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                                                                   Exhibit 10.59


                       RESTRICTED STOCK PURCHASE AGREEMENT

ROGER M. PERLMUTTER, Amgen Inc. Grantee:

          On this 8th day of January, 2001, Amgen Inc., a Delaware corporation
(the "Company"), pursuant to its Amended and Restated 1991 Equity Incentive Plan
(the "Plan") has granted to you, the grantee named above, a right to purchase
One Hundred Eleven Thousand Five Hundred (111,500) shares (the "Shares") of the
$.0001 par value common stock of the Company ("Common Stock") pursuant to the
terms of this Restricted Stock Purchase Agreement (this "Agreement") and the
Plan. Capitalized terms not defined herein shall have the meanings assigned to
such terms in the Plan.

          I.   Purchase Price. Subject to the terms and conditions of this
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Agreement, the Shares may be purchased from the Company at a purchase price per
share of $.0001 for a total purchase price of $11.15 (the "Total Purchase
Price"). The Total Purchase Price shall be paid in cash at the time of purchase.

          II.  Repurchase Option.
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               (1) Upon termination of your employment for any reason, other
than death and permanent and total disability (with such permanent and total
disability being certified by the Social Security Administration prior to such
termination), the Company shall have the right and option to purchase from you
or any holder of the Shares as permitted under Section III(5) (a "Holder") any
or all of the Shares at the per Share purchase price paid by you for such Shares
(the "Repurchase Option").

               (2) The Company may exercise the Repurchase Option by delivering
personally or by registered mail, to you or a Holder within ninety (90) days of
the date of termination of your employment, a notice in writing indicating the
Company's intention to exercise the Repurchase Option and setting forth a date
for closing not later than thirty (30) days from the mailing of such notice. The
closing shall take place at the Company's office. At the closing, the Secretary
of the Company or other escrow agent as provided in Section VI shall deliver the
stock certificate or certificates evidencing the Shares to the Company, and the
Company shall deliver the purchase price therefor.

               (3) At its option, the Company may elect to make payment for the
Shares to a bank selected by the Company. The Company shall avail itself of this
option by a notice in writing to you or a Holder stating the name and address of
the bank, date of closing, and waiving the closing at the Company's office.

               (4) If the Company does not elect to exercise the Repurchase
Option conferred above by giving the requisite notice to you or a Holder within
ninety (90) days

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following the date of termination of your employment, the Repurchase Option
shall terminate, and any restrictions on Shares remaining as of the date of the
termination of your employment shall lapse immediately.

               (5) One hundred percent (100%) of the Shares shall initially be
subject to the Repurchase Option. The Shares shall be released from the
Repurchase Option in accordance with the schedule set forth in Section III(1).

         III.  Lapse of Repurchase Option.
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               (1) Subject to Sections III (2), (3) and (4), the Repurchase
Option shall lapse in accordance with the following schedule with respect to the
Shares which have not previously been forfeited by you, provided you are
actively employed by the Company on the respective dates:

                                Number of Shares to Which Repurchase Option
                                -------------------------------------------
                   Date                         Shall Lapse
                   ----                         -----------
               April 1, 2002                    40,000
               April 1, 2003                    23,750
               April 1, 2004                    23,750
               April 1, 2005                    24,000

               (2) Upon termination of your employment due to your permanent and
total disability (with such permanent and total disability being certified by
the Social Security Administration prior to such termination) or your death,
then the Repurchase Option shall lapse immediately with respect to all the
Shares awarded under this Agreement. For purposes of this Agreement,
"termination of your employment" shall mean the last date you are either an
employee of the Company or an Affiliate or engaged as a consultant or director
to the Company or an Affiliate.

               (3) In addition, the lapsing of the Repurchase Option pursuant to
Section III(1) may be suspended during a leave of absence as provided from time
to time according to Company policies and practices.

