EXHIBIT 23.1 CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS We consent to the incorporation by reference in the Registration Statement (Form S-8 No. 333-42533) pertaining to the 1995 Stock Option Plan of Titan Pharmaceuticals, Inc., as amended and restated, of our report dated February 12, 1999, with respect to the consolidated financial statements of Titan Pharmaceuticals, Inc. included in the Annual Report (Form 10-K) for the year ended December 31, 1998. /s/ Ernst & Young LLP Palo Alto, California March 29, 1999