing  three months after its issuance.  The undersigned  tenders  herewith
$___________ in full payment of the purchase price for the ____________ Units to
which the undersigned  subscribes (in the manner indicated on the signature page
hereof.)

     The undersigned  understands  that the right to transfer all or any part of
the  Shares,  the  Warrants  and  the  Warrant  Shares  (hereinafter   sometimes
collectively   referred  to  as  the  "Securities")  will  be  restricted.   The
undersigned may not transfer the Securities unless they are registered under the
Act and  applicable  state  securities or "blue sky" laws, or an exemption  from
such  registration  is available.  The  undersigned  recognizes that the Company
shall have no obligation to register the Securities, except as set forth herein.

The undersigned hereby represents, warrants and covenant that:

     1. The  undersigned  is acquiring the Shares and the Warrants,  and at such
time as the undersigned may exercise the Warrants,  the Warrant Shares,  for the
undersigned's   own  account  for   investment  and  not  with  a  view  towards
distribution. The undersigned will not sell, hypothecate,  transfer or otherwise
dispose of the Securities  unless such transaction has been registered under the
Act  or,  in  the  opinion  of  counsel  for  the  Company,  an  exemption  from
registration is available.

                                      - 1 -

<PAGE>

     2. (i) Please check here if the representation  contained in this paragraph
2(i) is applicable to the undersigned  _________.  (A)If an individual,  (a) the
undersigned's  individual  net worth or joint net worth  with the  undersigned's
spouse  exceeds  $1,000,000  as of the  date  hereof,  or (b) the  undersigned's
individual income has been in excess of $200,000 in each of 1998 and 1997 and is
expected  to be in excess of  $200,000 in 1999,  or (c)the  undersigned's  joint
income with the  undersigned's  spouse has been in excess of $300,000 in each of
1998 and 1997 and is expected  to be in excess of $300,000 in 1999;  or (B) if a
corporation,  partnership, or other entity, the foregoing representation applies
to all of the equity owners of the corporation, partnership, or entity.

          (ii) If a  corporation,  partnership,  or  other  entity,  was  such a
corporation,  partnership,  or other entity  formed for the specific  purpose of
acquiring the Shares? _____Yes _____ No

          (iii) If the answer to 2(ii) is yes,  how many equity  owners does the
corporation partnership or entity have? _____

     3.  Whether  or  not  the  representation  contained  in  paragraph  2(i)is
applicable to the  undersigned,  the undersigned has adequate means of providing
for the undersigned's  current needs and possible  contingencies and has no need
for  liquidity  of the  Securities.  The  undersigned's  overall  commitment  to
investments  is  not  disproportionate  to  the  undersigned's  net  worth,  and
acquisition of the Securities  will not cause such overall  commitment to become
excessive.  Prior to the execution hereof,  the undersigned has received and had
the  opportunity to review,  examine and read all  documents,  records and books
pertaining to this  investment,  including  the Company's  Annual Report on Form
10-K for the fiscal year ended July 31, 1999 (the "Disclosure Documents").

     4. The  undersigned  is  knowledgeable  and  experienced  in financial  and
business matters. The undersigned  recognizes and is fully cognizant of the fact
that the  investment  contemplated  hereby  involves a high degree of risk.  The
undersigned  is able to evaluate  the merits and risks of an  investment  in the
Securities.  The  undersigned has been given an opportunity to ask questions of,
and receive answers and obtain information from,  representatives of the Company
concerning the Company.

     5. The  undersigned  has been given no oral or written  representations  or
assurances  by the Company or any other person  acting or  purporting  to act on
behalf of the Company in connection with the  acquisition of the Securities,  in
each case except as provided herein or in the Disclosure Documents.

     6. The undersigned  understands and  specifically  acknowledges  and agrees
that  since  the  Securities  have  not  been  registered  under  the  Act,  the
certificates representing the Securities will bear a legend to such effect and a
stop transfer order will be placed on the  Securities in the Company's  transfer
books.

     7. By its acceptance hereof, the Company shall use its best efforts to file
a  registration  statement  (the  "Registration  Statement")  under  the  Act to
register the resale of the Shares and the Warrant  Shares.  The Company  further
agrees to use its best  efforts to cause such  Registration  Statement to become
effective.

     In  connection  with the  Registration  Statement,  the  undersigned  shall
provide the Company,  from time to time, as reasonably requested by the Company,
written information concerning its ownership of the Company's Securities,  their
intentions concerning the sale of its Shares and Warrant Shares and such other

                                      - 2 -

<PAGE>

matters as are  required  in order to enable the  Company to  prepare,  file and
obtain the effectiveness of such Registration Statement.  Notwithstanding any of
the foregoing,  the Company shall not be required to maintain the  effectiveness
of the  Registration  Statement  for more than two (2) years  after the  initial
effective date thereof.

     In connection with any such registration of Shares and Warrant Shares,  the
Company shall supply a reasonable number of prospectuses to the undersigned, use
its best  efforts to qualify the Shares and  Warrants  for sale in the states of
New York and New  Jersey  and  furnish  indemnification  in the manner set forth
below.

     The Company shall bear the entire cost and expense of any such registration
hereunder. Notwithstanding the foregoing, the undersigned shall bear the fees of
all persons  retained by it, such as counsel and  accountants,  and any transfer
taxes or  underwriting  discounts or  commissions  applicable  to the Shares and
Warrant Shares sold by it pursuant to the Registration Statement.

