Astex Pharmaceuticals (SUPG) 10-Q 2003 Q1 Quarterly report

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EXHIBIT 99.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

I, Joseph Rubinfeld, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of SuperGen, Inc. on Form 10-Q for the quarterly period ended March 31, 2003 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that information contained in such Form 10-Q fairly presents in all material respects the financial condition and results of operations of SuperGen, Inc.

By:	/s/  JOSEPH RUBINFELD
Name:	Joseph Rubinfeld
Title:	President and Chief Executive Officer

I, Edward Jacobs, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the Quarterly Report of SuperGen, Inc. on Form 10-Q for the quarterly period ended March 31, 2003 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that information contained in such Form 10-Q fairly presents in all material respects the financial condition and results of operations of SuperGen, Inc.

By:	/s/  EDWARD JACOBS
Name:	Edward Jacobs
Title:	Chief Business Officer and Chief Financial Officer

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EXHIBIT 99.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002