EXHIBIT 10.53 AMENDMENT NO. 1 TO ENBREL SUPPLY AGREEMENT

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                                                           EXHIBIT 10.53

* CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY THE

BRACKETS, HAS BEEN OMITTED AND FILED WITH THE SECURITIES AND EXCHANGE COMMISSION

PURSUANT TO RULE 24b-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

                   AMENDMENT NO. 1 TO ENBREL SUPPLY AGREEMENT

         This AMENDMENT NO. 1 TO ENBREL SUPPLY AGREEMENT (this "Amendment") is

entered into effective as of the 20th day of September 2002 by and between

Genentech Inc., a Delaware corporation ("Genentech") and Immunex Corporation, a

Washington corporation and a wholly-owned subsidiary of Amgen Inc. ("Immunex"),

and amends that certain Enbrel Supply Agreement entered into by Genentech and

Immunex on April 12, 2002 (the "Agreement").

         For good and valuable consideration, the receipt and sufficiency of

which are hereby acknowledged, Genentech and Immunex (the "Parties") agree as

follows:

1.        Section 5.2(b) of the Agreement is amended to read in its entirety as

         follows:

         "5