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                                                                   EXHIBIT 10.11

               CONFIDENTIAL MATERIALS OMITTED AND FILED SEPARATELY
             WITH THE SECURITIES AND EXCHANGE COMMISSION. ASTERISKS
                                DENOTE OMISSIONS.

                              PUBLIC HEALTH SERVICE

                       PATENT LICENSE AGREEMENT--EXCLUSIVE

                                   COVER PAGE

For PHS internal use only:

     Patent License Number: [**]

     Serial Number(s) of Licensed Patent(s) and/or Patent Application(s):

            1)    U.S. Utility Patent Application No. [**].

            2)    U.S. Utility Patent Application No. [**].

     Licensee:    Millennium Pharmaceuticals, Inc.
                  75 Sidney Street
                  Cambridge, MA 02139

     Cooperative Research and Development AGREEMENT (CRADA) Number (if
     applicable): CRADA No. 0676

     Additional Remarks:  None

     Public Benefit(s): LICENSEE agrees, after its FIRST COMMERCIAL SALE, to
                        make reasonable quantities of LICENSED PRODUCT(S) or
                        materials produced through the use of LICENSED
                        PROCESS(ES) available on a compassionate use basis to
                        patients, either through the patient's physician(s)
                        and/or the medical center treating the patient; and

                        LICENSEE further agrees, after its FIRST COMMERCIAL SALE
                        and as part of its marketing and product promotion, to
                        develop written educational materials (e.g., brochures,
                        advertisements, etc.) directed to patients and
                        physicians detailing the LICENSED PRODUCT(S) and/or
                        medical aspects of using the LICENSED PRODUCT(S).

This Patent License Agreement, hereinafter referred to as the "AGREEMENT",
consists of this Cover Page, an attached AGREEMENT, a Signature Page, Appendix A
(List of Patent(s) and/or Patent Application(s)), Appendix B (Fields of Use and
Territory), Appendix C (Royalties), Appendix D (Modifications), Appendix E
(Benchmarks), and Appendix F (Commercial Development Plan). The Parties to this
Agreement are:

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             1)    The National Institutes of Health ("NIH"), the Centers for
                   Disease Control and Prevention ("CDC"), or the Food and Drug
                   Administration ("FDA"), hereinafter singly or collectively
                   referred to as "PHS", agencies of the United States Public
                   Health Service within the Department of Health and Human
                   Services ("DHHS"); and

             2)    The person, corporation, or institution identified above
                   and/or on the Signature Page, having offices at the address
                   indicated on the Signature Page, hereinafter referred to as
                   "LICENSEE".

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                    PHS PATENT LICENSE AGREEMENT -- EXCLUSIVE

                                    PREAMBLE

Whereas PHS and LICENSEE were parties to a Cooperative Research and Development
Agreement (CRADA) (CACR 0676) entered into in December 1998; and

Whereas in the course of performing biomedical research under the CRADA, PHS
investigators and employees of LICENSEE made certain inventions that resulted in
the filing of certain patent applications set forth in Appendix A; and

Whereas LICENSEE filed the patent application designated by Roman numeral I
listed in Appendix A; and

Whereas PHS filed the patent application designated by Roman numeral II listed
in Appendix A; and

Whereas PHS and LICENSEE intend to prosecute any claims under such patent
applications in accordance with the laws governing, and rules and regulations
of, the United States Patent and Trademark Office and to enter into this
agreement to promote the commercialization of said inventions.

Now, therefore, PHS and LICENSEE agree as follows:

1.   BACKGROUND

     1.01     In the course of conducting biomedical and behavioral research,
              PHS investigators made inventions that may have commercial
              applicability.

     1.02     By assignment of rights from PHS employees and other inventors,
              DHHS, on behalf of the United States Government, owns intellectual
              property rights claimed in any United States and/or foreign patent
              applications or patents corresponding to the assigned inventions.
              DHHS also owns any tangible embodiments of these inventions
              actually reduced to practice by PHS.

     1.03     The Secretary of DHHS has delegated to PHS the authority to enter
              into this AGREEMENT for the licensing of rights to these
              inventions.

     1.04     PHS desires to transfer these inventions to the private sector
              through commercialization licenses to facilitate the commercial
              development of products and processes for public use and benefit.

     1.05     LICENSEE desires to acquire commercialization rights to certain of
              these inventions in order to develop processes, methods, and/or
              marketable products for public use and benefit.

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2.   DEFINITIONS

     2.01     "BENCHMARKS" mean the performance milestones that are set forth in
              Appendix E.

     2.02     "COMMERCIAL DEVELOPMENT PLAN" means the written commercialization
              plan attached as Appendix F.

     2.03     "FIRST COMMERCIAL SALE" means the initial transfer by or on behalf
              of LICENSEE or its sublicenses of LICENSED PRODUCTS or the initial
              practice of a LICENSED PROCESS by or on behalf of LICENSEE or its
              sublicenses in exchange for cash or some equivalent to which value
              can be assigned for the purpose of determining NET SALES. Transfer
              of LICENSED PRODUCTS or practice of a LICENSED PROCESS for test
              marketing, sampling and promotional uses, clinical trial purposes
              or compassionate or similar use shall not be considered to
              constitute a FIRST COMMERCIAL SALE.

     2.04     "GOVERNMENT" means the Government of the United States of America.

     2.05     "LICENSED FIELDS OF USE" means the fields of use identified in
              Appendix B.

     2.06     "LICENSED FIELDS OF USE I" means the field of use identified in
              Appendix B with the Roman numeral I.

     2.07     "LICENSED FIELDS OF USE II" means the field of use identified in
              Appendix B with the Roman numeral II.

     2.08     "LICENSED PATENT RIGHTS" shall means DHHS' ownership interest in:

              (a)   Patent applications (including provisional patent
                    applications and PCT patent applications) and/or patents
                    listed in Appendix A, all divisions and continuations of
                    these applications, all patents issuing from such
                    applications, divisions, and continuations, and any
                    reissues, reexaminations, renewals and extensions (including
                    any Supplemental Patent Certificate) of all such patents,
                    and any confirmation patent, registration patent or patent
                    of addition of all such patents;

              (b)   to the extent that the following contain one or more claims
                    directed to the invention or inventions disclosed in a)
                    above: i) continuations-in-part of a) above; ii) all
                    divisions and continuations of these continuations-in-part;
                    iii) all patents issuing from such continuations-in-part,
                    divisions, and continuations; iv) priority patent
                    application(s) of a) above; and v) any reissues,
                    reexaminations renewals and extensions (including any
                    Supplemental Patent Certificate) of all such patents and any
                    confirmation patent, registration patent or patent of
                    addition of all such patents;

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              (c)   to the extent that the following contain one or more claims
                    directed to the invention or inventions disclosed in a)
                    above: all counterpart foreign and U.S. patent applications
                    and patents to a) and b) above, including those listed in
                    Appendix A.

              LICENSED PATENT RIGHTS shall not include b) or c) above to the
              extent that they contain one or more claims directed to new matter
              which is not the subject matter disclosed in a) above.

     2.09     "LICENSED PROCESS(ES)" means processes which, in the course of
              being practiced would be within the scope of one or more claims of
              the LICENSED PATENT RIGHTS that have not been held unpatentable,
              invalid or unenforceable by an unappealed or unappealable judgment
              of a court of competent jurisdiction.

     2.10     "LICENSED PRODUCT(S)" means tangible materials which, in the
              course of manufacture, use, sale, offer for sale or importation
              would be within the scope of one or more claims of the LICENSED
              PATENT RIGHTS that have not been held unpatentable, invalid or
              unenforceable by an unappealed or unappealable judgment of a court
              of competent jurisdiction.

     2.11     "LICENSED TERRITORY" means the geographical area identified in
              Appendix B.

     2.12     "NET SALES" means the total gross receipts for sales or other
              disposition of LICENSED PRODUCTS or practice of LICENSED PROCESSES
              by or on behalf of LICENSEE or its sublicenses, whether invoiced
              or not, less returns and allowances, packing costs, insurance
              costs, freight out, taxes or excise duties imposed on the
              transaction (if separately invoiced), wholesaler and cash
              discounts in amounts customary in the trade to the extent actually
              granted, and credits or allowances given or made for wastage
              replacement, indigent patient and any other sales programs. No
              deductions shall be made for commissions paid to individuals,
              whether they be with independent sales agencies or regularly
              employed by LICENSEE, or sublicenses, and on its payroll, or for
              the cost of collections.

     2.13     "PRACTICAL APPLICATION" means to manufacture in the case of a
              composition or product, to practice in the case of a process or
              method, or to operate in the case of a machine or system; and in
              each case, under such conditions as to establish that the
              invention is being utilized and that its benefits are to the
              extent permitted by law or GOVERNMENT regulations available to the
              public on reasonable terms.

     2.14     "Research License" means a nontransferable, nonexclusive license
              to practice the LICENSED PATENT RIGHTS for purposes of research
              and not for purposes of commercial manufacture or distribution or
              in lieu of purchase.

3.   GRANT OF RIGHTS

     3.01     PHS hereby grants and LICENSEE accepts, subject to the terms and
              conditions of this AGREEMENT, an exclusive license including the
              right to grant sublicenses,

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              under the LICENSED PATENT RIGHTS in the LICENSED TERRITORY, to
              make and have made, to use and have used, to sell and have sold,
              to offer to sell, and to import and have imported any LICENSED
              PRODUCTS in the LICENSED FIELDS OF USE I and to practice and have
              practiced any LICENSED PROCESSES in the LICENSED FIELDS OF USE I.

     3.02     PHS hereby grants and LICENSEE accepts, subject to the terms and
              conditions of this AGREEMENT, a nonexclusive license including the
              right to grant sublicenses, under the LICENSED PATENT RIGHTS in
              the LICENSED TERRITORY, to make and have made, to use and have
              used, to sell and have sold, to offer to sell, and to import and
              have imported any Licensed Products in the LICENSED FIELDS OF USE
              II and to practice and have practiced any Licensed Processes in
              the LICENSED FIELDS OF USE II.