     The Company  shall  indemnify  and hold  harmless each holder of Shares and
Warrant Shares that are registered  pursuant to the  Registration  Statement and
each  underwriter,  within the meaning of the Act, who may purchase from or sell
for any such holder any such Shares or Warrant  Shares and each person,  if any,
who controls any such holder or underwriter  within the meaning of the Act, from
and against any and all losses,  claims,  damages and liabilities  caused by any
untrue statement of a material fact contained in the  Registration  Statement or
any post-effective amendment thereto or any prospectus included therein required
to be filed or  furnished in  connection  therewith or caused by any omission to
state therein a material fact required to be stated therein in order to make the
statements  made therein,  in light of the  circumstances  under which they were
made,  not  misleading,  except  insofar  as such  losses,  claims,  damages  or
liabilities  are caused by any such  untrue  statement  or  omission  based upon
information  furnished  or required to be furnished in writing to the Company by
such holder or underwriter  expressly for use therein;  provided,  however, that
such holder or underwriter  shall  indemnify the Company,  its  directors,  each
officer signing the Registration Statement and each person, if any, who controls
the Company  within the meaning of the Act, from and against any and all losses,
claims,  damages and  liabilities  caused by any untrue  statement of a material
fact contained in any  Registration  Statement or any  post-effective  amendment
thereto or any  prospectus  included  therein  required to be filed or furnished
pursuant  thereto or caused by any  omission  to state  therein a material  fact
required to be stated therein in order to make the statements  made therein,  in
light of the circumstances  under which they were made, not misleading,  insofar
as such  losses,  claims,  damages  or  liabilities  are  caused  by any  untrue
statement or omission based upon information furnished in writing to the Company
by any such holder or underwriter expressly for use therein.

     If the  indemnification  provided  for herein from either the holder of the
Shares and Warrant Shares or the Company is unavailable to an indemnified  party
(the  "Indemnitee")  hereunder  in respect  of any  losses,  claims,  damages or
liabilities (or actions in respect thereof)  referred to herein,  then the party
responsible for such indemnification (the "Indemnitor"), in lieu of indemnifying
the Indemnitee, shall contribute to the amount paid or payable by the Indemnitee
as a result of such losses, claims, damages or liabilities in such proportion as
is appropriate to reflect the relative fault of the Indemnitor and Indemnitee in
connection  with the actions which resulted in such losses,  claims,  damages or
liabilities  (including legal or other fees and expenses  reasonably incurred in
connection with any  investigation or proceeding) as well as any other equitable
considerations.

                                      - 3 -

<PAGE>

     If  indemnification  is available,  the  Indemnitor  shall  indemnify  each
Indemnitee to the full extent provided for herein without regard to the relative
fault of the  Indemnitor,  the Indemnitee or any other  equitable  consideration
provided for hereunder.

     After the Registration  Statement  becomes effective and in connection with
the sale of the Shares and Warrant Shares under such Registration Statement, the
undersigned  shall take such steps as may be  necessary to ensure that the offer
and  sale  thereof  are in  compliance  with  the  requirements  of the  federal
securities  laws,  including,  but not  limited  to,  compliance  with the anti-
manipulation requirements of the Securities Exchange Act of 1934, as amended.

     By  its  acceptance  hereof,  the  Company  hereby  acknowledges  that  the
foregoing  accurately  reflects its  understanding  concerning  the  transaction
contemplated hereby.

                                             Very truly yours,

                                            -----------------------------------
                                                         (Signature)

                                            -----------------------------------
                                                  Please type or print name
                                                  (and title if applicable)

                                            Name & Address (as it should appear
                                            on certificates):

                                            ------------------------------------

                                            ------------------------------------

                                            ------------------------------------

                                            ------------------------------------
                                                   Social Security Number or
                                               Taxpayer Identification Number

                                            (H)___________________(W)___________
                                                     Telephone Number

                                            ------------------------------------
                                                        As of Date

                                            ------------------------------------
                                                       Number of Units

                                            ------------------------------------
                                                    Amount of Subscription
                                                       (U.S. Dollars)

ACCEPTED AND AGREED:                        Deliver to Address: (if
ALFACELL CORPORATION                        different from above)

                                            -----------------------------------

----------------------------                -----------------------------------
 Name:
 Title:

                                      - 4 -

<PAGE>

                                    Exhibit A

     WARRANT TO PURCHASE  _____________  SHARES OF COMMON  STOCK VOID AFTER 5:00
p.m. NEW JERSEY TIME, ON _______________.  THIS WARRANT AND THE SHARES OF COMMON
STOCK  ISSUABLE  UPON THE  EXERCISE  HEREOF  HAVE  BEEN AND  WILL BE  ISSUED  IN
TRANSACTIONS WHICH HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED  (THE  "ACT"),  OR UNDER ANY  STATE  SECURITIES  OR BLUE SKY LAWS.  THIS
WARRANT AND SUCH SHARES MAY NOT BE SOLD, TRANSFERRED,  PLEDGED,  HYPOTHECATED OR
OTHERWISE  DISPOSED  OF, IN WHOLE OR IN PART,  IN THE  ABSENCE  OF AN  EFFECTIVE
REGISTRATION  STATEMENT UNDER THE ACT AND APPLICABLE STATE LAW, OR AN OPINION OF
COUNSEL ACCEPTABLE TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.

NO.                                                                      SHARES
---                                                                      ------

                              ALFACELL CORPORATION

     This certifies  that, for value  received,  _________________________,  the
registered  holder  hereof or  assigns  (the  "Warrantholder")  is  entitled  to
purchase from Alfacell Corporation,  a Delaware corporation (the "Company"),  at
any time on and after  _____________,  and before 5:00 p.m., New Jersey time, on
_____________  (the  "Termination  Date"),  at the purchase  price of $_____ per
share (the "Exercise  Price"),  the number of shares of Common Stock,  par value
$.001 per share,  of the  Company  set forth above (the  "Warrant  Stock").  The
number of shares of Warrant Stock,  the Termination  Date and the Exercise Price
per share of this Warrant  shall be subject to  adjustment  from time to time as
set forth below.

SECTION I.      TRANSFER OR EXCHANGE OF WARRANT.

