COR THERAPEUTICS INC / DE
EXHIBIT 10.2
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<TYPE>EX-10.2
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<FILENAME>f66355ex10-2.txt
<DESCRIPTION>EXHIBIT 10.2
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                                                                    EXHIBIT 10.2

                  [SCHERING-PLOUGH PHARMACEUTICALS LETTERHEAD]


                                                        August 31, 2000


Mr. Vaughn M. Kailian, CEO
COR Therapeutics, Inc.
256 East Grand Avenue
South San Francisco, California 94080

Dear Vaughn:

This is with regard to the Collaboration Agreement, dated April 10, 1995, by
and among COR Therapeutics, Inc. ("COR"), and Schering Corporation and Schering-
Pough Ltd. (collectively "Schering"), as amended, (the "Agreement").

In the Second Amendment to the Agreement, dated November 5, 1999, COR and
Schering agreed to make certain elements of the Second Amendment conditional on
the conduct of a Phase III clinical trial for acute myocardial infarction
("AMI") and have made provision in the Second Amendment for modification of the
Second Amendment based upon the status of such trial as of pre-established
dates, and the parties desire to modify those dates.

The parties are currently negotiating a Third Amendment to the Agreement to
address this and other issues relating to the Agreement. However, Section X.A
of the Second Amendment provides for the termination of certain provisions of
the Second Amendment in the event that "as of June 30, 2000, the JSC has not
voted to conduct the Phase III Study". Therefore, it is hereby agreed that the
deadline for the decision of the JSC with respect to the conduct of the Phase
III Study is extended until September 8, 2000.

Please indicate COR's acceptance and agreement to the provisions set forth in
this letter by signing below on behalf of COR and returning one signed original
to Schering.

Very truly yours,

Schering Corporation                         Schering-Plough Ltd.

/s/ THOMAS C. LAUDA                          /s/ DAVID POORVIN
-------------------------------              ---------------------------------
Thomas C. Lauda                              David Poorvin
Executive Vice President                     Prokurist
Schering-Plough Pharmaceuticals


Acknowledged and Agreed to:

COR Therapeutics, Inc.

By: /s/ VAUGHN M. KAILIAN
    ---------------------------
    Vaughn M. Kailian
    Chief Executive Officer

Date:         09/05/00
      -------------------------

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