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                                                                     EXHIBIT 4.5

                                     Form of 4.00% Senior Notes due 2009

                                 [Face of Note]
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                                                          CUSIP/CINS ___________

                           4.00% Senior Notes due 2009

No. ___                                                            $____________

                                   AMGEN INC.

promises to pay to CEDE & CO. or registered assigns,

the principal sum of _____________________ on November 18, 2009.

Interest Payment Dates: May 18 and November 18

Record Dates: 15th day prior to May 18 and November 18

Dated:

                                          AMGEN INC.

                                          By: __________________________________
                                              Name:
                                              Title:

                                          By: __________________________________
                                              Name:
                                              Title:

This is one of the Notes referred to
in the within-mentioned Indenture:

JPMorgan Chase Bank, N.A.,
 as Trustee

By: ____________________________________
            Authorized Officer

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                                 [Back of Note]
                           4.00% SENIOR NOTES DUE 2009

      THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITORY OR A
NOMINEE OF THE DEPOSITORY. THIS SECURITY IS EXCHANGEABLE FOR SECURITIES
REGISTERED IN THE NAME OF A PERSON OTHER THAN THE DEPOSITORY OR ITS NOMINEE ONLY
IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE, AND MAY NOT BE
TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITORY TO A NOMINEE OF THE DEPOSITORY,
BY A NOMINEE OF THE DEPOSITORY TO THE DEPOSITORY OR ANOTHER NOMINEE OF THE
DEPOSITORY OR BY THE DEPOSITORY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITORY OR
A NOMINEE OF SUCH A SUCCESSOR DEPOSITORY.

      Capitalized terms used herein have the meanings assigned to them in the
Indenture referred to below unless otherwise indicated.

            (1) INTEREST. Amgen Inc., a Delaware corporation (the "Company"),
      promises to pay interest on the principal amount of this Note at 4.00% per
      annum from November 18, 2004 until maturity and shall pay the Special
      Interest (as defined in the Registration Rights Agreement), if any,
      payable pursuant to Section 4 of the Registration Rights Agreement
      referred to below. The Company will pay interest and Special Interest, if
      any, semi-annually in arrears on May 18 and November 18 of each year, or
      if any such day is not a Business Day, on the next succeeding Business Day
      (each, an "Interest Payment Date"). Interest on the Notes will accrue from
      the most recent date to which interest has been paid or, if no interest
      has been paid, from the date of issuance; provided that the first Interest
      Payment Date shall be May 18, 2005; provided further that after May 18,
      2005, if there is no existing Default in the payment of interest, and if
      this Note is authenticated between a record date referred to on the face
      hereof and the next succeeding Interest Payment Date, interest shall
      accrue from such next succeeding Interest Payment Date.

            (2) METHOD OF PAYMENT. The Company will pay interest on the Notes
      (except defaulted interest) and Special Interest, if any, to the Persons
      who are registered Holders of Notes at the close of business on the day
      that is 15 days prior to the next succeeding Interest Payment Date
      (whether or not such day is a Business Day), even if such Notes are
      canceled after such record date and on or before such Interest Payment
      Date, except as provided in Section 2.13 of the Indenture with respect to
      defaulted interest. The Notes will be payable as to principal, interest
      and Special Interest, if any, at the office or agency of the Company
      maintained for such purpose in the Borough of Manhattan, the City and
      State of New York (or, if the Company fails to maintain such office or
      agency, at the corporate trust office of the trustee in New York, New York
      or if the trustee does not maintain an office in New York, at the office
      of a paying agent in New York), or, at the option of the Company, payment
      of interest and Special Interest, if any, may be made by check mailed to
      the Holders at their addresses set forth in the register of Holders;
      provided that payment by wire transfer of immediately available funds will
      be required with respect to principal of and interest and Special
      Interest, if any, on, all Global Securities and all other Notes the
      Holders of which will have provided wire transfer instructions to the
      Company or the Paying Agent. Such payment will be in the currency of the
      United States of America.