     3.03     Except as expressly provided herein, this AGREEMENT confers no
              license or rights by implication, estoppel, or otherwise under any
              patent applications or patents of PHS or under any patent
              applications or patents of LICENSEE, other than the LICENSED
              PATENT RIGHTS, regardless of whether such patents are dominant or
              subordinate to LICENSED PATENT RIGHTS.

4.   SUBLICENSING

     4.01     Upon written approval by PHS, which approval will not be
              unreasonably withheld or delayed, LICENSEE may enter into
              sublicensing agreements under the LICENSED PATENT RIGHTS, provided
              that if LICENSEE has not received any written response from PHS
              within twenty (20) days of PHS's receipt of LICENSEE's written
              submission of a sublicense for approval, such approval shall be
              deemed to have been given.

     4.02     LICENSEE agrees that any sublicenses granted by it will provide
              that the obligations to PHS of Paragraphs 5.01-5.04, 8.01, 10.01,
              12.05, and 13.06-13.07 of this AGREEMENT shall be binding upon the
              sublicense as if it were a Party to this AGREEMENT. LICENSEE
              further agrees to attach copies of these Paragraphs to all
              sublicense agreements.

     4.03     Any sublicenses granted by LICENSEE shall provide for the
              termination of the sublicense, or the conversion to a license
              directly between such sublicenses and PHS, at the option of the
              sublicense, upon termination of this AGREEMENT under Article 13.
              Such conversion is subject to PHS approval, such approval not to
              be unreasonably withheld or delayed, and contingent upon
              acceptance by the sublicense of the remaining provisions of this
              AGREEMENT.

     4.04     LICENSEE agrees to forward to PHS a copy of each fully executed
              sublicense agreements postmarked within thirty (30) days of the
              execution of such agreements. To the extent permitted by law, PHS
              agrees to maintain each such sublicense agreements in confidence.

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5.   STATUTORY AND PHS REQUIREMENTS AND RESERVE GOVERNMENT RIGHTS

     5.01     (a) PHS reserves on behalf of the GOVERNMENT an irrevocable,
                  nonexclusive, nontransferable, royalty-free license to
                  practice all inventions licensed under the LICENSED PATENT
                  RIGHTS throughout the world by or on behalf of the GOVERNMENT
                  and on behalf of any foreign government or international
                  organization pursuant to any existing or future treaty or
                  agreement to which the GOVERNMENT is a signatory.

              (b) In the event that LICENSED PATENT RIGHTS are Subject
                  Inventions made under a Cooperative Research and Development
                  AGREEMENT (CRADA), LICENSEE grants to the GOVERNMENT, pursuant
                  to 15 U.S.C. Section 3710a(b)(1)(A), a nonexclusive,
                  nontransferable, irrevocable, paid-up license to practice
                  LICENSED PATENT RIGHTS or have LICENSED PATENT RIGHTS
                  practiced throughout the world by or on behalf of the
                  GOVERNMENT. In the exercise of such license, the GOVERNMENT
                  shall not publicly disclose trade secrets or commercial or
                  financial information that is privileged or confidential
                  within the meaning of 5 U.S.C. Section 552(b)(4) or which
                  would be considered as such if it had been obtained from a
                  non-Federal party.

     5.02     LICENSEE agrees that products used or sold in the United States
              embodying the LICENSED PATENT RIGHTS or produced through use of
              processes set forth in the LICENSED PATENT RIGHTS, but only to the
              extent LICENSEE does not otherwise have the right to manufacture
              such products in the absence of the licenses granted under this
              AGREEMENT, shall be manufactured substantially in the United
              States, unless a written waiver is obtained in advance from PHS.

     5.03     LICENSEE acknowledges that PHS may enter into future CRADAs under
              the Federal Technology Transfer Act of 1986 that relate to the
              subject matter of this AGREEMENT. LICENSEE agrees not to
              unreasonably deny requests for a RESEARCH LICENSE from such future
              collaborators with PHS when acquiring such rights is necessary in
              order to make a CRADA project feasible. LICENSEE may request an
              opportunity to join as a party to the proposed CRADA.

     5.04     (a) In addition to the reserved license of Paragraph 5.01 above,
                  PHS reserves the right to grant nonexclusive RESEARCH LICENSES
                  directly or to require LICENSEE to grant nonexclusive RESEARCH
                  LICENSES on reasonable terms. The purpose of this RESEARCH
                  LICENSE is to encourage basic research, whether conducted at
                  an academic or corporate facility. In order to safeguard the
                  LICENSED PATENT RIGHTS, however, PHS shall consult with
                  LICENSEE before granting to commercial entities a Research
                  License or providing to them research samples of materials
                  made through the LICENSED PROCESSES.

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              (b) In exceptional circumstances, and in the event that LICENSED
                  PATENT RIGHTS are Subject Inventions made under a CRADA, the
                  GOVERNMENT, pursuant to 15 U.S.C. Section 3710a(b)(1)(B),
                  retains the right to require the LICENSEE to grant to a
                  responsible applicant a nonexclusive, partially exclusive, or
                  exclusive sublicense to use LICENSED PATENT RIGHTS in the
                  LICENSED FIELD of Use I on terms that are reasonable under the
                  circumstances; or if LICENSEE fails to grant such a license,
                  the GOVERNMENT retains the right to grant the license itself.
                  The exercise of such rights by the GOVERNMENT' shall only be
                  in exceptional circumstances and only if the GOVERNMENT
                  determines (i) the action is necessary to meet health or
                  safety needs that are not reasonably satisfied by LICENSEE;
                  (ii) the action is necessary to meet requirements for public
                  use specified by Federal regulations, and such requirements
                  are not reasonably satisfied by the LICENSEE; or (iii) the
                  LICENSEE has failed to comply with an agreement containing
                  provisions described in 15 U.S.C. Section 3710a(c)(4)(B). The
                  determination made by the GOVERNMENT under this Article is
                  subject to administrative appeal and judicial review under 35
                  U.S.C. Section 203(2).

6.   ROYALTIES AND REIMBURSEMENT

     6.01     LICENSEE agrees to pay to PHS a noncreditable, nonrefundable
              license issue royalty as set forth in Appendix C.

     6.02     LICENSEE agrees to pay to PHS a nonrefundable minimum annual
              royalty as set forth in Appendix C, if any. The minimum annual
              royalty is due and payable on January 1 of each calendar year and
              may be credited against any earned royalties due for sales made in
              that year. The minimum annual royalty due for the first calendar
              year of this AGREEMENT may be prorated according to the fraction
              of the calendar year remaining between the effective date of this
              AGREEMENT and the next subsequent January 1.

     6.03     LICENSEE agrees to pay PHS earned royalties as set forth in
              Appendix C.

     6.04     LICENSEE agrees to pay PHS benchmark royalties as set forth in
              Appendix C.

     6.05     LICENSEE agrees to pay PHS sublicensing royalties as set forth in
              Appendix C.

     6.06     A patent or patent application licensed under this AGREEMENT shall
              cease to fall within the LICENSED PATENT RIGHTS for the purpose of
              computing earned royalty payments in any given country on the
              earliest of the dates that a) the application has been abandoned
              and not continued, b) the patent expires or irrevocably lapses, c)
              the claim has been held to be invalid or unenforceable by an
              unappealed or unappealable decision of a court of competent
              jurisdiction or administrative agency, or (d) the claim has been
              pending, in prosecution by PHS, for more then eight (8) years,
              except that such eight (8) year period shall be extended by any
              period during which examination of the claim is interrupted by (a)
              an interference

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              proceeding under 35 U.S.C. Section 135 or (b) the claim is under
              appeal by PHS from the decision of an examiner pursuant to 37
              C.F.R. 1.; provided that if the claim subsequently issues, it
              shall be deemed to fall within and shall be a claim under the
              LICENSED PATENT RIGHTS, on which royalties are due.

     6.07     No multiple royalties shall be payable because any LICENSED
              PRODUCTS or LICENSED PROCESSES are covered by more than one of the
              LICENSED PATENT RIGHTS.

     6.08     On sales of LICENSED PRODUCTS by LICENSEE to sublicenses or on
              sales made in other than an arm's-length transaction, the value of
              the NET SALES attributed under this Article 6 to such a
              transaction shall be that which would have been received in an
              arm's-length transaction, based on sales of like quantity and
              quality products on or about the time of such transaction.

     6.09     With regard to expenses associated with the preparation, filing,
              prosecution, and maintenance of all patent applications and
              patents included within the LICENSED PATENT RIGHTS incurred by PHS
              prior to the effective date of this AGREEMENT, LICENSEE shall pay
              to PHS, as an additional royalty, within sixty (60) days of PHS's
              submission of a statement and request for payment to LICENSEE, an
              amount equivalent to such patent expenses previously incurred by
              PHS.

     6.10     With regard to expenses associated with the preparation, filing,
              prosecution, and maintenance of all patent applications and
              patents included within the LICENSED PATENT RIGHTS incurred by PHS
              on or after the effective date of this AGREEMENT LICENSEE agrees:

              (a) to pay PHS on an annual basis, within sixty (60) days of PHS's
                  submission of a statement and request for payment, a royalty
                  amount equivalent to all such patent expenses incurred during
                  the previous calendar year(s); or

              (b) to pay such expenses directly to the law firm employed by PHS
                  to handle such functions. However, in such event, PHS and not
                  LICENSEE shall be the client of such law firm.

     6.11     LICENSEE may elect to surrender its license to PHS's interest in
              the LICENSED PATENT RIGHTS in any country of the LICENSED
              TERRITORY upon ninety (90) days written notice to PHS. In such
              case, PHS shall have the right, but not the obligation, to
              continue the prosecution and maintenance of such patent
              applications or patents in such country included within the
              LICENSED PATENT RIGHTS, at its sole expense.