     The Company  shall be entitled to treat the  Warrantholder  as the owner in
fact hereof for all purposes and shall not be bound to recognize  any  equitable
or other claim to or interest in this  Warrant on the part of any other  person.
This Warrant shall be transferable only on the books of the Company,  maintained
at its principal office upon delivery of this Warrant  Certificate duly endorsed
by the Warrantholder or by his duly authorized  attorney or  representative,  or
accompanied  by proper  evidence  of  succession,  assignment  or  authority  to
transfer.  Upon any  registration  of transfer,  the Company shall deliver a new
Warrant Certificate or Certificates to the persons entitled thereto.

SECTION II.     TERM OF WARRANT; EXERCISE OF WARRANTS.

     A.  Termination.  The  Company  may,  in its sole  discretion,  extend  the
Termination Date with respect to the exercise of this Warrant upon notice to the
Warrantholder. As used herein, "Termination Date" shall be deemed to include any
such extensions.

     B.  Exercise.  This Warrant shall be exercised by surrender to the Company,
at its principal office, of this Warrant Certificate, together with the Purchase
Form attached hereto duly completed and signed,  and upon payment to the Company
of the Exercise Price for the number of shares of Warrant Stock in

                                      - 5 -

<PAGE>

respect  of which  this  Warrant is then  exercised.  Payment  of the  aggregate
Exercise Price shall be made in cash or by certified or official bank check.

     C. Warrant Certificate.  Subject to Section III hereof, upon such surrender
of this Warrant Certificate and payment of the Exercise Price as aforesaid,  the
Company  shall issue and cause to be delivered  to or upon the written  order of
the Warrantholder a certificate or certificates for the number of full shares of
Warrant  Stock so purchased  upon the exercise of such  Warrant,  together  with
cash, as provided in Section VI hereof,  in respect of any fractional  shares of
Warrant  Stock  otherwise  issuable upon such  surrender.  Such  certificate  or
certificates  representing the Warrant Stock shall be deemed to have been issued
and any person so  designated to be named therein shall be deemed to have become
a holder of record of such shares of Warrant  Stock as of the date of receipt by
the Company of this Warrant  Certificate  and payment of the  Exercise  Price as
aforesaid;  provided, however, that if, at the date of surrender of this Warrant
Certificate  and  payment of the  Exercise  Price,  the  transfer  books for the
Warrant  Stock or other  class of stock  purchasable  upon the  exercise of this
Warrant  shall be closed,  the  certificate  or  certificates  for the shares of
Warrant Stock in respect of which this Warrant is then exercised shall be deemed
issuable as of the date on which such books shall next be opened (whether before
or after the Termination Date) and until such date the Company shall be under no
duty to deliver  any  certificate  for such  shares of Warrant  Stock;  provided
further,  however,  that the transfer books of record, unless otherwise required
by law, shall not be closed at any one time for a period longer than twenty (20)
days. The rights of purchase  represented by this Warrant shall be  exercisable,
at the  election  of the  Warrantholder,  either in full or from time to time in
part,  and, in the event that this Warrant is exercised in respect of fewer than
all of the shares of Warrant  Stock  purchasable  on such  exercise  at any time
prior  to  the  Termination  Date,  a new  Warrant  Certificate  evidencing  the
remaining Warrant or Warrants will be issued,  and the Company shall deliver the
new Warrant  Certificate  or  Certificates  pursuant to the  provisions  of this
Section.

SECTION III.    PAYMENT OF TAXES.

     The Company will pay all documentary  stamp taxes, if any,  attributable to
the initial  issuance of the shares of Warrant  Stock upon the  exercise of this
Warrant;  provided,  however,  that the Warrantholder shall pay any tax or taxes
which  may be  payable  in  respect  of any  transfer  involved  in the issue or
delivery of Warrant  Certificates or the  certificates for the shares of Warrant
Stock in a name  other than that of the  Warrantholder  in respect of which this
Warrant or shares of Warrant Stock are issued.

SECTION IV.     MUTILATED OR MISSING WARRANT CERTIFICATES.

     In case  this  Warrant  Certificate  shall be  mutilated,  lost,  stolen or
destroyed,  the Company shall,  at the request of the  Warrantholder,  issue and
deliver,  in  exchange  and  substitution  for  and  upon  cancellation  of this
certificate if mutilated, or in lieu of and in substitution for this certificate
if lost,  stolen or  destroyed,  a new  Warrant  Certificate  of like  tenor and
representing an equivalent right or interest,  but only upon receipt of evidence
satisfactory  to the Company of such loss,  theft or destruction of this Warrant
Certificate and indemnity, if requested, also satisfactory to the Company.

                                      - 6 -

<PAGE>

SECTION V.      RESERVATION OF SHARES OF WARRANT STOCK.

     There has been  reserved,  and the Company shall at all times keep reserved
so long as this Warrant remains outstanding,  out of its authorized Common Stock
a number of shares of Common Stock sufficient to provide for the exercise of the
rights of purchase  represented  by this  Warrant.  The  transfer  agent for the
Common Stock and every subsequent transfer agent for any shares of the Company's
capital  stock  issuable  upon the exercise of this Warrant will be  irrevocably
authorized and directed at all times to reserve such number of authorized shares
as shall be requisite for such purpose.

SECTION VI.     FRACTIONAL SHARES.