            (3) PAYING AGENT AND REGISTRAR. Initially, JPMorgan Chase Bank,
      N.A., the Trustee under the Indenture, will act as Paying Agent and
      Registrar. The Company may change any

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      Paying Agent or Registrar without notice to any Holder. The Company or any
      of its Subsidiaries may act in any such capacity.

            (4) INDENTURE. The terms of the Notes include those stated in the
      Indenture and those made part of the Indenture by the Officers'
      Certificate dated November 18, 2004 delivered pursuant thereto (the
      "Officers' Certificate") and the TIA. The Notes are subject to all such
      terms, and the Holders are referred to the Indenture and the TIA for a
      statement of them.

            (5) OPTIONAL REDEMPTION. At any time prior to maturity, the Company
      will have the option to redeem all or a part of the Notes upon not less
      than 30 nor more than 60 days' notice, at a redemption price equal to the
      sum of (1) 100% of the principal amount of any notes being redeemed plus
      accrued and unpaid interest to, but not including, the redemption date,
      and (2) the Make-Whole Amount. Unless the Company defaults in the payment
      of the redemption price, interest will cease to accrue on the Notes or
      portions thereof called for redemption on the applicable redemption date.

            (6) MANDATORY REDEMPTION. The Company is not required to make
      mandatory redemption or sinking fund payments with respect to the Notes.

            (7) NOTICE OF REDEMPTION. Notice of redemption will be mailed at
      least 30 days but not more than 60 days before the redemption date to each
      Holder whose Notes are to be redeemed at its registered address, except
      that redemption notices may be mailed more than 60 days prior to a
      redemption date if the notice is issued in connection with a defeasance of
      the Notes or a satisfaction or discharge of the Indenture. Notes in
      denominations larger than $1,000 may be redeemed in part but only in whole
      multiples of $1,000, unless all of the Notes held by a Holder are to be
      redeemed.

            (8) DEFEASANCE PRIOR TO MATURITY. The Indenture contains provisions
      for defeasance of (i) the entire indebtedness of the Notes or (ii) certain
      covenants and Events of Default with respect to the Notes, in each case
      upon compliance with certain conditions set forth therein.

            (9) RESTRICTIVE COVENANTS. The Indenture and the Officers'
      Certificate impose certain limitations on the Company's and its
      Subsidiaries', including limitations on the Company's and its subsidiaries
      ability to create or incur certain Liens on any of their respective
      properties or assets and to enter into certain sale and lease-back
      transactions and on the Company's ability to engage in mergers or
      consolidations or the conveyance, transfer or lease of all or
      substantially all of its properties and assets. These limitations are
      subject to a number of important qualifications and exceptions and
      reference is made to the Indenture and the Officers' Certificate for a
      description thereof.

            (10) DENOMINATIONS, TRANSFER, EXCHANGE. The Notes are in registered
      form without coupons in denominations of $1,000 and integral multiples of
      $1,000. The transfer of Notes may be registered and Notes may be exchanged
      as provided in the Indenture. The Registrar and the Trustee may require a
      Holder, among other things, to furnish appropriate endorsements and
      transfer documents and the Company may require a Holder to pay any taxes
      and fees required by law or permitted by the Indenture. The Company need
      not exchange or register the transfer of any Note or portion of a Note
      selected for redemption, except for the unredeemed portion of any Note
      being redeemed in part. Also, the Company need not exchange or register
      the transfer of any Notes for a period of 15 days before a selection of
      Notes to be redeemed or during the period between a record date and the
      corresponding Interest Payment Date.

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            (11) PERSONS DEEMED OWNERS. The registered Holder of a Note may be
      treated as its owner for all purposes.