7.   PATENT FILING, PROSECUTION, AND MAINTENANCE

     7.01     (a) Prior to the date this AGREEMENT becomes effective, PHS has
                  been responsible for the prosecution of the Patent Application
                  No. II in

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              Appendix A and LICENSEE has been responsible for the preparation,
              filing and prosecution of Patent Application No. I in Appendix A,
              each at its sole expense. After the effective date of this
              AGREEMENT, PHS shall be responsible for the preparation, filing,
              prosecution and maintenance of any and all patent applications or
              patents included in the LICENSED PATENT RIGHTS at LICENSEE's sole
              expense and shall on an ongoing basis promptly furnish copies of
              all patent-related documents to LICENSEE. Notwithstanding the
              foregoing, on a country-by-country basis, LICENSEE shall have the
              right to elect not to be responsible for expenses pursuant to this
              Section 7.01(a) with respect to any patent applications or patents
              included in the LICENSED PATENT RIGHTS, with the understanding
              that if LICENSEE makes such an election, the worldwide license
              granted in Paragraphs 3.01 and 3.02 shall exclude the specific
              patent applications or patents for which LICENSEE has made such
              election in such country. PHS shall select registered patent
              attorneys or patent agents to provide patent-related services
              related to the LICENSED PATENT RIGHTS, reasonably acceptable to
              LICENSEE. LICENSEE shall provide appropriate powers of attorney
              and other documents necessary to undertake such actions to the
              patent attorneys or patent agents providing such services. PHS and
              its attorneys or agents shall provide LICENSEE sufficient
              opportunity to comment on any document that PHS intends to file or
              to cause to be filed with the relevant intellectual property or
              patent office.

        (b)   PHS shall have the right and responsibility to prosecute and
              maintain patent prosecution for all LICENSED PATENT RIGHTS.
              LICENSEE shall make available to PHS or its authorized attorneys,
              agents or representatives, such of its employees whom PHS in its
              reasonable judgment deems necessary in order to assist it in
              obtaining patent protection for such LICENSED PATENT RIGHTS.
              LICENSEE shall provide appropriate powers of attorney and other
              documents necessary to undertake such actions to the patent
              attorneys or patent agents providing such services. PHS and its
              attorneys or agents shall provide LICENSEE sufficient opportunity
              to comment on any document that PHS intends to file or to cause to
              be filed with the relevant intellectual property or patent office.

        (c)   In the event PHS elects not to file or continue to seek or
              maintain patent protection on any LICENSED PATENT RIGHTS. LICENSEE
              shall have the right, at its sole expense, to prosecute and
              maintain in any country patent protection on such LICENSED PATENT
              RIGHTS in PHS's name. In any such case, PHS shall make available
              to LICENSEE or its authorized attorneys, agents or
              representatives, such of its employees whom LICENSEE in its
              reasonable judgment deems necessary in order to assist it in
              obtaining patent protection for such LICENSED PATENT RIGHTS.
              LICENSEE and its attorneys or agents shall provide PHS sufficient
              opportunity to comment on any document that LICENSEE intends to
              file or to cause to be filed with the relevant intellectual
              property or patent office.

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     7.02     Each Party shall promptly inform the other as to all matters that
              come to its attention that may affect the preparation, filing,
              prosecution or maintenance of the LICENSED PATENT RIGHTS and
              permit each other to provide comments and suggestion with respect
              to the preparation, filing, prosecution and maintenance of
              LICENSED PATENT RIGHTS, which comments and suggestions shall be
              considered by the other Party.

8.   RECORD KEEPING

     8.01     LICENSEE agrees to keep accurate and correct records of LICENSED
              PRODUCTS made, used, sold, or imported and LICENSED PROCESSES
              practiced under this AGREEMENT appropriate to determine the amount
              of royalties due PHS. Such records shall be retained for at least
              five (5) years following a given reporting period and shall be
              available, not to exceed once during each calendar year, during
              the term of this agreement, during normal business hours for
              inspection at the expense of PHS by an accountant or other
              designated auditor selected by PHS for the sole purpose of
              verifying reports and payments hereunder. Any such accountant or
              auditor shall be reasonably acceptable to LICENSEE and shall
              execute a standard form of confidentiality agreement with
              LICENSEE. The accountant or auditor shall only disclose to PHS
              information relating to the accuracy of reports and payments made
              under this AGREEMENT. If an inspection shows an underreporting or
              underpayment in excess of five percent (5%) for any twelve (12)
              month period, then LICENSEE shall reimburse PHS for the cost of
              the inspection at the time LICENSEE pays the unreported royalties,
              including any late charges as required by Paragraph 9.08 of this
              AGREEMENT. All payments required under this Paragraph shall be due
              within thirty (30) days of the date PHS provides LICENSEE notice
              of the payment due.

     8.02     LICENSEE agrees to have an audit of sales and royalties conducted
              by an independent auditor at least every two (2) years if annual
              sales of the LICENSED PRODUCT or LICENSED PROCESSES are over
              fifteen (15) million dollars. The audit shall address, at a
              minimum, the amount of gross sales by or on behalf of LICENSEE
              during the audit period, terms of the license as to percentage or
              fixed royalty to be remitted to the GOVERNMENT, the amount of
              royalty funds owed to the GOVERNMENT under this AGREEMENT, and
              whether the royalty amount owed has been paid to the GOVERNMENT
              and is reflected in the records of the LICENSEE. The audit shall
              also indicate the PHS license number, product, and the time period
              being audited. A report certified by the auditor shall be
              submitted promptly by the auditor directly to PHS on completion.
              LICENSEE shall pay for the entire cost of the audit.

9.   REPORTS ON PROGRESS, BENCHMARKS, SALES, AND PAYMENTS

     9.01     Prior to signing this AGREEMENT, LICENSEE has provided to PHS the
              COMMERCIAL DEVELOPMENT PLAN at Appendix F, under which LICENSEE
              intends to bring the subject matter of the LICENSED PATENT RIGHTS
              to the point of PRACTICAL APPLICATION. This COMMERCIAL DEVELOPMENT
              PLAN is hereby incorporated by

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              reference into this AGREEMENT. Based on this plan, performance
              BENCHMARKS are determined as specified in Appendix E.

     9.02     LICENSEE shall provide written annual reports on its product
              development progress or efforts to commercialize LICENSED PRODUCTS
              under the COMMERCIAL DEVELOPMENT PLAN within sixty (60) days after
              December 31 of each calendar year. These progress reports shall
              include progress on research and development, status of
              applications for regulatory approvals, manufacturing,
              sublicensing, marketing, importing, and sales during the preceding
              calendar year, as well as plans for the present calendar year. PHS
              also encourages these reports to include information on any of
              LICENSEE's public service activities that relate to the LICENSED
              PATENT RIGHTS. If reported progress differs from that projected in
              the COMMERCIAL DEVELOPMENT PLAN and BENCHMARKS, LICENSEE shall
              explain the reasons for such differences. In any such annual
              report, LICENSEE may propose amendments to the COMMERCIAL
              DEVELOPMENT PLAN, acceptance of which by PHS may not be denied
              unreasonably. LICENSEE may amend the BENCHMARKS at any time upon
              written consent by PHS. PHS shall not unreasonably withhold
              approval of any request of LICENSEE to extend the time periods of
              this schedule if such request is supported by a reasonable showing
              by LICENSEE of diligence in its performance under the COMMERCIAL
              DEVELOPMENT PLAN and toward bringing the LICENSED PATENT RIGHTS to
              the point of PRACTICAL APPLICATION as defined in 37 C.F.R.
              404.3(d). LICENSEE shall amend the COMMERCIAL DEVELOPMENT PLAN and
              BENCHMARKS at the reasonable request of PHS to address any
              LICENSED PRODUCTS not specifically addressed in the plan
              originally submitted.

     9.03     LICENSEE shall report to PHS the dates for achieving BENCHMARKS
              specified in Appendix E and the FIRST COMMERCIAL SALE in each
              country in the LICENSED TERRITORY within thirty (30) days of such
              occurrences.

     9.04     Commencing with the calendar half year in which the FIRST
              COMMERCIAL SALE of a LICENSED PRODUCT occurs, LICENSEE shall
              submit to PHS within sixty (60) days after each calendar half-year
              ending June 30 and December 31, a royalty report setting forth for
              the preceding half-year period the amount of the LICENSED PRODUCTS
              sold or LICENSED PROCESSES practiced by or on behalf of LICENSEE
              in each country within the LICENSED TERRITORY, the NET SALES, and
              the amount of royalty accordingly due. With each such royalty
              report, LICENSEE shall submit payment of the earned royalties due.
              If no earned royalties are due to PHS for any reporting period,
              the written report shall so state. The royalty report shall be
              certified as correct by an authorized representative, officer, the
              Vice President of Finance or the controller of LICENSEE, and shall
              include a detailed listing of all deductions made under Paragraph
              2.10 and such other information relevant to the calculation of NET
              SALES made under Article 6 to determine royalties due.

     9.05     LICENSEE agrees to forward, upon request, semi-annually to PHS a
              copy of such reports received by LICENSEE from its sublicenses
              during the preceding half-year

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              period as shall be pertinent to a royalty accounting to PHS by
              LICENSEE for activities under the sublicense.

     9.06     Royalties due under Article 6 shall be paid in U.S. dollars. For
              conversion of foreign currency to U.S. dollars, the conversion
              rate shall be the New York foreign exchange rate quoted in THE
              WALL STREET JOURNAL on the day that the payment is due. All checks
              and bank drafts shall be drawn on United States banks and shall be
              payable, as appropriate, to "NIH/Patent Licensing." All such
              payments shall be sent to the following address: NIH, P.O. Box
              360120, Pittsburgh, PA 15251-6120. Any loss of exchange, value,
              taxes, or other expenses incurred in the transfer or conversion to
              U.S. dollars shall be paid entirely by LICENSEE. The royalty
              report required by Paragraph 9.04 of this AGREEMENT shall
              accompany each such payment, and a copy of such report shall also
              be mailed to PHS at its address for notices indicated on the
              Signature Page of this AGREEMENT.

     9.07     LICENSEE shall be solely responsible for determining if any tax on
              royalty income is owed outside the United States and shall pay any
              such tax and be responsible for all filings with appropriate
              agencies of foreign Governments.

