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                                                                   EXHIBIT 10.33



                                              November 7, 2003


Charles J. Homcy
c/o Portola Pharmaceuticals, Inc.
270 East Grand Avenue
South San Francisco, CA  94080

Dear Mr. Homcy:

         Reference is made to the letter agreement between us dated December 24,
2002 (the "December Letter"). This letter memorializes certain verbal agreements
between you and Millennium Pharmaceuticals, Inc. ("Millennium") that we are
making upon the termination of your employment with Millennium effective as of
November 7, 2003 (the "Termination Date").

         1. As described in the December Letter, you are now entitled to certain
benefits upon the termination of your employment. We will provide you with the
benefits described in Section 4(a) (Base Salary) based on your salary at the
time of the Millennium's merger (the "Merger") with COR Therapeutics, Inc.
("COR") of $381,600, 4(b) (Bonus) based on your bonus target at the time of the
Merger of 50% and 4(c) (Health Benefits) of the COR Key Employee Severance Plan
(the "Plan"). Millennium will make salary continuation payments in regular
installments on the normal payroll dates of Millennium, or over a shorter period
as determined by Millennium. Millennium will pay you the pro rata bonus benefit
based on the actual funding for the year 2003 as determined by Millennium's
Board of Directors, with such payment being made at the same time as payments
for other executives of Millennium. Any such amounts that you receive will be
subject to all required tax withholding.

         2. Because the Termination Date is prior to February 12, 2004, any
outstanding options to purchase shares of the common stock of Millennium
("Pre-Merger Options") held by you on February 12, 2002 (immediately after the
Merger) immediately vested and became exercisable in full as of the Termination
Date. All such Pre-Merger Options will otherwise remain subject to the terms and
conditions set forth in the applicable stock option plans and stock option
agreements.

         3. You expect to remain in your role as a Director of Millennium. Under
Millennium's 2000 Stock Incentive Plan (the "2000 Plan") you are eligible to
continue vesting into any options you have received under that plan
("Post-Merger Options") so long as you serve as a Millennium Director. You have,
however, agreed that all of the

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Post-Merger Options that you held as of the Termination Date will cease vesting
on the earlier to occur of: a) the end of your service as a Millennium Director
or b) one year from the Termination Date. The Post-Merger Options will remain
subject to the terms and conditions set forth in the 2000 Plan and stock option
agreements. Any options you receive after the date hereof will vest and be
exercisable in accordance with their terms. You will not receive the normal
stock option grants for new outside directors of Millennium, but will be
eligible for stock option grants as continuing directors on the same basis as
other continuing directors, with the first such grant to be pro-rated based on
the Termination Date.

         4. If any payment or benefit you would receive pursuant to this
agreement, when combined with any other payment or benefit you receive pursuant
to the termination of your employment with Millennium ("Payment") would (i)
constitute a "parachute payment" within the meaning of Section 280G of the
Internal Revenue Code of 1986, as amended (the "Code"), and (ii) but for this
sentence, be subject to the excise tax imposed by Section 4999 of the Code (the
"Excise Tax"), then such Payment will be either (x) the full amount of Payment
or (y) such lesser amount (with cash payments being reduced before stock option
compensation) as would result in no portion of the Payment being subject to the
Excise Tax, whichever of the foregoing amounts, taking into account the
applicable federal, state and local employment taxes, income taxes, and the
Excise Tax results in your receipt, on an after-tax basis, of the greater amount
of the Payment notwithstanding that all or some portion of the Payment may be
subject to the Excise Tax.

         5. In consideration of receiving the consideration outlined herein, you
hereby release and forever discharge and hold Millennium, as well as its current
and former successors, employees, officers, directors, shareholders, parents,
subsidiaries, affiliates and agents, harmless of all claims or suits of any
nature whatsoever, including, but not limited to, any claims under federal,
state and local laws that prohibit discrimination (including without limitation,
claims of discrimination based on race, age, religion, national origin, sex,
disability or handicap, and sexual orientation) and any claims with respect to
breach of contract (express and/or implied), wrongful termination, Worker
Adjustment and Retraining Notification Act and related state statute
notification obligations, the Older Workers Benefit Protection Act of 1990 and
related state statutes, intentional or negligent infliction of emotional
distress, interference with contractual or advantageous business relations, loss
of consortium, invasion of privacy, defamation, payment of wages, debts, costs
and expenses, attorneys' fees and other damages, and any claims arising out of
or in any way related to your employment with Millennium, which you now have,
may have, or may have had from the beginning of time to the Termination Date.
Nothing in this paragraph shall be construed in any way to release Millennium
from its obligation to indemnify you from any third party action brought against
you based on your employment with or service as a Director to Millennium
pursuant to any applicable agreement or applicable law or to reduce or eliminate
any coverage you may have under Millennium's director and officer liability
policy, if any.

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         6. As required by the Older Workers Benefit Protection Act of 1990, you
acknowledge: (i) that you have been advised and given the opportunity to consult
with your own counsel prior to signing this letter agreement; (ii) that you have
been given up to 45 days from the receipt of this letter agreement to consider
whether to sign it; (iii) that you have been advised that even after you sign
this letter agreement, you may revoke it within 7 days of the date of your
signing, by delivering a signed revocation notice to Millennium's Vice-President
of Human Resources; (iv) that this letter agreement shall not become effective
and in force until eight (8) days after you sign it, and (v) that you will not
be entitled to receive the payments described herein until after the 7-day
revocation period has expired, and that, should you in fact revoke your
acceptance, none of the payments outlined in Paragraph 1 will be made.

         7. This agreement may be amended or modified only by a written
instrument executed by you and Millennium. This agreement will be interpreted
and enforced in accordance with the laws of the Commonwealth of Massachusetts.

         Please acknowledge your agreement by countersigning this letter below.

                                Sincerely,

                                MILLENNIUM PHARMACEUTICALS, INC.

                                By: /s/ KENNETH BATE
                                Name:  Kenneth Bate
                                Title: EVP and Chief Financial Officer


AGREED TO:


/s/ CHARLES J. HOMCY
Charles J. Homcy