            (12) AMENDMENT, SUPPLEMENT AND WAIVER. Subject to certain
      exceptions, the Indenture or the Notes may be amended or supplemented with
      the consent of the Holders of at least a majority in aggregate principal
      amount of the then outstanding Notes voting as a single class, and any
      existing Default or Event or Default or compliance with any provision of
      the Indenture or the Notes may be waived with the consent of the Holders
      of a majority in aggregate principal amount of the then outstanding Notes
      voting as a single class. Without the consent of any Holder of a Note, the
      Indenture or the Notes may be amended or supplemented to cure any
      ambiguity, defect or inconsistency, to provide for uncertificated Notes in
      addition to or in place of certificated Notes, to make any change that
      would not adversely affect the legal rights under the Indenture of any
      such Holder, to provide for the issuance of any additional notes as
      permitted by the Indenture, to appoint a successor trustee with respect to
      the notes and to add to or change any of the provisions of the Indenture
      necessary to provide for the administration of the trusts in the indenture
      by more than one trustee, or to comply with the requirements of the SEC in
      order to effect or maintain the qualification of the Indenture under the
      TIA.

            (13) DEFAULTS AND REMEDIES. If an Event of Default shall occur and
      be continuing, the principal of the Notes may be declared (or, in certain
      cases, shall ipso facto become) due and payable in the manner and with the
      effect provided in the Indenture.

            (14) TRUSTEE DEALINGS WITH COMPANY. The Trustee under the Indenture,
      in its individual or any other capacity, may deal with the Company or an
      Affiliate of the Company with the same rights it would have if it were not
      Trustee.

            (15) NO RECOURSE AGAINST OTHERS. A director, officer, employee or
      stockholder of the Company shall not have any liability for any
      obligations of the Company under the Notes or the Indenture or for any
      claim based on, in respect of, or by reason of, such obligations or their
      creation. Each Holder by accepting a Note waives and releases all such
      liability. The waiver and release are part of the consideration for the
      issuance of the Notes.

            (16) AUTHENTICATION. This Note will not be valid until authenticated
      by the manual signature of the Trustee or an authenticating agent.

            (17) ABBREVIATIONS. Customary abbreviations may be used in the name
      of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN
      ENT (= tenants by the entireties), JT TEN (= joint tenants with right of
      survivorship and not as tenants in common), CUST (= Custodian), and
      U/G/M/A (= Uniform Gifts to Minors Act).

            (18) CUSIP NUMBERS. Pursuant to a recommendation promulgated by the
      Committee on Uniform Security Identification Procedures, the Company has
      caused CUSIP numbers to be printed on the Notes, and the Trustee may use
      CUSIP numbers in notices of redemption as a convenience to Holders. No
      representation is made as to the accuracy of such numbers either as
      printed on the Notes or as contained in any notice of redemption, and
      reliance may be placed only on the other identification numbers placed
      thereon.

            (19) GOVERNING LAW. THE INTERNAL LAW OF THE STATE OF NEW YORK WILL
      GOVERN AND BE USED TO CONSTRUE THE INDENTURE AND THIS NOTE WITHOUT GIVING
      EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO

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      THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD
      BE REQUIRED THEREBY.

      The Company will furnish to any Holder upon written request and without
charge a copy of the Indenture and/or the Registration Rights Agreement.
Requests may be made to:

                                   Amgen Inc.
                             One Amgen Center Drive
                          Thousand Oaks, CA 91320-1799
                          Attention: Investor Relations

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                                 ASSIGNMENT FORM

      To assign this Note, fill in the form below:

(I)or (we)assign and transfer this Note to:_____________________________________
                                              (Insert assignee's legal name)
________________________________________________________________________________
                 (Insert assignee's soc. sec. or tax I.D. no.)

________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
             (Print or type assignee's name, address and zip code)

and irrevocably appoint ________________________________________________________
to transfer this Note on the books of the Company. The agent may substitute
another to act for him.

Date: _______________

                                    Your Signature: ____________________________
                                           (Sign exactly as your name appears on
                                           the face of this Note)

Signature Guarantee*: _________________________

*           Participant in a recognized Signature Guarantee Medallion Program
(or other signature guarantor acceptable to the Trustee).

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