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                                                           EXHIBIT 10.63



                   AMENDMENT NO. 2 TO ENBREL SUPPLY AGREEMENT

         THIS AMENDMENT NO. 2 TO ENBREL SUPPLY AGREEMENT (this "Amendment") is
entered into effective as of the 16th day of July, 2002, between and among
Genentech Inc., a Delaware corporation ("Genentech"), Immunex Corporation, a
Washington corporation and a wholly-owned subsidiary of Amgen Inc. ("Immunex"),
and Amgen Inc., a Delaware corporation ("Amgen").

         Genentech and Immunex are parties to that certain ENBREL Supply
Agreement dated April 12, 2002, as amended by that certain Amendment No. 1 to
ENBREL Supply Agreement dated September 20, 2002 (as amended, the "Agreement").
On July 16, 2002, Amgen acquired Immunex, making Immunex a wholly-owned
subsidiary of Amgen, and Genentech, Immunex and Amgen (collectively, the
"Parties") wish to amend the Agreement accordingly.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Parties agree as follows:

1.       Amendments to Defined Terms.

         1.1      Section 1.33 (Genentech Confidential Information). Section
                  1.33 (Genentech Confidential Information) of the Agreement is
                  amended to read in its entirety as follows:

                  "1.33 Genentech Confidential Information" means all technical
                  and other information, whether patented or unpatented,
                  relating to the Genentech Facility, and/or Genentech
                  processes, methods, operations, technologies, forecasts and
                  business information that are disclosed or supplied to, or
                  used on behalf of, Immunex or its Affiliates (including
                  without limitation Amgen Inc.) by Genentech pursuant to, or by
                  any of Genentech's agents or contractors pursuant to, this
                  Agreement, the Tech Transfer Agreement and/or the Quality
                  Agreement, or of which Immunex or its Affiliates (including
                  without limitation Amgen Inc.) may become aware of through the
                  presence of their employees or agents at Genentech offices or
                  at the Genentech Facility, including, without limitation,
                  trade secrets, know-how, processes, concepts, experimental
                  methods and results and business and scientific plans and
                  information and facility layout and schematics."

         1.2      Section 1.38 (Immunex Confidential Information). Section 1.38
                  (Immunex Confidential Information) of the Agreement is amended
                  to read in its entirety as follows:

                  "1.38 Immunex Confidential Information" means the Cell Line,
                  Master Cell Bank, Working Cell Bank, Manufacturing
                  Documentation, Manufacturing Process, and Product, and all
                  technical and other information, whether patented or
                  unpatented, relating thereto and/or to Immunex's or any of its
                  Affiliates' (including without limitation Amgen Inc.)
                  processes, methods, operations, technologies, forecasts and
                  business information that are disclosed or supplied to
                  Genentech by or on behalf of Immunex or its Affiliates
                  (including without limitation Amgen Inc.) pursuant to this
                  Agreement, the Tech Transfer Agreement and/or the Quality
                  Agreement, or of which Genentech may become aware of through
                  the presence of its employees or agents at Immunex offices or
                  facilities or at

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                  offices or facilities of Immunex Affiliates (including without
                  limitation Amgen Inc.) or at other facilities that manufacture
                  the Product, including, without limitation, trade secrets,
                  know-how, processes, concepts, experimental methods and
                  results and business and scientific plans and information and
                  facility layout and schematics. All portions of documents and
                  records describing or to the extent relating to the
                  Manufacturing Process at the Genentech Facility, including,
                  without limitation, process trend and variability data related
                  to the Product, shall be deemed to be Immunex Confidential
                  Information."

2.       Confidentiality Obligations.

         2.1      Amendments to Article 17, Confidentiality. Article 17 of the
                  Agreement, Confidentiality, is amended as follows:

                  A. Section 17.1 (a) (Genentech Confidentiality Obligations).
                  Section 17.1(a)(2) is amended to read in its entirety as
                  follows: "(2) contractors who are bound by similar obligations
                  of confidentiality and nonuse and who have a need to know such
                  information in order to provide direction to Genentech or
                  Immunex or Immunex's Affiliates (including without limitation
                  Amgen Inc.) regarding the respective obligations of Genentech,
                  Immunex and Immunex's Affiliates (including without limitation
                  Amgen, Inc.), under this Agreement, the Tech Transfer
                  Agreement and/or the Quality Agreement, or."

                  B. Section 17.1(b) (Immunex Confidentiality Obligations).
                  Section 17.1(b)(1) is amended to read in its entirety as
                  follows: "(1) employees, consultants, agents or contractors of
                  Immunex or Immunex's Affiliates (including without limitation
                  Amgen Inc.) who are bound by similar obligations of
                  confidentiality and nonuse and who have a need to know such
                  information in order to perform their duties in carrying out
                  Immunex's obligations under this Agreement, the Tech Transfer
                  Agreement and/or the Quality Agreement, or in order to provide
                  direction to Immunex regarding production, testing, storage or
                  quality of the Product or regulatory or compliance issues
                  related to the Product, or."