     9.08     Interest and penalties may be assessed by PHS on any overdue
              payments in accordance with the Federal Debt Collection Act. The
              payment of such late charges shall not prevent PHS from exercising
              any other rights it may have as a consequence of the lateness of
              any payment.

     9.09     All plans, reports, and information required by Articles 7 or 8 or
              this Article 9 and marked "confidential" by LICENSEE shall, to the
              extent permitted by law, be treated by PHS as commercial and
              financial information obtained from a person and as privileged and
              confidential, and any proposed disclosure of such records by the
              PHS under the Freedom of Information Act (FOIA), 5 U.S.C.; Section
              552 shall be subject to the predisclosure notification
              requirements of 45 C.F.R. Section 5.65(d).

10.  PERFORMANCE

     10.01    LICENSEE shall use commercially reasonable efforts to bring the
              LICENSED PRODUCTS and LICENSED PROCESSES to PRACTICAL APPLICATION.
              "Commercially reasonable efforts" for the purposes of this
              provision shall include adherence to the COMMERCIAL DEVELOPMENT
              PLAN at Appendix F and performance of the BENCHMARKS at Appendix
              E. The efforts of a sublicense shall be considered the efforts of
              LICENSEE.

     10.02    Upon the FIRST COMMERCIAL SALE, until the expiration of this
              AGREEMENT, LICENSEE shall use commercially reasonable efforts to
              make LICENSED PRODUCTS and LICENSED PROCESSES reasonably
              accessible to the United States public.

     10.03    LICENSEE agrees, after its FIRST COMMERCIAL SALE, to make
              reasonable quantities of LICENSED PRODUCT(S) or materials produced
              through the use of LICENSED

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              PROCESS(ES) available on a compassionate use basis to patients,
              either through the patient's physician(s) and/or the medical
              center treating the patient.

     10.04    LICENSEE further agrees, after its FIRST COMMERCIAL SALE and as
              part of its marketing and product promotion, to develop written
              educational materials (e.g., brochures, advertisements, etc.)
              directed to patients and physicians detailing the LICENSED
              PRODUCT(S) and/or medical aspects of using the LICENSED
              PRODUCT(S).

11.  INFRINGEMENT AND PATENT ENFORCEMENT

     11.01    PHS and LICENSEE agree to notify each other promptly of each
              infringement or possible infringement of the LICENSED PATENT
              RIGHTS, as well as any facts which may affect the validity, scope,
              or enforceability of the LICENSED PATENT RIGHTS of which either
              Party becomes aware.

     11.02    Pursuant to this AGREEMENT and the provisions of Chapter 29 of
              title 35, United States Code, LICENSEE shall have: a) the first
              right to bring suit in its own name, at its own expense, and on
              its own behalf for infringement of the LICENSED PATENT RIGHTS; b)
              the right in any such suit to enjoin infringement and collect for
              its use, damages, profits, and awards of whatever nature
              recoverable for such infringement; and c) the right to settle any
              claim or suit for infringement of the LICENSED PATENT RIGHTS,
              subject to approval by the U.S. Government. If LICENSEE desires to
              initiate a suit for patent infringement, LICENSEE shall notify PHS
              in writing. If LICENSEE fails to initiate such suit or action
              within ninety (90) days of a written notice by PHS requesting that
              LICENSEE initiate infringement proceedings, PHS shall have the
              right to initiate such action. LICENSEE shall have a continuing
              right to intervene or join in such suit. LICENSEE shall take no
              action to compel the GOVERNMENT either to initiate or to join in
              any such suit for patent infringement. LICENSEE may request the
              GOVERNMENT to initiate or join in any such suit if necessary to
              avoid dismissal of the suit. Should the GOVERNMENT be made a party
              to any such suit, LICENSEE shall reimburse the GOVERNMENT for any
              costs, expenses, or fees which the GOVERNMENT incurs as a result
              of such motion or other action, including any and all costs
              incurred by the GOVERNMENT in opposing any such motion or other
              action. In all cases, LICENSEE agrees to keep PHS reasonably
              apprised of the status and progress of any litigation brought by
              LICENSEE and PHS agrees to keep LICENSEE reasonably apprised of
              the status and progress of any litigation brought by PHS. Before
              LICENSEE commences an infringement action, LICENSEE shall notify
              PHS and give careful consideration to the views of PHS and to any
              potential effects of the litigation on the public health in
              deciding whether to bring suit.

     11.03    In the event that a declaratory judgment action alleging
              invalidity or non-infringement of any of the LICENSED PATENT
              RIGHTS shall be brought against LICENSEE or raised by way of
              counterclaim or affirmative defense in an infringement suit
              brought by LICENSEE under Paragraph 11.02, pursuant to this
              AGREEMENT and the provisions of Chapter 29 of Title 35, United
              States Code or other statutes, LICENSEE may: a) defend the suit in
              its own name, at its own

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              expense, and on its own behalf; b) in any such suit, ultimately to
              enjoin infringement and to collect for its use, damages, profits,
              and awards of whatever nature recoverable for such infringement;
              and c) settle any claim or suit for declaratory judgment involving
              the LICENSED PATENT RIGHTS-provided, however, that PHS and
              appropriate GOVERNMENT authorities shall have a continuing right
              to join in such suit. Except where the Government is a legally
              necessary party, LICENSEE shall take no action to compel the
              GOVERNMENT either to initiate or to join in any such declaratory
              judgment action. LICENSEE may request the GOVERNMENT to initiate
              or to join any such suit if necessary to avoid dismissal of the
              suit. Should the GOVERNMENT be made a party to any such suit by
              motion or any other action of LICENSEE, LICENSEE shall reimburse
              the GOVERNMENT for any reasonable costs, expenses, or fees which
              the GOVERNMENT incurs as a result of such motion or other action.
              If LICENSEE elects not to defend against such declaratory judgment
              action, PHS, at its option, may do so at its own expense. In all
              cases, LICENSEE agrees to keep PHS reasonably apprised of the
              status and progress of any litigation. Before LICENSEE commences
              an infringement action, LICENSEE shall notify PHS and give careful
              consideration to the views of PHS and to any potential effects of
              the litigation on the public health in deciding whether to bring
              suit.

     11.04    In any action under Paragraphs 11.02 or 11.03, the expenses
              including costs, fees, attorney fees, and disbursements, shall be
              paid by LICENSEE. The value of any recovery made by LICENSEE
              through court judgment or settlement shall be treated as NET SALES
              and subject to earned royalties.

     11.05    PHS shall cooperate fully with LICENSEE in connection with any
              action under Paragraphs 11.02 or 11.03. PHS agrees promptly to
              provide access to all necessary documents and relevant existing
              employees, pursuant to 45 C.F.R. Part 2 and to render reasonable
              assistance in response to a request by LICENSEE.

12.  NEGATION OF WARRANTIES AND INDEMNIFICATION

     12.01    PHS offers no warranties other than those specified in Article 1.

     12.02    PHS does not warrant the validity of the LICENSED PATENT RIGHTS
              and makes no representations whatsoever with regard to the scope
              of the LICENSED PATENT RIGHTS, or that the LICENSED PATENT RIGHTS
              may be exploited without infringing other patents or other
              intellectual property rights of third parties.

     12.03    PHS MAKES NO WARRANTIES, EXPRESSED OR IMPLIED, OF MERCHANTABILITY
              OR FITNESS FOR A PARTICULAR PURPOSE OF ANY SUBJECT MATTER DEFINED
              BY THE CLAIMS OF THE LICENSED PATENT RIGHTS OR TANGIBLE MATERIALS
              RELATED THERETO.

     12.04    PHS does not represent that it will commence legal actions against
              third parties infringing the LICENSED PATENT RIGHTS.

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     12.05    LICENSEE shall indemnify and hold PHS, its employees, students,
              fellows, agents, and consultants harmless from and against all
              liability, demands, damages, expenses, and losses, including but
              not limited to death, personal injury, illness, or property damage
              in connection with or arising out of: a) the use by or on behalf
              of LICENSEE, its sublicenses, directors, or employees, of any
              LICENSED PATENT RIGHTS; or b) the design, manufacture,
              distribution, or use of any LICENSED PRODUCTS, LICENSED PROCESSES
              or materials by LICENSEE or its sublicenses, or other products or
              processes developed through the practice of the LICENSED PATENT
              RIGHTS, unless such liability, demands, damages, expenses or
              losses are due to the gross negligence or willful misconduct of
              PHS, its employees, students, fellows, agents or consultants.
              LICENSEE agrees to maintain a liability insurance program
              consistent with sound business practice.

13.  TERM, TERMINATION, AND MODIFICATION OF RIGHTS

     13.01    This AGREEMENT is effective when signed by all Parties (the
              "effective date") and shall extend to the expiration of the last
              to expire of the LICENSED PATENT RIGHTS unless sooner terminated
              as provided in this Article 13.

     13.02    The terms and conditions of this AGREEMENT shall be considered by
              PHS to be withdrawn from LICENSEE's consideration and the terms
              and conditions of this AGREEMENT and the AGREEMENT itself to be
              null and void, unless this AGREEMENT is executed within sixty (60)
              days from the date of printing indicated at the bottom of each
              page.

     13.03    Except as otherwise provided in Section 13.05, in the event that
              LICENSEE is in default in performance of any material obligation
              under this AGREEMENT, and if the default has not been remedied
              within ninety (90) days after the date of notice in writing of
              such default, PHS may terminate this AGREEMENT by written notice
              and pursue outstanding amounts owed through procedures provided by
              the Federal Debt Collection Act.

     13.04    LICENSEE shall have a unilateral right to terminate this
              AGREEMENT, any of the LICENSED FIELDS OF USE in Appendix B and/or
              any licenses in any country or territory by giving PHS sixty (60)
              days written notice to that effect. Upon any such termination by
              LICENSEE, LICENSEE and PHS shall each have, in the relevant
              country or territory, the right to practice the subject matter
              covered by the LICENSED PATENT RIGHTS determined under United
              States Patent Law to be jointly owned by the Parties and to
              license their respective ownership rights to others in all fields,
              countries or territories not covered by this AGREEMENT.