     No  fractional  shares or scrip  representing  fractional  shares  shall be
issued upon the  exercise of this  Warrant.  With  respect to any  fraction of a
share called for upon the exercise of this Warrant, the Company shall pay to the
Warrantholder an amount in cash equal to such fraction multiplied by the current
market price of such fractional share. "Market Price", as of any date means, (i)
the last  reported  sale price for the shares of Common Stock as reported by the
National  Association of Securities Dealers Automated  Quotation National Market
System,  ("NASDAQ-NMS"),  (ii) the  closing  bid price for the  shares of Common
Stock as reported by the National  Association of Securities  Dealers  Automated
Quotation  System  ("NASDAQ") if the shares are not traded on NASDAQ-NMS,  (iii)
the average of the closing bid and closing  asked  prices of the Common Stock as
reported  by the  National  Quotations  Bureau if the  shares  are not traded on
NASDAQ;  (iv) the last  reported  sale price,  if the shares of Common Stock are
listed  on a  national  securities  exchange  or (v) if market  value  cannot be
calculated as of such date on any of the foregoing  basis, the fair market price
determined  by the Board of  Directors of the  Company,  acting with  reasonable
business judgment.

SECTION VII.    EXERCISE PRICE; ANTI-DILUTION PROVISIONS.

     A. Exercise  Price.  The shares of Warrant Stock shall be purchasable  upon
the exercise of this Warrant,  at a price of $_____ per share.  The Company may,
in its sole discretion,  reduce the Exercise Price applicable to the exercise of
this Warrant upon notice to the Warrantholder.  As used herein, "Exercise Price"
shall be deemed to include any such reduction.

      If the Company shall at any time issue Common Stock by way of dividend or
other distribution on any stock of the Company or effect a stock split or
reverse stock split of the outstanding shares of Common Stock, the Exercise
Price shall be proportionately decreased in the case of such issuance (on the
day following the date fixed for determining stockholders entitled to receive
such dividend or other distribution or such stock split) or increased in the
case of such reverse stock split (on the date that such reverse stock split
shall become effective), by multiplying the Exercise Price in effect immediately
prior to the stock dividend or other distribution, stock split or reverse stock
split by a fraction, the numerator of which is the number of shares of Common
Stock outstanding immediately prior to such stock dividend or other
distribution, stock split or reverse stock split, and the denominator of which
is the number of shares of Common Stock outstanding immediately after such stock
dividend or other distribution, stock split or reverse stock split.

                                      - 7 -

<PAGE>

     B. No  Impairment.  The Company (a) will not  increase the par value of any
shares of stock  receivable  upon the exercise of this Warrant  above the amount
payable therefor upon such exercise, and (b) will take all such action as may be
necessary or appropriate in order that the Company may validly and legally issue
fully paid and  nonassessable  shares of Common  Stock upon the exercise of this
Warrant.

     C. Number of Shares  Adjusted.  Upon any  adjustment of the Exercise  Price
pursuant to this Warrant, the Warrantholder shall thereafter (until another such
adjustment)  be entitled to purchase upon the exercise of this  Warrant,  at the
new Exercise Price, the number of shares,  calculated to the nearest full share,
obtained by multiplying the number of shares of Warrant Stock initially issuable
upon exercise of this Warrant by the Exercise Price in effect on the date hereof
and dividing the product so obtained by the new Exercise Price.

SECTION VIII.   RECLASSIFICATION, REORGANIZATION OR MERGER.

     In case of any reclassification,  capital reorganization or other change of
outstanding  shares of Common  Stock of the Company  (other than a change in par
value or as a result of an issuance of Common  Stock by way of dividend or other
distribution  or of a stock  split or  reverse  stock  split)  or in case of any
consolidation or merger of the Company with or into another  corporation  (other
than a merger with a subsidiary  in which  merger the Company is the  continuing
corporation  and  which  does  not  result  in  any  reclassification,   capital
reorganization  or other  change of  outstanding  shares of Common  Stock of the
Company  issuable  upon  exercise  of this  Warrant)  or in case of any  sale or
conveyance to another  corporation of the property of the Company as an entirety
or substantially as an entirety,  the Company shall cause effective provision to
be made so that the Warrantholder shall have the right thereafter, by exercising
this  Warrant,  to  purchase  the kind and  amount  of shares of stock and other
securities and property the Warrantholder would have been entitled to receive if
the  Warrantholder  had  exercised  this  Warrant   immediately  prior  to  such
reclassification, capital reorganization or other change, consolidation, merger,
sale or conveyance.  Any such provision shall include  provision for adjustments
which shall be as nearly  equivalent as may be  practicable  to the  adjustments
provided for in this  Warrant.  The  foregoing  provisions of this Section shall
similarly apply to successive  reclassifications,  capital  reorganizations  and
changes of shares of Common  Stock and to  successive  consolidations,  mergers,
sales and conveyances.

SECTION IX.     REGISTRATION RIGHTS.

     The  Warrantholder  shall have the registration  rights with respect to the
resale of the Warrant Stock as set forth in Section 7 of the Purchase  Agreement
by and between the Company and the Warrantholder of even date herewith.

SECTION X.      NOTICES TO WARRANTHOLDERS.

     So long as this Warrant shall be  outstanding  and  unexercised  (a) if the
Company shall pay any dividend or make any distribution upon the Common Stock or
(b) if the Company  shall offer to the holders of Common Stock for  subscription
or purchase by them any shares of stock of any class or any other rights or (c)

                                      - 8 -

<PAGE>

if any capital  reorganization of the Company,  reclassification  of the capital
stock of the  Company,  consolidation  or  merger  of the  Company  with or into
another corporation,  sale, lease or transfer of all or substantially all of the
assets of the Company to another  corporation,  or the voluntary or  involuntary
dissolution,  liquidation or winding up of the Company shall be effected,  then,
in any such case, the Company shall cause to be delivered to the  Warrantholder,
at least ten days prior to the date specified in (i) or (ii) below,  as the case
may be, a notice  containing  a brief  description  of the  proposed  action and
stating  the date on which (i) a record is to be taken for the  purpose  of such
dividend  or  distribution,  or  (ii)  such  reclassification,   reorganization,
consolidation, merger, conveyance, lease, dissolution, liquidation or winding up
is to take place and the date,  if any, as of which the holders of Common  Stock
of record  shall be  entitled  to  exchange  their  shares  of Common  Stock for
securities   or  other   property   deliverable   upon  such   reclassification,
reorganization,  consolidation,  merger, conveyance, dissolution, liquidation or
winding up.