         2.2      Genentech Reaffirmation of Confidentiality Obligations.
                  Genentech hereby restates and reaffirms, for the benefit of
                  Immunex and Amgen, (i) Genentech's confidentiality obligations
                  under Article 17 of the Agreement (as amended by this
                  Amendment), including without limitation the obligations
                  contained in Section 17.1(a), and (ii) Genentech's
                  confidentiality obligations under the Tech Transfer Agreement;
                  and the Parties agree that Amgen is an intended third party
                  beneficiary of all such obligations of confidentiality, to the
                  same extent and with the same effect as if Amgen were the
                  party named therein, and Amgen shall have the right to enforce
                  such obligations of confidentiality against Genentech as if
                  Amgen were a party to the Agreement and the Tech Transfer
                  Agreement.

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         2.3      Immunex Reaffirmation of Confidentiality Obligations. Immunex
                  hereby restates and reaffirms (i) Immunex's confidentiality
                  obligations under Article 17 of the Agreement (as amended by
                  this Amendment), including without limitation the obligations
                  contained in Section 17.1(b), and (ii) Immunex's
                  confidentiality obligations under the Tech Transfer Agreement.

         2.4      Amgen Confidentiality Obligations. Amgen agrees to be bound by
                  the confidentiality obligations imposed on Immunex under
                  Article 17 of the Agreement (as amended by this Amendment),
                  including without limitation the obligations contained in
                  Section 17.1(b), and the confidentiality obligations imposed
                  on Immunex under the Tech Transfer Agreement, in each case to
                  the same extent and with the same effect as if Amgen were the
                  party named therein and Genentech shall have the right to
                  enforce such obligations of confidentiality against Amgen as
                  if Amgen were a party to the Agreement and the Tech Transfer
                  Agreement.

3.       Immunity from Suit; Non-assertion.

         3.1      Genentech Reaffirmation. Genentech hereby restates and
                  reaffirms, for the benefit of Immunex and Amgen, all of
                  Genentech's obligations under Section 13.2 of the Agreement,
                  including without limitation the non-assertion obligations
                  contained in Sections 13.2(b)(2), 13.2(c)(1), and 13.2(c)(2);
                  and the Parties agree that Amgen is an intended third party
                  beneficiary of all such obligations to the same extent and
                  with the same effect as if Amgen were the party named therein,
                  and Amgen shall have the right to enforce such obligations
                  against Genentech as if Amgen were a party to the Agreement.

         3.2      Immunex Reaffirmation. Immunex hereby restates and reaffirms
                  all of Immunex's obligations under Section 13.2 of the
                  Agreement, including without limitation the nonassertion
                  obligations contained in Sections 13.2(b)(2), 13.2(c)(1) and
                  13.2(c)(2).

         3.3      Amgen Obligations. Amgen agrees to be bound by all of the
                  obligations imposed on Immunex under Section 13.2 of the
                  Agreement, including without limitation the nonassertion
                  obligations contained in Sections 13.2(b)(2), 13.2(c)(1), and
                  13.2(c)(2), to the same extent and with the same effect as if
                  Amgen were the party named therein, and Genentech shall have
                  the right to enforce such obligations against Amgen as if
                  Amgen were a party to the Agreement.

4.       Capitalized Terms. All capitalized terms used but not defined herein
         shall have the meaning set forth in the Agreement.

5.       Full Force and Effect. Except as set forth herein, all other terms of
         the Agreement remain in full force and effect.

6.       Counterparts; Facsimile; Further Amendment. This Amendment may be
         executed in any number of counterparts, each of which shall be deemed
         an original, and all of which, taken together, shall constitute one and
         the same instrument. This Amendment shall be effective upon full
         execution by facsimile or original, and a facsimile signature shall be
         deemed to be

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         and shall be as effective as an original signature. This Amendment may
         not be amended except by a written instrument duly executed and
         delivered by all Parties.

IN WITNESS WHEREOF, the Parties have executed this Amendment effective as of the
date set forth above.

GENENTECH, INC.                                 IMMUNEX CORPORATION

By:  /s/ David Ebersman                         By:  /s/ Efi Cohen-Arazi
    ---------------------------------------         ----------------------------
David Ebersman                                  Name: Efi Cohen-Arazi
Senior Vice President of Product Operations     Its: VP Manufacturing
Date: 2/3/03                                    Date: 2/9/03

AMGEN INC.

By: /s/ Dennis Fenton
    -------------------------------
Name: Dennis Fenton
Its: Executive Vice President
Date: 2/12/03

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