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EXHIBIT 99.0


CERTIFICATIONS 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

        In connection with the Annual Report of Titan Pharmaceuticals, Inc. (the "Company") on Form 10-K for the period ended December 31, 2002 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Louis R. Bucalo, M.D., Chairman, President and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. section 1350, as adopted pursuant to section 906 of the Sarbanes-Oxley Act of 2002, that, to the best of my knowledge:

        Signed at the City of South San Francisco, in the State of California, this 31st day of March, 2003.

    /s/  LOUIS R. BUCALO      
Louis R. Bucalo, M.D.

        In connection with the Annual Report of Titan Pharmaceuticals, Inc. (the "Company") on Form 10-K for the period ended December 31, 2002 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Robert E. Farrell, J.D., Executive Vice President and Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. section 1350, as adopted pursuant to section 906 of the Sarbanes-Oxley Act of 2002, that, to the best of my knowledge:

        Signed at the City of South San Francisco, in the State of California, this 31st day of March, 2003.

    /s/  ROBERT E. FARRELL      
Robert E. Farrell, J.D.



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CERTIFICATIONS 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