               (4) Notwithstanding anything to the contrary contained herein,
the Committee may, as it deems appropriate, in its sole discretion, accelerate
the date on which the Repurchase Option shall lapse with respect to any of the
Shares which have not been previously forfeited by you.

               (5) Your Shares are not assignable or transferable, except by
will or the laws of descent and distribution. Notwithstanding the foregoing, all
or a portion of the Shares subject to the Repurchase Option may be transferred
to an Alternate Payee (as defined in the Plan) if required by the terms of a
QDRO (as defined in the Plan), as further described in the Plan; provided, that
such Alternate Payee is subject to the same terms and conditions as set forth in
this Agreement

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         IV.   Legends. Certificates representing the Shares issued pursuant to
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this Agreement shall, until all restrictions lapse or shall have been removed
and new certificates are issued pursuant to Section V, bear the following
legend:


     "THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
     CERTAIN RESTRICTIONS AND REPURCHASE RIGHTS AND MAY BE SUBJECT TO
     FORFEITURE UNDER THE TERMS OF THAT CERTAIN RESTRICTED STOCK
     PURCHASE AGREEMENT BY AND BETWEEN AMGEN INC. (THE "COMPANY") AND
     THE REGISTERED OWNER OF SUCH SHARES, AND SUCH SHARES MAY NOT BE,
     DIRECTLY OR INDIRECTLY, OFFERED, TRANSFERRED, SOLD, ASSIGNED,
     PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED OF UNDER ANY
     CIRCUMSTANCES, EXCEPT PURSUANT TO THE PROVISIONS OF SUCH
     AGREEMENT."

         V.    Issuance of Certificates; Tax Withholding.
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               (1) Subject to subsection (2) below, upon the lapse of the
Repurchase Option with respect to any of the Shares as provided in Section III,
the Company shall cause new certificates to be issued with respect to such
Shares and delivered to you or a Holder, free from the legend provided for in
Section IV and of the Repurchase Option. Such Shares shall cease to be subject
to the terms and conditions of this Agreement.

               (2) Notwithstanding subsection (1), no such new certificate shall
be delivered to you or a Holder unless and until you or a Holder shall have paid
to the Company, in cash or by check, the full amount of all federal and state
withholding or other employment taxes applicable to your taxable income
resulting from the grant of the Shares or the lapse or removal of the
restrictions in a form approved by the Committee.

         VI.   Escrow. The Secretary of the Company or such other escrow holder
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as the Committee may appoint shall retain physical custody of the certificates
representing the Shares until all of the restrictions lapse or shall have been
removed; provided, however, that in no event shall you retain physical custody
of any certificates representing Shares issued to you which are subject to the
Repurchase Option.

         VII.  No Contract for Employment. This Agreement is not an employment
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or service contract and nothing in this Agreement shall be deemed to create in
any way whatsoever any obligation on your part to continue in the employ or
service of the Company, or of the Company to continue your employment or service
with the Company.

         VIII. Notices. Any notices provided for in this Agreement or the Plan
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shall be given in writing and shall be deemed effectively given upon receipt or,
in the case of notices delivered by the Company to you, five (5) days after
deposit in the United States mail, postage prepaid, addressed to you at such
address as is currently maintained in the Company's records or at such other
address as you hereafter designate by written notice to the Company.

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          IX. Plan. This Agreement is subject to all the provisions of the Plan
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and its provisions are hereby made a part of this Agreement, including without
limitation the provisions of paragraph 7 of the Plan relating to purchases of
restricted stock, and is further subject to all interpretations, amendments,
rules and regulations which may from time to time be promulgated and adopted
pursuant to the Plan. In the event of any conflict between the provisions of
this Agreement and those of the Plan, the provisions of the Plan shall control.



                                             Very truly yours,
                                             AMGEN INC.

                                             By /s/ Steven M. Odre
                                               ------------------------------
                                             Duly authorized on behalf of the
                                             Board of Directors


Agreed and Accepted
as of the date first written above



/s/ Roger M. Perlmutter
-----------------------------
Roger M. Perlmutter

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