     13.05    Solely to the extent expressly authorized under 37 C.F.R. Section
              404.5(b)(9), PHS shall specifically have the right to terminate or
              modify, at its option, this AGREEMENT, if PHS determines that the
              LICENSEE: 1) is not executing the COMMERCIAL DEVELOPMENT PLAN
              submitted with its request for a license and the LICENSEE cannot
              otherwise demonstrate to PHS's satisfaction that the LICENSEE has
              taken, or can be expected to take within a reasonable time,
              effective steps to

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              achieve PRACTICAL APPLICATION of the LICENSED PRODUCTS or LICENSED
              PROCESSES; 2) has not performed its obligations under Section
              10.01 to achieve the BENCHMARKS as may be modified under Paragraph
              9.02; 3) has willfully made a false statement of, or willfully
              omitted, a material fact in the license application or in any
              report required by the license AGREEMENT; 4) has committed a
              material breach of a covenant or agreement contained in the
              license; 5) is not keeping LICENSED PRODUCTS or LICENSED PROCESSES
              reasonably available to the public after the commercial use
              commences; or 6) cannot reasonably justify a failure to comply
              with the domestic production requirement of Paragraph 5.04 unless
              waived. In making this determination, PHS shall take into account
              the normal course of similar commercial development programs
              conducted with sound and commercially reasonable business
              practices and judgment and the annual reports submitted by
              LICENSEE under Paragraph 9.02, and shall not impose more stringent
              performance obligations on LICENSEE than PHS customarily imposes
              on other PHS licensees in respect of patent licenses pertaining to
              human therapeutic products. Prior to invoking this right, PHS
              shall give written notice to LICENSEE providing LICENSEE specific
              notice of, and a ninety (90) day opportunity to respond to, PHS's
              concerns as to the previous items 1) to 6). If LICENSEE fails to
              alleviate PHS's concerns as to the previous items 1) to 6) or
              fails to initiate commercially reasonable corrective action to
              PHS's reasonable satisfaction, PHS may terminate or modify, at its
              option, this AGREEMENT.

     13.06    When the public health and safety so require, and after written
              notice to LICENSEE providing LICENSEE a sixty (60) day opportunity
              to respond, PHS shall have the right to require LICENSEE to grant
              sublicenses to responsible applicants, on reasonable terms, in
              LICENSED FIELDS OF USE I under the LICENSED PATENT RIGHTS, unless
              LICENSEE can reasonably demonstrate that the granting of the
              sublicense would not materially increase the availability to the
              public of the subject matter of the LICENSED PATENT RIGHTS. PHS
              will not require the granting of a sublicense unless the
              responsible applicant has first negotiated in good faith with
              LICENSEE.

     13.07    PHS reserves the right according to 37 C.F.R. Section 404.5(b)(9)
              to terminate or modify this AGREEMENT if it is determined that
              such action is necessary to meet requirements for public use
              specified by federal regulations issued after the date of the
              license and such requirements are not reasonably satisfied by
              LICENSEE.

     13.08    Within thirty (30) days of receipt of written notice of PHS's
              unilateral decision to modify or terminate this AGREEMENT,
              LICENSEE may, consistent with the provisions of 37 C.F.R. 404.11,
              appeal the decision by written submission to the designated PHS
              official. The decision of the designated PHS official shall be the
              final agency decision. LICENSEE may thereafter exercise any and
              all administrative or judicial remedies that may be available.

     13.09    Within ninety (90) days of expiration or termination of this
              AGREEMENT under this Article 13, a final report shall be submitted
              by LICENSEE. Any royalty payments, including those incurred but
              not yet paid, and those related to patent expense, due

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              to PHS shall become immediately due and payable upon termination
              or expiration. If terminated under this Article 13, sublicenses
              may elect to convert their sublicenses to direct licenses with PHS
              pursuant to Paragraph 4.03. Unless otherwise specifically provided
              for under this AGREEMENT, upon termination or expiration of this
              AGREEMENT, LICENSEE shall have the right to sell or otherwise
              transfer all LICENSED PRODUCTS or other materials included within
              the LICENSED PATENT RIGHTS in its possession subject to the
              royalty obligations of Appendix C.

14.  GENERAL PROVISIONS

     14.01    Neither Party may waive or release any of its rights or interests
              in this AGREEMENT except in writing. The failure of the GOVERNMENT
              or LICENSEE to assert a right hereunder or to insist upon
              compliance with any term or condition of this AGREEMENT shall not
              constitute a waiver of that right by the GOVERNMENT or LICENSEE,
              as the case may be, or excuse a similar subsequent failure to
              perform any such term or condition by LICENSEE or the GOVERNMENT,
              as the case may be.

     14.02    This AGREEMENT, together with CRADA CACR-0676, constitutes the
              entire agreement between the Parties relating to the LICENSED
              PATENT RIGHTS, and all prior negotiations, representations,
              agreements, and understandings are merged into, extinguished by,
              and completely expressed by this AGREEMENT.

     14.03    The provisions of this AGREEMENT are severable, and in the event
              that any provision of this AGREEMENT shall be determined to be
              invalid or unenforceable under any controlling body of law, such
              determination shall not in any way affect the validity or
              enforceability of the remaining provisions of this AGREEMENT.

     14.04    If either Party desires a modification to this AGREEMENT, the
              Parties shall, upon reasonable notice of the proposed modification
              by the Party desiring the change, confer in good faith to
              determine the desirability of such modification. No modification
              will be effective until a written amendment is signed by the
              signatories to this AGREEMENT or their designees.

     14.05    The construction, validity, performance, and effect of this
              AGREEMENT shall be governed by Federal law as applied by the
              Federal courts in the District of Columbia.

     14.06    All notices required or permitted by this AGREEMENT shall be given
              by prepaid, first class, registered or certified mail or by an
              express/overnight delivery service provided by a commercial
              carrier, properly addressed to the other Party at the address
              designated on the following Signature Page, or to such other
              address as may be designated in writing by such other Party.
              Notices shall be considered timely if such notices are received on
              or before the established deadline date or sent on or before the
              deadline date as verifiable by U.S. Postal Service postmark or
              dated receipt from a commercial carrier. Parties should request a
              legibly dated U.S. Postal Service postmark or obtain a dated
              receipt from a commercial carrier

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              or the U.S. Postal Service. Private metered postmarks shall not be
              acceptable as proof of timely mailing.

     14.07    This AGREEMENT shall not be assigned by LICENSEE except: a) with
              the prior written consent of PHS, such consent not to be withheld
              unreasonably; or b) as part of a sale or transfer of substantially
              the entire business of LICENSEE relating to operations which
              concern this AGREEMENT. LICENSEE shall notify PHS within ten (10)
              days of any assignment of this AGREEMENT by LICENSEE.

     14.08    LICENSEE acknowledges that it is subject to and agrees to abide by
              the United States laws and regulations (including the Export
              Administration Act of 1979 and Arms Export Control Act)
              controlling the export of technical data, computer software,
              laboratory prototypes, biological material, and other commodities.
              The transfer of such items may require a license from the
              cognizant Agency of the U.S. GOVERNMENT or written assurances by
              LICENSEE that it shall not export such items to certain foreign
              countries without prior approval of such agency. PHS neither
              represents that a license is or is not required or that, if
              required, it shall be issued.

     14.09    Except where written notice pursuant to 35 U.S.C. Section 287(a)
              is customarily used for enforcement of patent rights in the
              pharmaceutical industry, LICENSEE agrees to: (a) mark LICENSED
              PRODUCTS or their packaging sold in the United States with all
              U.S. patent numbers corresponding to the LICENSED PATENT RIGHTS
              and similarly to indicate "Patent Pending" status, and (b) mark
              all LICENSED PRODUCTS manufactured in, shipped to, or sold in
              other countries in such a manner as to preserve PHS patent rights
              in such countries.

     14.10    By entering into this AGREEMENT, PHS does not directly or
              indirectly endorse any product or service provided, or to be
              provided, by LICENSEE whether directly or indirectly related to
              this AGREEMENT. LICENSEE shall not state or imply that this
              AGREEMENT is an endorsement by the GOVERNMENT, PHS, any other
              GOVERNMENT organizational unit, or any GOVERNMENT employee.
              Additionally, LICENSEE shall not use the names of NIH, CDC, PHS,
              or DHHS or the GOVERNMENT or their employees in any advertising,
              promotional, or sales literature without the prior written consent
              of PHS. PHS shall not use the name, logo, trademark or any
              identification of LICENSEE for purposes of advertising or
              promotion without the prior written consent of LICENSEE.

     14.11    The Parties agree to attempt to settle amicably any controversy or
              claim arising under this AGREEMENT or a breach of this AGREEMENT,
              except for appeals of modifications or termination decisions
              provided for in Article 13 or determinations made by the
              GOVERNMENT under Paragraph 5.04. LICENSEE agrees first to appeal
              any such unsettled claims or controversies to the designated PHS
              official, or designee, whose decision shall be considered the
              final agency decision. Thereafter, LICENSEE may exercise any
              administrative or judicial remedies that may be available.

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     14.12    Nothing relating to the grant of a license, nor the grant itself,
              shall be construed to confer upon any person any immunity from or
              defenses under the antitrust laws or from a charge of patent
              misuse, and the acquisition and use of rights pursuant to 37
              C.F.R. Part 404 shall not be immunized from the operation of state
              or Federal law by reason of the source of the grant.

     14.13    Paragraphs 4.04, 8.01, 9.05-9.07, 9.09, 12.01-12.05, 13.08, 13.09
              and 14.12 of this AGREEMENT shall survive termination of this
              AGREEMENT.

                          SIGNATURES BEGIN ON NEXT PAGE

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                    PHS PATENT LICENSE AGREEMENT - EXCLUSIVE

                                 SIGNATURE PAGE

For PHS:

     /s/ Jack Spiegel                                        11/25/2002
----------------------                                       ------------
Jack Spiegel, Ph.D.                                          Date
Director, Division of Technology Development and Transfer
Office of Technology Transfer
National Institutes of Health

Mailing Address for Notices:

Office of Technology Transfer
National Institutes of Health
6011 Executive Boulevard, Suite 325
Rockville, Maryland 20852-3804 U.S.A.