SECTION XI.     NOTICES.

     Any notice pursuant to this Warrant by the Company or by the  Warrantholder
shall be in writing and shall be deemed to have been duly given if  delivered or
mailed certified mail, return receipt requested, (a) if to the Company, to it at
225 Belleville Avenue,  Bloomfield, New Jersey 07003, Attention: Chief Executive
Officer and (b) if to the  Warrantholder to the Warrantholder at the address set
forth on the  signature  page  hereto.  Each party  hereto may from time to time
change the address to which such  party's  notices are to be delivered or mailed
hereunder by notice in accordance herewith to the other party.

SECTION XII.    SUCCESSORS.

     All the covenants  and  provisions of this Warrant by or for the benefit of
the  Company or the  Warrantholder  shall bind and inure to the benefit of their
respective successors and assigns hereunder.

SECTION XIII.   APPLICABLE LAW.

     This  Warrant  shall be deemed to be a contract  made under the laws of the
State of Delaware  applicable to agreements made and to be performed entirely in
Delaware and for all purposes shall be construed in accordance with the internal
laws of Delaware  without  giving  effect to the  conflicts  of laws  principles
thereof.

SECTION XIV.    BENEFITS OF THIS WARRANT.

     Nothing  in this  Warrant  shall  be  construed  to give to any  person  or
corporation  other than the Company and the Warrantholder any legal or equitable
right, remedy or claim under this Warrant and this Warrant shall be for the sole
and exclusive benefit of the Company and the Warrantholder.

                                     - 9 -

<PAGE>

     IN  WITNESS  WHEREOF,   the  parties  hereto  have  executed  this  Warrant
Certificate or caused this Warrant Certificate to be duly executed as of the day
and year first above written.

ALFACELL CORPORATION

By: ---------------------
Name:
Title:

WARRANTHOLDER

-------------------------
Name:

Address:

-------------------------
Social Security or
Taxpayer Indentification Number

                                     - 10 -

<PAGE>

                                    EXHIBIT B

     WARRANT TO PURCHASE ___________ SHARES OF COMMON STOCK VOID AFTER 5:00 p.m.
NEW JERSEY TIME, ON ______________.  THIS WARRANT AND THE SHARES OF COMMON STOCK
ISSUABLE UPON THE EXERCISE  HEREOF HAVE BEEN AND WILL BE ISSUED IN  TRANSACTIONS
WHICH HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
"ACT"),  OR UNDER ANY STATE  SECURITIES OR BLUE SKY LAWS.  THIS WARRANT AND SUCH
SHARES MAY NOT BE SOLD, TRANSFERRED, PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED
OF, IN WHOLE OR IN PART, IN THE ABSENCE OF AN EFFECTIVE  REGISTRATION  STATEMENT
UNDER THE ACT AND APPLICABLE  STATE LAW, OR AN OPINION OF COUNSEL  ACCEPTABLE TO
THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.

NO. ____                                                        _________ SHARES

                              ALFACELL CORPORATION

     This certifies  that,  for value  received,  ______________  the registered
holder  hereof or assigns  (the  "Warrantholder")  is entitled to purchase  from
Alfacell Corporation, a Delaware corporation (the "Company"), at any time on and
after ____________,  and before 5:00 p.m., New Jersey time, on ____________ (the
"Termination  Date"),  at the purchase  price of $____ per share (the  "Exercise
Price"), the number of shares of Common Stock, par value $.001 per share, of the
Company set forth above (the "Warrant  Stock").  The number of shares of Warrant
Stock,  the  Termination  Date and the Exercise  Price per share of this Warrant
shall be subject to adjustment from time to time as set forth below.

SECTION I.      TRANSFER OR EXCHANGE OF WARRANT.

     The Company  shall be entitled to treat the  Warrantholder  as the owner in
fact hereof for all purposes and shall not be bound to recognize  any  equitable
or other claim to or interest in this  Warrant on the part of any other  person.
This Warrant shall be transferable only on the books of the Company,  maintained
at its principal office upon delivery of this Warrant  Certificate duly endorsed
by the Warrantholder or by his duly authorized  attorney or  representative,  or
accompanied  by proper  evidence  of  succession,  assignment  or  authority  to
transfer.  Upon any  registration  of transfer,  the Company shall deliver a new
Warrant Certificate or Certificates to the persons entitled thereto.

SECTION II.     TERM OF WARRANT; EXERCISE OF WARRANTS

     A.  Termination.  The  Company  may,  in its sole  discretion,  extend  the
Termination Date with respect to the exercise of this Warrant upon notice to the
Warrantholder. As used herein, "Termination Date" shall be deemed to include any
such extensions.

     B.  Exercise.  This Warrant shall be exercised by surrender to the Company,
at its principal office, of this Warrant Certificate, together with the Purchase
Form attached hereto duly completed and signed,  and upon payment to the Company
of the Exercise Price for the number of shares of Warrant Stock in

                                     - 11 -

<PAGE>

respect  of which  this  Warrant is then  exercised.  Payment  of the  aggregate
Exercise Price shall be made in cash or by certified or official bank check.

