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                                                        REGISTRATION NO. 33-9470
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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                         POST-EFFECTIVE AMENDMENT NO. 3
                                       TO
                                    FORM S-8
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                              AMGEN BOULDER INC.
             (Exact name of registrant as specified in its charter)

                      (FORMERLY KNOWN AS SYNERGEN, INC.)


                                                                           
                                    DELAWARE                                      84-0868248
                         (State or other jurisdiction of                       (I.R.S. Employer
                         incorporation or organization)                       Identification No.)
                                                                  
                       C/O AMGEN INC., AMGEN CENTER, 1840                         91320-1789
                      DEHAVILLAND DRIVE, THOUSAND OAKS, CA                        (Zip Code)
                    (Address of Principal Executive Offices)      
                                                          
                                                                  
                                                                  
                                                                  
                                                                  
                                 SYNERGEN, INC.                   
                          INCENTIVE AND NON-QUALIFIED             
                               STOCK OPTION PLAN                  
                            (Full title of the plan)              
                                                                  
                                                                  
                                                                  
                                                           
                                                              
         MARGARET VALEUR-JENSEN, PH.D.                                    With copies to:
                SENIOR COUNSEL                                       GEORGE A. VANDEMAN, ESQ.
                  AMGEN INC.                                             LATHAM & WATKINS
                 AMGEN CENTER                                    633 WEST FIFTH STREET, SUITE 4000
            1840 DEHAVILLAND DRIVE                                     LOS ANGELES, CA 90071
         THOUSAND OAKS, CA  91320-1789                                    (213) 485-1234
    (Name and address of agent for service)                       
                                                                  
                (805) 447-1000                                    
  (Telephone number, including area code, of
              agent for service)

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                 This Registration Statement No. 33-9470 (the "Registration
Statement") registered an aggregate of 459,667 shares of Common Stock, par
value $.01 (the "Securities"), of Amgen Boulder Inc. (formerly known as 
Synergen, Inc.) (the "Registrant").

                 On December 29, 1994, the Registrant became a wholly-owned
subsidiary of Amgen Inc. following a merger.  As a result of the merger, it is
anticipated that the Registrant's securities will no longer be registered under
the Securities Act of 1934, as amended.  Accordingly, the Registrant is
removing the Securities from registration under the Securities Act of 1933,
as amended.





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                                   SIGNATURE

                 Pursuant to the requirements of the Securities Act of 1933, as
amended, the Registrant has duly caused this Post-Effective Amendment No. 3 to
the Registration Statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of Thousand Oaks, State of California,
on March 6, 1995.

                                       AMGEN BOULDER INC.


                                       By:  /s/  THOMAS E. WORKMAN, JR.
                                            ---------------------------------
                                            Thomas E. Workman, Jr.
                                            Vice President, Secretary
                                            and General Counsel


                               POWER OF ATTORNEY

                 Each person whose signature appears below constitutes and
appoints Thomas E. Workman, Jr. his true and lawful attorney-in-fact and agent,
with full power of substitution and resubstitution, for him and in his name,
place and stead, in any and all capacities, to sign any and all amendments
(including post-effective amendments) to the Registration Statement amended by
this Post-Effective Amendment No. 3, and to file the same, with all exhibits
thereto and other documents in connection therewith, with the Securities and
Exchange Commission, granting unto said attorneys-in-fact and agents, and each
of them, full power and authority to do and perform each and every act and
thing requisite and necessary to be done in and about the premises, as fully to
all intents and purposes as he might or could do in person, hereby ratifying
and confirming all that said attorneys-in-fact and agents or any of them, or
their or his substitutes or substitute, may lawfully do or cause to be done by
virtue hereof.

                 Pursuant to the requirements of the Securities Act of 1933, as
amended, this Post-Effective Amendment No. 3 to the Registration Statement has 
been signed by the following persons in the capacities and on the dates 
indicated.



Signature                          Title                                         Date
- ---------                          -----                                         ----
                                                                           

/s/ GORDON M. BINDER
- -----------------------                                                  
Gordon M. Binder                   Chief Executive Officer                       March 13, 1995
                                   (Principal Executive Officer)         
                                                                         
/s/ ROBERT S. ATTIYEH                                                                         
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Robert S. Attiyeh                  Senior Vice President, Finance                March 13, 1995
                                   and Corporate Development 
                                   and Director          
                                   (Principal Financial and Accounting   
                                   Officer)                              
                                                                 
                        




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/s/ THOMAS E. WORKMAN, JR.
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Thomas E. Workman, Jr.                Vice President, Secretary,                March 6, 1995
                                      General Counsel and Director   
                                                                     
/s/ DR. N. KIRBY ALTON                                                                     
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Dr. N. Kirby Alton                    Director                                  March 13, 1995
                                                                     
/s/ DR. MICHAEL BEVILACQUA                                                                     
- ----------------------------                                             
Dr. Michael Bevilacqua                Director                                  March 14, 1995
                                                                     
/s/ Dr. GEORGE MORSTYN                                                                     
- ---------------------------                                              
Dr. George Morstyn                    Director                                  March 13, 1995
                                                                     
/s/ DR. DANIEL VAPNEK                                                                     
- ---------------------------                                              
Dr. Daniel Vapnek                     Director                                  March 13, 1995
                                                             



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