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                                                                  EXHIBIT 10.8


          Confidential Materials omitted and filed separately with the
         Securities and Exchange Commission. Asterisks denote omissions.


                                               June 4, 2002

Re:  ADVANCE MI Study

Gentlemen:

         As you are aware, Schering Corporation ("Schering") and Millennium
Pharmaceuticals, Inc. ("Millennium") are considering undertaking a Study (as
defined below) under the terms of the Collaboration Agreement, dated April 10,
1995, as amended (the "Agreement").

         This letter confirms that Schering has agreed in principle to pay the
lesser of (i) $[**] or (ii) [**] percent ([**]%) of the cost of the ADVANCE MI
clinical study that has been proposed by Millennium to the FDA at the meeting on
May 22, 2002 (the protocol for which is attached to this letter and made a part
hereof). Following the FDA meeting, Schering and Millennium will promptly meet
to review all FDA requested changes. Schering and Millennium will in good faith
discuss and seek agreement to include such changes to the study as may be
necessary from a clinical safety standpoint or as otherwise agreed. Both Parties
will use good faith efforts to have the ADVANCE-MI protocol finalized and issued
(the "Study") no more than ten (10) business days after the FDA meeting.

         Agreement by Schering under this letter agreement to fund the Study is
         made on the condition that if the following three events (i-iii) occur:

         (i) [**] (as defined in the Study protocol) for the study [**] for the
         study [**] and;

         (ii) the [**] for the [**] more than the [**] in the [**] and;

         (iii) the [**] for the [**] more than the [**] and;

         AND if either or both of the following two events (iv and v) occur:

         (iv) [**] Millennium/Schering [**] to the [**]; or

         (v)  [**] the final results of the Study, [**]
              [**] that is [**]l; or, (2) [**] that is [**]

then Millennium shall reimburse Schering for the payments incurred by Schering
for the Study.

         If the expenditures for the Study are projected to exceed $[**], then
Millennium will have the sole authority to accept or reject the additional
expenditures and will bear sole financial responsibility for the additional
expenditures.

         The reimbursement, if any, will be made [**] the completed results of
the Study (e.g., first publication of an abstract or paper based on the
completed results). However,


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if [**] based upon the [**] study, reimbursement, if any, will be made [**],
subject to reasonable efforts and reasonable timing [**] as defined above. The
reimbursement, if any, will be paid [**].

         It is acknowledged and agreed that the Study will be conducted under
the terms of the Agreement; provided that notwithstanding any terms or
conditions of the Agreement to the contrary, the parties' financial obligations
with respect to the cost of the Study shall be governed by the terms of this
letter agreement. Except as expressly modified by the terms of this letter
agreement, all of the terms and conditions of the Agreement shall remain in full
force and effect.

                                      Millennium Pharmaceuticals, Inc.

                                      By: /s/ ARTHUR J. HILLER
                                          --------------------

                                      Name:  ARTHUR J. HILLER
                                             ----------------

                                      Title:  GENERAL MANAGER,
                                              ---------------
                                              CARDIOVASCULAR

Agreed and Accepted:

Schering Corporation

By:  /s/ DAVID POORVIN
     -----------------

Name:  DAVID POORVIN
       -------------

Title:  VICE PRESIDENT
        --------------