     C. Warrant Certificate.  Subject to Section III hereof, upon such surrender
of this Warrant Certificate and payment of the Exercise Price as aforesaid,  the
Company  shall issue and cause to be delivered  to or upon the written  order of
the Warrantholder a certificate or certificates for the number of full shares of
Warrant  Stock so purchased  upon the exercise of such  Warrant,  together  with
cash, as provided in Section VI hereof,  in respect of any fractional  shares of
Warrant  Stock  otherwise  issuable upon such  surrender.  Such  certificate  or
certificates  representing the Warrant Stock shall be deemed to have been issued
and any person so  designated to be named therein shall be deemed to have become
a holder of record of such shares of Warrant  Stock as of the date of receipt by
the Company of this Warrant  Certificate  and payment of the  Exercise  Price as
aforesaid;  provided, however, that if, at the date of surrender of this Warrant
Certificate  and  payment of the  Exercise  Price,  the  transfer  books for the
Warrant  Stock or other  class of stock  purchasable  upon the  exercise of this
Warrant  shall be closed,  the  certificate  or  certificates  for the shares of
Warrant Stock in respect of which this Warrant is then exercised shall be deemed
issuable as of the date on which such books shall next be opened (whether before
or after the Termination Date) and until such date the Company shall be under no
duty to deliver  any  certificate  for such  shares of Warrant  Stock;  provided
further,  however,  that the transfer books of record, unless otherwise required
by law, shall not be closed at any one time for a period longer than twenty (20)
days. The rights of purchase  represented by this Warrant shall be  exercisable,
at the  election  of the  Warrantholder,  either in full or from time to time in
part,  and, in the event that this Warrant is exercised in respect of fewer than
all of the shares of Warrant  Stock  purchasable  on such  exercise  at any time
prior  to  the  Termination  Date,  a new  Warrant  Certificate  evidencing  the
remaining Warrant or Warrants will be issued,  and the Company shall deliver the
new Warrant  Certificate  or  Certificates  pursuant to the  provisions  of this
Section.

SECTION III.    PAYMENT OF TAXES.

     The Company will pay all documentary  stamp taxes, if any,  attributable to
the initial  issuance of the shares of Warrant  Stock upon the  exercise of this
Warrant;  provided,  however,  that the Warrantholder shall pay any tax or taxes
which  may be  payable  in  respect  of any  transfer  involved  in the issue or
delivery of Warrant  Certificates or the  certificates for the shares of Warrant
Stock in a name  other than that of the  Warrantholder  in respect of which this
Warrant or shares of Warrant Stock are issued.

SECTION IV.     MUTILATED OR MISSING WARRANT CERTIFICATES.

     In case  this  Warrant  Certificate  shall be  mutilated,  lost,  stolen or
destroyed,  the Company shall,  at the request of the  Warrantholder,  issue and
deliver,  in  exchange  and  substitution  for  and  upon  cancellation  of this
certificate if mutilated, or in lieu of and in substitution for this certificate
if lost,  stolen or  destroyed,  a new  Warrant  Certificate  of like  tenor and
representing an equivalent right or interest,  but only upon receipt of evidence
satisfactory  to the Company of such loss,  theft or destruction of this Warrant
Certificate and indemnity, if requested, also satisfactory to the Company.

                                     - 12 -

<PAGE>

SECTION V.      RESERVATION OF SHARES OF WARRANT STOCK.

     There has been  reserved,  and the Company shall at all times keep reserved
so long as this Warrant remains outstanding,  out of its authorized Common Stock
a number of shares of Common Stock sufficient to provide for the exercise of the
rights of purchase  represented  by this  Warrant.  The  transfer  agent for the
Common Stock and every subsequent transfer agent for any shares of the Company's
capital  stock  issuable  upon the exercise of this Warrant will be  irrevocably
authorized and directed at all times to reserve such number of authorized shares
as shall be requisite for such purpose.

SECTION VI.     FRACTIONAL SHARES.

     No  fractional  shares or scrip  representing  fractional  shares  shall be
issued upon the  exercise of this  Warrant.  With  respect to any  fraction of a
share called for upon the exercise of this Warrant, the Company shall pay to the
Warrantholder an amount in cash equal to such fraction multiplied by the current
market price of such fractional share. "Market Price", as of any date means, (i)
the last  reported  sale price for the  shares of Common  Stock as  reported  by
National  Association of Securities Dealers Automated  Quotation National Market
System,  ("NASDAQ-NMS"),  (ii) the  closing  bid price for the  shares of Common
Stock as reported by the National  Association of Securities  Dealers  Automated
Quotation  System  ("NASDAQ") if the shares are not traded as NASDAQ-NMS,  (iii)
the average of the closing bid and closing  asked  prices of the Common Stock as
reported  by the  National  Quotations  Bureau if the  shares  are not traded on
NASDAQ;  (iv) the last  reported  sale price,  if the shares of Common Stock are
listed  on a  national  securities  exchange  or (v) if market  value  cannot be
calculated as of such date on any of the foregoing  basis, the fair market price
determined  by the Board of  Directors of the  Company,  acting with  reasonable
business judgment.

SECTION VII.    EXERCISE PRICE; ANTI-DILUTION PROVISIONS.

     A. Exercise  Price.  The shares of Warrant Stock shall be purchasable  upon
the exercise of this Warrant, at a price of $____ per share. The Company may, in
its sole  discretion,  reduce the Exercise  Price  applicable to the exercise of
this Warrant upon notice to the Warrantholder.  As used herein, "Exercise Price"
shall be deemed to include any such reduction.

     If the Company  shall at any time issue  Common Stock by way of dividend or
other  distribution  on any  stock of the  Company  or  effect a stock  split or
reverse  stock split of the  outstanding  shares of Common  Stock,  the Exercise
Price shall be  proportionately  decreased in the case of such  issuance (on the
day following the date fixed for  determining  stockholders  entitled to receive
such  dividend or other  distribution)  or such stock split or  increased in the
case of such  reverse  stock  split (on the date that such  reverse  stock split
shall become effective), by multiplying the Exercise Price in effect immediately
prior to the stock  dividend,  stock split or reverse stock split by a fraction,
the  numerator  of which is the  number of shares  of Common  Stock  outstanding
immediately  prior to such stock  dividend,  stock split or reverse stock split,
and the denominator of which is the number of shares of Common Stock outstanding
immediately after such stock dividend, stock split or reverse stock split.

