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                                                                   Exhibit 10.58

                       RESTRICTED STOCK PURCHASE AGREEMENT

RICHARD NANULA, Amgen Inc. Grantee:

          On this 16th day of May, 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 Eighty
Five Thousand (85,000) 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 $8.50 (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)  Subject to Section III(4), 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 to you or a Holder.

               (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 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.

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               (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
                   ----                          -----------
               May 16, 2004                         20,000
               May 16, 2005                         20,000
               May 16, 2006                         45,000

               (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)  Upon termination of your employment by Amgen without Cause,
the Repurchase Option shall automatically lapse with respect to a pro rata
portion of each tranche of restricted stock for which the Repurchase Option was
otherwise scheduled to lapse as set forth in Section III(1), multiplied by the
ratio of (x) the sum of the number of full months of your active employment with
the Company and (y) the number of months otherwise required for lapsing of the
Repurchase Option with respect to such tranche, as follows:

               Number of Shares                   Ratio
               ----------------                   -----
                    20,000           x            Z/36
                    20,000           x            Z/48
                    45,000           x            Z/60

where Z= the sum of the number of full months of your active employment with the
Company.

               Solely for the purpose of this Agreement, "Cause" means (i) your
conviction of a felony, (ii) the engaging by you in conduct that constitutes
willful gross neglect


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or willful gross misconduct in carrying out your duties to the Company,
resulting, in either case, in material economic harm to the Company, unless you
believed in good faith that such conduct was in, or not contrary to, the best
interests of the Company, (iii) your material breach of any of the terms of this
letter agreement or the Proprietary Information and Inventions Agreement or (iv)
your failure to follow any lawful directive of the Company's Chief Executive
Officer with respect to your employment. For purposes hereof, no act, or failure
to act, on your part shall be deemed "willful" unless done, or omitted to be
done, by you not in good faith.

               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

          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.


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               VI.    Escrow. The Secretary of the Company or such other escrow
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holder 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, including, without limitation, the Repurchase Option.

               VII.   No Contract for Employment. This Agreement is not an
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employment 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
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Plan 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.

               IX.    Plan. This Agreement is subject to all the provisions of
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the Plan 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/ Richard Nanula
_________________________________
Richard Nanula


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