For LICENSEE (Upon, information and belief, the undersigned expressly certifies
or affirms that the contents of any statements of LICENSEE made or referred to
in this document are truthful and accurate.):

by:

     /s/Kevin Starr                                          12/2/02
----------------------                                       ---------
Signature of Authorized Official                             Date

     /s/Kevin Starr
--------------------------------------
Kevin Starr

CHIEF OPERATING OFFICER
Title

Official and Mailing Address for Notices:

Millennium Pharmaceuticals, Inc.
75 Sidney Street
Cambridge, MA 02139
Attention:  General Counsel

Any false or misleading statements made, presented, or submitted to the
GOVERNMENT, including any relevant omissions, under this AGREEMENT and during
the course of negotiation of this AGREEMENT are subject to all applicable civil
and criminal statutes including Federal statutes 31 U.S.C. 3801-3812 (civil
liability) and 18 U.S.C. 1001 (criminal liability including fine(s) and/or
imprisonment).

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                 APPENDIX A--PATENT(S) OR PATENT APPLICATION(S)

PATENT(S) OR PATENT APPLICATION(S):

I.   U.S. Utility Patent Application U.S.S.N. [**].

II.  U.S. Utility Patent Application U.S.S.N. [**].

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                APPENDIX B--LICENSED FIELDS OF USE AND TERRITORY

LICENSED FIELDS OF USE I: Research, development and manufacture of MLN341 for
distribution, sale and use in oncology disease states within the LICENSED
TERRITORY.

LICENSED FIELDS OF USE II: Research, development and manufacture of dipeptidic
boronic acid compounds and derivatives thereof for distribution, sale and use in
oncology and inflammatory disease states within the LICENSED TERRITORY.

LICENSED TERRITORY: Worldwide

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                              APPENDIX C--ROYALTIES

ROYALTIES:

I.   UP-FRONT ROYALTY:

LICENSEE agrees to pay to PHS a noncreditable, nonrefundable license issue
royalty in the amount of [**] Dollars ($[**]) according to the following payment
schedule:

     a)       [**] Dollars ($[**]) due within thirty (30) days from the
              effective date of this AGREEMENT; and

     b)       [**] Dollars ($[**]) due within three hundred and sixty-five (365)
              days from the effective date of this = AGREEMENT.

II.  MILESTONE ROYALTY:

LICENSEE agrees to pay PHS, within thirty days (30) days of achieving the
benchmark, benchmark royalties as follows:

a)    [**]:                               $[**]
b)   [**]:                                i)       $[**]; or
                                          ii)      $[**]
c)   [**]:                                $[**]
d)   [**]:                                $[**]

For the avoidance of doubt, only one payment will be due in respect of the [**]
and this payment will be either $[**] or $[**], depending on which of the above
criteria is met.

III. RUNNING ROYALTIES:

LICENSEE agrees to pay PHS earned royalties of [**] percent ([**]%) on NET SALES
of Licensed Products by or on behalf of LICENSEE or its sublicenses in the
LICENSED TERRITORY.

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#: A-271-2001]
Model 980611a  Page 24 of 31 (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]

<Page>

In the event that a LICENSED PRODUCT(S) are sold in any country in the form of a
combination product containing one or more therapeutically active ingredients in
addition to such LICENSED PRODUCT(S), NET SALES of such combination product will
be adjusted by multiplying actual NET SALES of such combination product in such
country by the fraction A/(A+B), where A is the average invoice price of the
LICENSED PRODUCT(S) in such country, if sold separately in such country, and B
is the average invoice price of any other therapeutically active ingredients in
the combination in such country, if sold separately in such country. If, in a
specific country, the other therapeutically active ingredients in the
combination product are not sold separately in such country, NET SALES shall be
calculated by multiplying actual NET SALES of such combination product by the
fraction A/C, where A is the average invoice price of the LICENSED PRODUCT(S) in
such country and C is the invoice price of the combination product in such
country. If, in a specific country, the LICENSED PRODUCT(S) are not sold
separately in such country, NET SALES shall be calculated by multiplying actual
NET SALES of such combination product by the fraction C-B/C, where B is the
average invoice price of the other therapeutically active ingredients in the
combination product in such country and C is the invoice price of the
combination product in such country. The invoice price for the LICENSED
PRODUCT(S) and for each other therapeutically active ingredient or process shall
be for a quantity comparable to that used in the combination product and of the
same class, purity and potency. If, in a specific country, both the LICENSED
PRODUCT(S) and the other therapeutically active ingredients in the combination
product are not sold separately in such country, a market price for the LICENSED
PRODUCT(S) and the other therapeutically active ingredients in the combination
product shall be negotiated in good faith by the Parties. In no event shall the
royalty on NET SALES of LICENSED PRODUCT(S) be reduced to less than .25% of NET
SALES of LICENSED PRODUCT(S) as a result of the application of the combination
products provisions of this paragraph.

IV.  SUBLICENSING ROYALTIES:

LICENSEE agrees to pay PHS a sublicensing royalty of [**] percent ([**]%) of (i)
up-front sublicense fees, payments or the equivalent and (ii) milestone payments
attributable to LICENSED PATENT RIGHTS subject to:

            (a)   Payments not exceeding an aggregate lifetime maximum amount of
                  $[**];

            (b)   Subject to (a) above, a minimum payment to PHS of $[**] for
                  each sublicense granted by LICENSEE;

            (c)   This sublicensing royalty shall be computed after excluding
                  the amount of any milestone payments earned and received by
                  LICENSEE from its sublicenses that corresponds to a direct
                  milestone, in Section II of this Appendix C, related royalty
                  paid by LICENSEE to PHS, but shall apply to a) any portion of
                  a milestone payment earned by LICENSEE from a sublicense in
                  excess of these excluded amounts and b) any other milestone
                  payment earned by LICENSEE from a sublicense from a milestone
                  event not provided for under the "Milestone Royalty" as set
                  forth on the prior page of this Appendix C.

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#: A-271-2001]
Model 980611a  Page 25 of 31 (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]

<Page>

For the avoidance of doubt, LICENSEE shall not pay to PHS any proportion of (i)
equity or (ii) future research and development funding.

V.   MINIMUM ANNUAL ROYALTY: [**]

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#: A-271-2001]
Model 980611a  Page 26 of 31 (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]

<Page>

                            APPENDIX D--MODIFICATIONS

PHS and LICENSEE agree to the following modifications to the Articles and
Paragraphs of this AGREEMENT:

All modifications have been incorporated into the body of the AGREEMENT.

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#:  A-271-2001]
Model 980611a  Page 27 of 31  (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]

<Page>

                     APPENDIX E--BENCHMARKS AND PERFORMANCE

LICENSEE agrees to the following BENCHMARKS in LICENSED FIELDS OF USE I for its
performance under this AGREEMENT and, within thirty (30) days of achieving a
BENCHMARK, shall notify PHS that the BENCHMARK has been achieved. If the NDA
filing Benchmark is met prior to reaching the Phase III U.S. Clinical Trial
BENCHMARK, then neither the Phase III U.S. Clinical Trial BENCHMARK nor the
Pre-NDA Meeting with the U.S. Food and Drug Administration BENCHMARK shall be
required. Notwithstanding the above, LICENSEE agrees that if the NDA filing
BENCHMARK results in anything other than an NDA approval, LICENSEE shall notify
PHS pursuant to paragraph 9.02 and this Appendix E shall be modified.

<Table>
<Caption>
BENCHMARK                             ESTIMATED COMPLETION DATE
---------                             -------------------------

<S>                                   <C>
[**]                                  [**]
[**]                                  [**]
[**]                                  [**]
[**]                                  [**]
[**]                                  [**]
</Table>

LICENSED FIELDS OF USE II BENCHMARKS

LICENSEE is currently conducting preclinical evaluation in the area of
dipeptidic boronic acid (or boronate ester) compounds and derivatives in
LICENSED FIELDS OF USE II. Provided the license under Paragraph 3.02 is in
effect, LICENSEE will provide to PHS, on or before [**], a commercial
development plan for research and development of compounds under LICENSED FIELDS
OF USE II.

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#: A-271-2001]
Model 980611a  Page 28 of 31 (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]

<Page>

                     APPENDIX F--COMMERCIAL DEVELOPMENT PLAN

NOTE: THIS DOCUMENT CONTAINS CONFIDENTIAL AND PROPRIETARY TRADE SECRET
INFORMATION OF MILLENNIUM PHARMACEUTICALS, INC. AND IS EXEMPT FROM MANDATORY
DISCLOSURE UNDER THE FREEDOM OF INFORMATION ACT, 5 USC 552 AND ITS IMPLEMENTING
REGULATIONS.

                     COMMERCIAL DEVELOPMENT PLAN FOR MLN341

Background

The licensed patent rights are being used for formulation of MLN341 (also known
as LDP-341 and PS-341), a novel, first in class, highly selective, small
molecule proteasome inhibitor. The proteasome is the multicatalytic enzyme
responsible for protein turnover in eukaryotic cells. Tumor cells are
differentially sensitive compared with normal cells, and blockade of the
proteasome arrests tumor growth by blocking the cell cycle, and inducing
apoptosis.

Millennium Pharmaceuticals, Inc. ("MLNM") is engaged in the development of
MLN341 and is seeking to develop, register and market MLN341 at the earliest
practical date in order to bring lifesaving therapies to cancer patients. MLNM
is utilizing the licensed patent rights under this Agreement to aid in this
effort. As a result of substantial investments to date, MLN341 is in an advanced
stage of development and many commercialization milestones have already been
achieved. A clear indication of MLNM's commitment is that between Q1 2000 and Q1
2002 it invested over $[**] in direct research and development expenses for
preclinical and clinical studies, and in 2002 alone it is estimated that direct
research and development costs, largely driven by the costs of advanced stage
clinical trials, will exceed $[**]. This level of investment demonstrates MLNM's
commitment to completing the commercialization of MLN341.

