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                                                                   Exhibit 10.54

                             SECOND AMENDMENT TO THE
                                   AMGEN INC.
                        CHANGE OF CONTROL SEVERANCE PLAN

     This Second Amendment to the Amgen Inc. Change of Control Severance Plan is
adopted as of October 16, 2001 by the Board of Directors (the "Board") of Amgen
Inc., a Delaware corporation (the "Company").

                                    RECITALS

     WHEREAS, the Company maintains the Amgen Inc. Change of Control Severance
Plan, effective as of October 20, 1998, (hereinafter the "Plan"); and

     WHEREAS, pursuant to section 11.3 of the Plan, the Company may amend the
Plan from time to time by resolution of the Board;

     NOW THEREFORE, BE IT RESOLVED, that the Plan be amended as follows,
effective January 1, 2002:

     1. Section 1(M) shall be amended and restated in its entirety as follows:

        "(M) "Group I Participants" shall mean those senior executive-level
        staff members of the Company and of Amgen USA Inc. whom the Company has
        designated as members of the Amgen Executive Committee, as such
        committee shall be constituted immediately prior to a Change of Control.
        At or before the occurrence of a Change of Control, the Company shall
        notify the Group I Participants in writing of their status as
        Participants in the Plan."

     2. Section 1(N) shall be amended and restated in its entirety as follows:

        "(N) "Group II Participants" shall mean those management-level staff
        members of the Company and of Amgen USA Inc. at the level of Director or
        equivalent and above (i.e., those employees of the Company or of Amgen
        USA Inc. whose positions have been designated as Salary Grade 32 or
        Salary Grade EL4 and above) and who are not Group I Participants, as
        such group shall be constituted immediately prior to a Change of
        Control. At or before the occurrence of a Change of Control, the Company
        shall notify the Group II Participants in writing of their status as
        Participants in the Plan."

     3. Section 1(O) shall be amended and restated in its entirety as follows:

        "(O) "Group III Participants" shall mean those management-level staff
        members of the Company and of Amgen USA Inc. at the level of Associate
        Director or equivalent (i.e., those employees of the Company or of Amgen
        USA Inc. whose positions have been designated as Salary Grade 30 or
        Salary Grade


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         EL2 or Salary Grade EL3), as such group shall be constituted
         immediately prior to a Change of Control. At or before the occurrence
         of a Change of Control, the Company shall notify the Group III
         Participants in writing of their status as Participants in the Plan."


     I hereby certify that the foregoing Second Amendment to the Plan was duly
adopted by the Board of Directors of Amgen Inc. on October 24, 2001
                                                           --


                                    AMGEN INC.

                                    By: /s/ Brian McNamee
                                       -----------------------------------------
                                    Title: Senior Vice President Human Resources
                                           -------------------------------------

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