UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

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FORM 10-K/A

|ý                                                        | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934    
|-------------------------------------------------------- | ----------------------------------------------------------------------------------------
|For the Fiscal Year Ended December 31, 2003             
|OR                                                      
|o                                                        | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|For the transition period
from                        to

Commission file number 0-27628

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SUPERGEN, INC.(Exact name of registrant as specified in its charter)

|Delaware(State or other jurisdiction of incorporation or organization)           |  | 91-1841574(IRS Employer Identification Number)
|-------------------------------------------------------------------------------- |  | ----------------------------------------------
|4140 Dublin Blvd., Suite 200, Dublin, CA(Address of principal executive offices) |  | 94568(Zip Code)                               

Registrant's
telephone number, including area code:(925) 560-0100

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Securities
registered pursuant to Section 12(b) of the Act:None

Securities
registered pursuant to Section 12(g) of the Act:

Common Stock, $0.001 par value per share(Title of Class)

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Indicate
by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the
preceding 12 months (or for such shorter period that the registrant was required to file such reports) and (2) has been subject to such filing requirements for the past
90 days. Yes ý    No o

Indicate by check mark whether Registrant is an accelerated filer (as defined in Rule 12b-2 of the
Act). Yes ý    No o

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be
contained, to the best of the Registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment
to this Form 10-K.     ý

The aggregate market value of the voting stock held by non-affiliates of the Registrant (based on the closing sale price of the Common Stock as
reported on the Nasdaq Stock Market on June 30, 2003, the last business day of the Registrant's most recently completed second fiscal quarter) was approximately $178,517,248. This determination
of affiliate status is not necessarily a conclusive determination for other purposes. The number of outstanding shares of the Registrant's Common Stock as of the close of business on
February 27, 2004 was 38,470,198.

DOCUMENTS INCORPORATED BY REFERENCE

Items
10, 11, 12, 13 and 14 of Part III incorporate by reference information from the definitive proxy statement for the Registrant's Annual Meeting of Stockholders to be held on
May 6, 2004.



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EXPLANATORY NOTE

This Amendment No. 1 to SuperGen, Inc.'s Annual Report on Form 10-K for the fiscal year ended December 31, 2003 is being
filed solely for the purpose of correcting certain errors in Exhibits 31.1 and 31.2 to such Form 10-K filed electronically with the Securities and Exchange Commission on
March 4, 2004. The amended certifications are intended to replace the incorrect certifications, and no other changes are being made by means of this filing.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Exchange Act, the registrant caused this Report on Form 10-K to be signed on
its behalf by the undersigned, thereunto duly authorized, on this 29th day of March 2004.

| |  | SUPERGEN, INC.
| |  | --------------
| |  | By:           

Pursuant
to the requirements of the Exchange Act, this Report on Form 10-K has been signed by the following persons in the capacities and on the dates indicated.

|Signatures                              |  | Title                                                                         |  | Date          
|--------------------------------------- |  | ----------------------------------------------------------------------------- |  | --------------
|/s/JAMES S. J. MANUSOJames S. J. Manuso |  | Chief Executive Officer,
President and Director (Principal
Executive Officer) |  | March 29, 2004
|/s/MICHAEL MOLKENTINMichael Molkentin   |  | Chief Financial Officer
(Principal Financial and Accounting
Officer)          |  | March 29, 2004
|*Charles Casamento                      |  | Director                                                                      |  | March 29, 2004
|*Thomas V. Girardi                      |  | Director                                                                      |  | March 29, 2004
|*Walter J. Lack                         |  | Director                                                                      |  | March 29, 2004
|*Joseph Rubinfeld                       |  | Director                                                                      |  | March 29, 2004
|*Michael Young                          |  | Director                                                                      |  | March 29, 2004

|     |  |                                      |  | 
|---- |  | ------------------------------------ |  | 
|*By: |  | /s/MICHAEL MOLKENTINAttorney-in-fact |  | 

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