Evaluation of MLNM in [**]

The primary indication for which MLN341 is being developed is [**], an
indication for which there is clear and present medical need. Millennium expects
to announce the initiation of a Phase III clinical trial for patients [**]. MLNM
has already achieved, and plans to achieve, the clinical and regulatory
milestones set forth below.

<Table>
<Caption>
MLN34I CLINICAL AND REGULATORY            COMPLETION DATE OR ESTIMATED
----------------------------------------------------------------------
<S>                                       <C>
[**]                                      [**]
[**]                                      [**]
[**]                                      [**]
[**]                                      [**]
[**]                                      [**]
[**]                                      [**]
[**]                                      [**]
</Table>

*Note: Because of the unmet medical need for effective therapies for [**], MLNM
is not satisfied with the customary development timeline applicable to products
subject to the normal

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#: A-271-2001]
Model 980611a  Page 29 of 31 (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]

<Page>

approval route before the United States Food and Drug Administration ("FDA").
Accordingly, while MLNM is planning to conduct clinical trials based on
traditional development timelines, MLNM is also in discussions with the FDA
regarding the potential for accelerated approval of MLN341 based on current
Phase 11 data. It would not be appropriate for MLNM to make any public
disclosure of these discussions [**]. However, should the FDA concur with MLNM's
perspective on the promising response rates in this patient population,
accelerated approval for MLN341 [**] could accelerate approval and launch of MLN
341 in this indication by up to [**]. While the outcome of this effort is
dependent on the data and agreement with FDA, it is further evidence of the
substantial effort MLNM is making to expeditiously develop and register the
product.

Development of MLNM for Additional Indications

[**]is only the beginning, and while a very significant step on its own, MLNM is
also evaluating MLN341 for the following additional indications, many of which
are the subject of active clinical trials:

    -    [**];

    -    [**];

    -    [**];

    -    [**];

    -    [**]; and

    -    [**].

Depending on the sufficiency of data obtained in Phase II and Phase III trials
and their acceptability to the FDA, it is anticipated that MLN341 could reach
the market for one or more of these secondary indications in [**]. MLNM may also
engage in collaborative development and commercialization activities with third
parties that have products, technology or capability that will enhance the value
of MLN341.

Caveats

It must be emphasized that the above timelines are estimates only, based on
currently available information and good faith estimates by MLNM personnel, and
cannot be taken to predict the outcome of further development of MLN341.
Millennium cannot be certain that any product will ultimately prove to be safe
or effective, will receive regulatory approvals, or will be successfully
commercialized.

Commercialization Activities

MLNM's marketing and sales organization has an ongoing market research program
to identify the required MLN341 clinical profile and market dynamics in each
clinical indication, and is

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#: A-271-2001]
Model 980611a  Page 30 of 31 (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]

<Page>

shaping its product profiles according to this data and direct input from
clinical investigators and thought leaders in Oncology practice.

Communication with clinicians on the clinical benefits of MLN341 and feedback on
clinical trial design is the responsibility of the MLNM product team. MLNM is
actively engaged in educational activities as it prepares for the registration
and launch of MLN341. MLNM is an active participant in key scientific meetings
such as the American Society of Clinical Oncology and the American Society of
Hematology, where it has published numerous findings from its preclinical and
clinical research. MLN341 has been and will be the subject of publications in
peer-reviewed medical journals based on the data from the clinical program. MLNM
has created an advisory board of clinical experts for MLN341 and is in active
dialog with key advocacy groups.

MLNM's oncology marketing organization is actively planning MLN341 sales and
marketing activities consistent with the advanced stage of development of the
product, including product labeling, package inserts, pricing, reimbursement,
and product branding with MD's and other health practitioners.

To date, MLNM has retained commercial rights to market MLN341 directly, and is
expanding its medical affairs, marketing and sales groups consistent with an
aggressive timeline for product launch in multiple indications. In the event
that MLNM elects to collaborate with a third party with synergistic products,
technology or capability that will enhance the value of MLN341, MLNM may offer
commercialization rights to the collaborator as part of the transaction.

Commercial scale manufacturing contracts are in place for producing the initial
cGMP commercial scale manufacturing runs. Based on the data from these initial
runs, longer term commercial supply contracts will be negotiated with key
suppliers for MLN341. Accordingly, MLNM is now well-positioned to manufacture
and supply MLN341 for the initial launch. MLNM is also engaged in the sourcing
of second suppliers to ensure adequate capacity for all market conditions and
guard against potential supply chain interruptions.

LICENSED FIELDS OF USE II

Licensee is currently conducting preclinical evaluation in the area of [**].
Provided the license under S. 3.02 is in effect, Licensee will provide to PHS,
on or before [**], a Commercial Development Plan for research and development of
compounds under Licensed Fields of Use II.

Summary

The MLN341 commercialization program is designed to ensure that this exciting
compound is developed, registered, launched and marketed with a level of
diligence that equals or exceeds that normally in place at the time a customary
patent license is entered into by the NCI, and the significant investment made
to date demonstrates MLNM's strong commitment and motivation to completing this
effort with all deliberate speed.

PHS Patent License Agreement--EXCLUSIVE CONFIDENTIAL (A#: A-271-2001]
Model 980611a Page 31 of 31 (Final) (Millennium Pharmaceuticals, Inc.)
[November 12, 2002]<Page>
                                                                   Exhibit 10.21

As amended through April 30, 2003 and adjusted for stock splits in April and
October 2000

                        MILLENNIUM PHARMACEUTICALS, INC.

                        1996 EMPLOYEE STOCK PURCHASE PLAN

     The purpose of this Plan is to provide eligible employees of Millennium
Pharmaceuticals, Inc. (the "Company") and certain of its subsidiaries with
opportunities to purchase shares of the Company's Common Stock (the "Common
Stock"). Five Million Six Hundred Thousand (5,600,000) shares of Common Stock in
the aggregate have been approved for this purpose.

     1. ADMINISTRATION. The Plan will be administered by the Company's Board of
Directors (the "Board") or by a Committee appointed by the Board (the
"Committee"). The Board or the Committee has authority to make rules and
regulations for the administration of the Plan and its interpretation and
decisions with regard thereto shall be final and conclusive.

     2. ELIGIBILITY. Participation in the Plan will neither be permitted nor
denied contrary to the requirements of Section 423 of the Internal Revenue Code
of 1986, as amended (the "Code"), and regulations promulgated thereunder. All
individuals designated, classified or otherwise considered by the Company, or by
any subsidiary of the Company (as defined in Section 424(f) of the Code)
designated by the Board or the Committee from time to time (a "Designated
Subsidiary"), to be employees, including directors who are employees, are
eligible to participate in any one or more of the offerings of Options (as
defined below) to purchase Common Stock under the Plan, provided that:

          (a) they are regularly employed by the Company or a Designated
     Subsidiary for more than 20 hours a week and for more than five months in a
     calendar year; and

          (b) they are employees of the Company or a Designated Subsidiary on
     the first day o f the applicable Plan Period (as defined below)."

     No employee may be granted an option hereunder if such employee,
immediately after the option is granted, owns 5% or more of the total combined
voting power or value of the stock of the Company or any subsidiary. For
purposes of the preceding sentence, the attribution rules of Section 424(d) of
the Code shall apply in determining the stock ownership of an employee, and all
stock which the employee has a contractual right to purchase shall be treated as
stock owned by the employee.
<Page>

     3. OFFERINGS. The Company will make one or more offerings ("Offerings") to
employees to purchase Common Stock under this Plan. The Board or the Committee
shall determine the commencement dates of each of the Offerings (the "Offering
Commencement Dates"). Each Offering Commencement Date will begin a period (a
"Plan Period") during which payroll deductions will be made and held for the
purchase of Common Stock at the end of the Plan Period. The Board or the
Committee shall choose a Plan Period of twelve (12) months or less for each of
the Offerings and may, at its discretion, choose a different Plan Period for
each Offering.

     4. PARTICIPATION. An employee eligible on the Offering Commencement Date of
any Offering may participate in such Offering by completing and forwarding a
payroll deduction authorization form to the Controller of the Company at least
14 days prior to the applicable Offering Commencement Date. The form will
authorize a regular payroll deduction from the Compensation received by the
employee during the Plan Period. Unless an employee files a new form or
withdraws from the Plan, his deductions and purchases will continue at the same
rate for future Offerings under the Plan as long as the Plan remains in effect.
The term "Compensation" means the amount of money reportable on the employee's
Federal Income Tax Withholding Statement, excluding overtime, shift premium,
incentive or bonus awards, allowances and reimbursements for expenses such as
relocation allowances for travel expenses, income or gains on the exercise of
Company stock options or stock appreciation rights, and similar items, whether
or not shown on the employee's Federal Income Tax Withholding Statement, but
including, in the case of salespersons, sales commissions to the extent
determined by the Board or the Committee.

     5. DEDUCTIONS.

          (a) The Company will maintain payroll deduction accounts for all
participating employees. With respect to any Offering made under this Plan, an
employee may authorize a payroll deduction in any dollar amount up to a maximum
of 10% of the Compensation he or she receives during the Plan Period or such
shorter period during which deductions from payroll are made. Payroll deductions
may be at the rate of 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10% of Compensation.

          (b) No employee may be granted an Option which permits his rights to
purchase Common Stock under this Plan and any other stock purchase plan of the
Company and its subsidiaries, to accrue at a rate which exceeds $25,000 of the
fair market value of such Common Stock (determined at the Offering Commencement
Date of the Plan Period) for each calendar year in which the Option is
outstanding at any time.

                                       2
<Page>

     6. DEDUCTION CHANGES. An employee may decrease or discontinue his payroll
deduction once during any Plan Period by filing a new payroll deduction
authorization form. However, an employee may not increase his payroll deduction
during a Plan Period. If an employee elects to discontinue his payroll
deductions during a Plan Period, but does not elect to withdraw his funds
pursuant to Section 8 hereof, funds deducted prior to his election to
discontinue will be applied to the purchase of Common Stock on the Exercise Date
(as defined below).