                                     - 13 -

<PAGE>

     B. No  Impairment.  The Company (a) will not  increase the par value of any
shares of stock  receivable  upon the exercise of this Warrant  above the amount
payable therefor upon such exercise, and (b) will take all such action as may be
necessary or appropriate in order that the Company may validly and legally issue
fully paid and  nonassessable  shares of Common  Stock upon the exercise of this
Warrant.

     C. Number of Shares  Adjusted.  Upon any  adjustment of the Exercise  Price
pursuant to this Warrant, the Warrantholder shall thereafter (until another such
adjustment)  be entitled to purchase upon the exercise of this  Warrant,  at the
new Exercise Price, the number of shares,  calculated to the nearest full share,
obtained by multiplying the number of shares of Warrant Stock initially issuable
upon exercise of this Warrant by the Exercise Price in effect on the date hereof
and dividing the product so obtained by the new Exercise Price.

SECTION VIII.   RECLASSIFICATION, REORGANIZATION OR MERGER.

     In case of any reclassification,  capital reorganization or other change of
outstanding  shares of Common  Stock of the Company  (other than a change in par
value or as a result of an issuance of Common  Stock by way of dividend or other
distribution  or of a stock  split or  reverse  stock  split)  or in case of any
consolidation or merger of the Company with or into another  corporation  (other
than a merger with a subsidiary  in which  merger the Company is the  continuing
corporation  and  which  does  not  result  in  any  reclassification,   capital
reorganization  or other  change of  outstanding  shares of Common  Stock of the
Company  issuable  upon  exercise  of this  Warrant)  or in case of any  sale or
conveyance to another  corporation of the property of the Company as an entirety
or substantially as an entirety,  the Company shall cause effective provision to
be made so that the Warrantholder shall have the right thereafter, by exercising
this  Warrant,  to  purchase  the kind and  amount  of shares of stock and other
securities and property the Warrantholder would have been entitled to receive if
the  Warrantholder  had  exercised  this  Warrant   immediately  prior  to  such
reclassification, capital reorganization or other change, consolidation, merger,
sale or conveyance.  Any such provision shall include  provision for adjustments
which shall be as nearly  equivalent as may be  practicable  to the  adjustments
provided for in this  Warrant.  The  foregoing  provisions of this Section shall
similarly apply to successive  reclassifications,  capital  reorganizations  and
changes of shares of Common  Stock and to  successive  consolidations,  mergers,
sales and conveyances.

SECTION IX.     REGISTRATION RIGHTS

     A.  Registration  Rights.  As  soon as  practicable  after  the  successful
completion of the offering (the  "Offering")  of the Company's  Common Stock and
this  Warrant  pursuant to its Private  Placement  the Company will use its best
efforts  to file,  obtain  and  maintain  the  effectiveness  of a  registration
statement  (the  "Registration  Statement")  under the Act with  respect  to the
Common Stock and the Warrant Stock.

     In connection with the  Registration  Statement,  the  Warrantholder  shall
provide the Company,  from time to time, as reasonably requested by the Company,
written information  concerning the  Warrantholder's  ownership of the Company's
securities, any intentions concerning the sale of Warrants, Common Stock and

                                     - 14 -

<PAGE>

Warrant  Stock and such  other  matters as are  required  in order to enable the
Company  to  prepare,  file and obtain the  effectiveness  of such  Registration
Statement.  Notwithstanding  any of the  foregoing,  the  Company  shall  not be
required to maintain the  effectiveness of the  Registration  Statement for more
than three (3) years after the initial effective date thereof.

     B. Blue Sky. In  connection  with any such  registration  of the  Warrants,
Common Stock and Warrant Stock, the Company shall supply  prospectuses,  use its
best efforts to qualify the Warrants, Common Stock and Warrant Stock for sale in
the states of New York and New Jersey and furnish  indemnification in the manner
set forth below.

     C. Expenses. The Company shall bear the entire cost and expense of any such
registration hereunder.  Notwithstanding the foregoing,  the Warrantholder shall
pay the fees of all  persons  retained  by  Warrantholder,  such as counsel  and
accountants,  and any transfer  taxes or  underwriting  discounts or commissions
applicable  to  the  Warrants,  Common  Stock  and  Warrant  Stock  sold  by the
Warrantholder pursuant to the Registration Statement.

     D.  Indemnification.  The Company  shall  indemnify  and hold  harmless the
Warrantholder  for Warrants,  Common Stock and Warrant Stock that are registered
pursuant to the Registration Statement and each underwriter,  within the meaning
of the  Act,  who may  purchase  from or sell  for the  Warrantholder  any  such
Warrants,  Common Stock and Warrant Stock, and each person, if any, who controls
the Warrantholder or underwriter within the meaning of the Act, from and against
any and all  losses,  claims,  damages  and  liabilities  caused  by any  untrue
statement  of a material  fact  contained in the  Registration  Statement or any
post- effective amendment thereto or any prospectus included therein required to
be filed or furnished in connection therewith or caused by any omission to state
therein a  material  fact  required  to be stated  therein  in order to make the
statements  made therein,  in light of the  circumstances  under which they were
made,  not  misleading,  except  insofar  as such  losses,  claims,  damages  or
liabilities  are caused by any such  untrue  statement  or  omission  based upon
information  furnished  or required to be furnished in writing to the Company by
the Warrantholder or underwriter expressly for use therein.