     7. INTEREST. Interest will not be paid on any employee payroll deduction
accounts, except to the extent that the Board or its Committee, in its sole
discretion, elects to credit such accounts with interest at such per annum rate
as it may from time to time determine.

     8. WITHDRAWAL OF FUNDS. An employee may on any one occasion during a Plan
Period and for any reason withdraw all or part of the balance accumulated in the
employee's payroll deduction account. Any such withdrawal must be effected prior
to the close of business on the last day of the Plan Period. If the employee
withdraws all of such balance, the employee shall thereby withdraw from
participation in the Offering and may not begin participation again during the
remainder of the Plan Period. Any employee withdrawing all or part of such
balance may participate in any subsequent Offering in accordance with terms and
conditions established by the Board or the Committee, except that, unless
otherwise permitted under Section 16 of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), and the rules promulgated thereunder, any employee
who is also a director and/or officer of the Company within the meaning of
Section 16 of the Exchange Act may not (a) withdraw less than all of the balance
accumulated in such employee's payroll deduction account or (b) participate
again for a period of at least six months as provided in Rule l6b-3(d)(2)(i) or
any successor provision under the Exchange Act.

     9. PURCHASE OF SHARES.

          (a) On the Offering Commencement Date of each Plan Period, the Company
will grant to each eligible employee who is then a participant in the Plan an
option (an "Option") to purchase on the last business day of such Plan Period
(the "Exercise Date"), at the Option Price hereinafter provided for, such number
of whole shares of Common Stock of the Company reserved for the purposes of the
Plan as does not exceed the number of shares determined by dividing 15% of such
employee's annualized Compensation for the immediately prior six-month period by
the price determined in accordance with the formula set forth in the following
paragraph but using the closing price on the Offering Commencement Date of such
Plan Period.

          (b) The Option Price for each share purchased will be 85% of the
closing price of the Common Stock on (i) the first

                                       3
<Page>

business day of such Plan Period or (ii) the Exercise Date, whichever closing
price shall be less. Such closing price shall be (A) the closing price of the
Common Stock on any national securities exchange on which the Common Stock is
listed, or (B) the closing price of the Common Stock on the Nasdaq National
Market ("Nasdaq") or (C) the average of the closing bid and asked prices in the
over-the-counter market, whichever is applicable, as published in THE WALL
STREET JOURNAL. If no sales of Common Stock were made on such a day, the price
of the Common Stock for purposes of clauses (A) and (B) above shall be the
reported price for the next preceding day on which sales were made.

          (c) Each employee who continues to be a participant in the Plan on the
Exercise Date shall be deemed to have exercised his Option at the Option Price
on such date and shall be deemed to have purchased from the Company the number
of full shares of Common Stock reserved for the purpose of the Plan that his
accumulated payroll deductions on such date will pay for pursuant to the formula
set forth above (but not in excess of the maximum number determined in the
manner set forth above).

          (d) Any balance remaining in an employee's payroll deduction account
at the end of a Plan Period will be automatically refunded to the employee,
except that any balance which is less than the purchase price of one share of
Common Stock will be carried forward into the employee's payroll deduction
account for the following Offering, unless the employee elects not to
participate in the following Offering under the Plan, in which case the balance
in the employee's account shall be refunded.

     10. ISSUANCE OF CERTIFICATES. Certificates representing shares of Common
Stock purchased under the Plan may be issued only in the name of the employee,
in the name of the employee and another person of legal age as joint tenants
with rights of survivorship, or (in the Company's sole discretion) in the street
name of a brokerage firm, bank or other nominee holder designated by the
employee.

     11. RIGHTS ON RETIREMENT, DEATH OR TERMINATION OF EMPLOYMENT. In the event
of a participating employee's termination of employment prior to the last
business day of a Plan Period (whether as a result of the employee's voluntary
or involuntary termination, retirement, death or otherwise), no payroll
deduction shall be taken from any pay due and owing to the employee and the
balance in the employee's payroll deduction account shall be paid to the
employee or, in the event of the employee's death, (a) to a beneficiary
previously designated in a revocable notice signed by the employee (with any
spousal consent required under state law) or (b) in the absence of such a
designated beneficiary, to the executor or administrator of the employee's
estate or (c) if no such executor or administrator has been appointed to the
knowledge of the Company, to such other person(s) as the Company may, in its
discretion, designate. If,

                                       4
<Page>

prior to the last business day of the Plan Period, the Designated Subsidiary by
which an employee is employed shall cease to be a subsidiary of the Company, or
if the employee is transferred to a subsidiary of the Company that is not a
Designated Subsidiary, the employee shall be deemed to have terminated
employment for the purposes of this Plan.

     12. OPTIONEES NOT STOCKHOLDERS. Neither the granting of an Option to an
employee nor the deductions from his pay shall constitute such employee a
stockholder of the shares of Common Stock covered by an Option under this Plan
until such shares have been purchased by and issued to him.

     13. RIGHTS NOT TRANSFERABLE. Rights under this Plan are not transferable by
a participating employee other than by will or the laws of descent and
distribution, and are exercisable during the employee's lifetime only by the
employee.

     14. APPLICATION OF FUNDS. All funds received or held by the Company under
this Plan may be combined with other corporate funds and may be used for any
corporate purpose.

     15. ADJUSTMENT IN CASE OF CHANGES AFFECTING COMMON STOCK. In the event of a
subdivision of outstanding shares of Common Stock, or the payment of a dividend
in Common Stock, the number of shares approved for this Plan, and the share
limitation set forth in Section 9, shall be increased proportionately, and such
other adjustment shall be made as may be deemed equitable by the Board or the
Committee. In the event of any other change affecting the Common Stock, such
adjustment shall be made as may be deemed equitable by the Board or the
Committee to give proper effect to such event.

     16. MERGER.

          (a) If the Company shall at any time merge or consolidate with another
corporation and the holders of the capital stock of the Company immediately
prior to such merger or consolidation continue to hold at least 80% by voting
power of the capital stock of the surviving corporation ("Continuity of
Control"), the holder of each Option then outstanding will thereafter be
entitled to receive at the next Exercise Date upon the exercise of such Option
for each share as to which such Option shall be exercised the securities or
property which a holder of one share of the Common Stock was entitled to upon
and at the time of such merger, and the Board or the Committee shall take such
steps in connection with such merger as the Board or the Committee shall deem
necessary to assure that the provisions of Section 15 shall thereafter be
applicable, as nearly as reasonably may be, in relation to the said securities
or property as to which such holder of such Option might thereafter be entitled
to receive thereunder.

                                       5
<Page>

          (b) In the event of a merger or consolidation of the Company with or
into another corporation which does not involve Continuity of Control, or of a
sale of all or substantially all of the assets of the Company while unexercised
Options remain outstanding under the Plan, (i) subject to the provisions of
clauses (ii) and (iii), after the effective date of such transaction, each
holder of an outstanding Option shall be entitled, upon exercise of such Option,
to receive in lieu of shares of Common Stock, shares of such stock or other
securities as the holders of shares of Common Stock received pursuant to the
terms of such transaction; or (ii) all outstanding Options may be cancelled by
the Board or the Committee as of a date prior to the effective date of any such
transaction and all payroll deductions shall be paid out to the participating
employees; or (iii) all outstanding Options may be cancelled by the Board or the
Committee as of the effective date of any such transaction, provided that notice
of such cancellation shall be given to each holder of an Option, and each holder
of an Option shall have the right to exercise such Option in full based on
payroll deductions then credited to his account as of a date determined by the
Board or the Committee, which date shall not be less than ten (10) days
preceding the effective date of such transaction.

     17. AMENDMENT OF THE PLAN. The Board may at any time, and from time to
time, amend this Plan in any respect, except that (a) if the approval of any
such amendment by the stockholders of the Company is required by Section 423 of
the Code or by Rule 16b-3 under the Exchange Act, such amendment shall not be
effected without such approval, and (b) in no event may any amendment be made
which would cause the Plan to fail to comply with Section 16 of the Exchange Act
and the rules promulgated thereunder, as in effect from time to time, or Section
423 of the Code.

     18. INSUFFICIENT SHARES. In the event that the total number of shares of
Common Stock specified in elections to be purchased under any Offering plus the
number of shares purchased under previous Offerings under this Plan exceeds the
maximum number of shares issuable under this Plan, the Board or the Committee
will allot the shares then available on a pro rata basis.

     19. TERMINATION OF THE PLAN. This Plan may be terminated at any time by the
Board. Upon termination of this Plan all amounts in the payroll deduction
accounts of participating employees shall be promptly refunded.

     20. GOVERNMENTAL REGULATIONS.

          (a) The Company's obligation to sell and deliver Common Stock under
this Plan is subject to listing on a national stock exchange or quotation on
Nasdaq and the approval of all governmental authorities required in connection
with the authorization, issuance or sale of such stock.

                                       6
<Page>

          (b) The Plan shall be governed by the laws of the State of Delaware
except to the extent that such law is preempted by federal law.

          (c) The Plan is intended to comply with the provisions of Rule 16b-3
promulgated under the Exchange Act. Any provision inconsistent with such Rule
shall to that extent be inoperative and shall not affect the validity of the
Plan.

     21. ISSUANCE OF SHARES. Shares may be issued upon exercise of an Option
from authorized but unissued Common Stock, from shares held in the treasury of
the Company, or from any other proper source.

     22. NOTIFICATION UPON SALE OF SHARES. Each employee agrees, by entering the
Plan, to promptly give the Company notice of any disposition of shares purchased
under the Plan where such disposition occurs within two years after the date of
grant of the Option pursuant to which such shares were purchased.

     23. EFFECTIVE DATE AND APPROVAL OF STOCKHOLDERS. The Plan shall take effect
upon the closing of the Company's initial public offering of Common Stock
pursuant to an effective registration statement under the Securities Act of
1933, as amended, subject to approval by the stockholders of the Company as
required by Rule 16b-3 under the Exchange Act and by Section 423 of the Code,
which approval must occur within twelve months of the adoption of the Plan by
the Board.

                                       7

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