     The Warrantholder agrees to indemnify and hold harmless the Company and its
directors,  officers,  employees and agents against any and all losses,  claims,
damages  or  liabilities,  joint or  several,  to which  they or any of them may
become  subject  insofar as such  losses,  claims,  damages or  liabilities  (or
actions in respect  thereof) arise out of or are based upon any untrue statement
or alleged  untrue  statement of material  fact  contained  in the  Registration
Statement as originally  filed or in any amendment  thereof,  or any  prospectus
contained therein,  or in any amendment thereof or supplement  thereto, or arose
out of or are based upon the  omission or alleged  omission  to state  therein a
material fact required to be stated  therein or necessary to make the statements
therein not misleading,  and agrees to reimburse each such indemnified party, as
incurred,  for any  legal  or  other  expenses  reasonably  incurred  by them in
connection  with  investigating  or  defending  any such  loss,  claim,  damage,
liability or action;  provided that any such loss, claim,  damage,  liability or
expense arises out of or is based upon an untrue  statement or an omission or an
alleged  untrue  statement or an alleged  omission  made in reliance  upon or in
conformity   with   written   information   furnished  to  the  Company  by  the
Warrantholder or on behalf

                                     - 15 -

<PAGE>

of the  Warrantholder  expressly  for use in the  Registration  Statement or any
amendment  thereof  or any  prospectus  contained  therein  or in any  amendment
thereof or supplement thereto.

     E. Contribution. If the indemnification provided for herein from either the
Warrantholder  or the  Company  is  unavailable  to an  indemnified  party  (the
"Indemnitee") hereunder in respect of any losses, claims, damages or liabilities
(or actions in respect thereof)  referred to herein,  then the party responsible
for  such  indemnification  (the  "Indemnitor"),  in  lieu of  indemnifying  the
Indemnitee,  shall contribute to the amount paid or payable by the Indemnitee as
a result of such losses, claims, damages or liabilities in such proportion as is
appropriate  to reflect the relative  fault of the  Indemnitor and Indemnitee in
connection  with the actions which resulted in such losses,  claims,  damages or
liabilities  (including legal or other fees and expenses  reasonably incurred in
connection with any  investigation or proceeding) as well as any other equitable
considerations.

     If  indemnification  is available,  the  Indemnitor  shall  indemnify  each
Indemnitee to the full extent provided for herein without regard to the relative
fault of the  Indemnitor,  the Indemnitee or any other  equitable  consideration
provided for hereunder.

     F.  Securities  Exchange  Act.  After the  Registration  Statement  becomes
effective  and in  connection  with the sale of the  Warrants,  Common Stock and
Warrant Stock under such Registration  Statement,  the Warrantholder  shall take
such steps as may be  necessary to ensure that the offer and sale thereof are in
compliance with the requirements of the federal securities laws, including,  but
not  limited  to,  compliance  with the  anti-manipulation  requirements  of the
Securities Exchange Act of 1934, as amended (the "Exchange Act").

SECTION X.      NOTICES TO WARRANTHOLDERS.

     So long as this Warrant shall be  outstanding  and  unexercised  (a) if the
Company shall pay any dividend or make any distribution upon the Common Stock or
(b) if the Company  shall offer to the holders of Common Stock for  subscription
or purchase by them any shares of stock of any class or any other  rights or (c)
if any capital  reorganization of the Company,  reclassification  of the capital
stock of the  Company,  consolidation  or  merger  of the  Company  with or into
another corporation,  sale, lease or transfer of all or substantially all of the
assets of the Company to another  corporation,  or the voluntary or  involuntary
dissolution,  liquidation or winding up of the Company shall be effected,  then,
in any such case, the Company shall cause to be delivered to the  Warrantholder,
at least ten days prior to the date specified in (i) or (ii) below,  as the case
may be, a notice  containing  a brief  description  of the  proposed  action and
stating  the date on which (i) a record is to be taken for the  purpose  of such
dividend  or  distribution,  or  (ii)  such  reclassification,   reorganization,
consolidation, merger, conveyance, lease, dissolution, liquidation or winding up
is to take place and the date,  if any, as of which the holders of Common  Stock
of record  shall be  entitled  to  exchange  their  shares  of Common  Stock for
securities   or  other   property   deliverable   upon  such   reclassification,
reorganization,  consolidation,  merger, conveyance, dissolution, liquidation or
winding up.

                                     - 16 -

<PAGE>

SECTION XI.     NOTICES.

     Any notice pursuant to this Warrant by the Company or by the  Warrantholder
shall be in writing and shall be deemed to have been duly given if  delivered or
mailed certified mail, return receipt requested, (a) if to the Company, to it at
225 Belleville Avenue,  Bloomfield, New Jersey 07003, Attention: Chief Executive
Officer and (b) if to the  Warrantholder to the Warrantholder at the address set
forth on the  signature  page  hereto.  Each party  hereto may from time to time
change the address to which such  party's  notices are to be delivered or mailed
hereunder by notice in accordance herewith to the other party.

SECTION XII.    SUCCESSORS.

     All the covenants  and  provisions of this Warrant by or for the benefit of
the  Company or the  Warrantholder  shall bind and inure to the benefit of their
respective successors and assigns hereunder.

SECTION XIII.   APPLICABLE LAW.

     This  Warrant  shall be deemed to be a contract  made under the laws of the
State of Delaware  applicable to agreements made and to be performed entirely in
Delaware and for all purposes shall be construed in accordance with the internal
laws of Delaware  without  giving  effect to the  conflicts  of laws  principles
thereof.

SECTION XIV.    BENEFITS OF THIS WARRANT.

     Nothing  in this  Warrant  shall  be  construed  to give to any  person  or
corporation  other than the Company and the Warrantholder any legal or equitable
right, remedy or claim under this Warrant and this Warrant shall be for the sole
and exclusive benefit of the Company and the Warrantholder.

IN WITNESS WHEREOF, the parties hereto have executed this Warrant Certificate or
caused this Warrant Certificate to be duly executed as of the day and year first
above written.

ALFACELL CORPORATION

By:-----------------------
Name:
Title:

WARRANTHOLDER

-------------------------
Name:

Address:
--------------------------

--------------------------

--------------------------
Social Security Number

                                     - 17 -

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