Callisto Pharmaceuticals Conference Call and Webcast:
Update on Annamycin with Dr. Hagop Kantarjian, held February 3, 2005

Callisto Pharmaceuticals, Inc., is a publicly traded biotechnology company on the American Stock Exchange (AMEX:KAL) and Frankfurt Exchange (CA4). Callisto’s primary focus is the clinical development of two drugs to treat cancer, Annamycin for relapsed leukemia and Atiprimod for relapsed multiple myeloma (MM) and bone resorption. Annamycin, a drug from the anthracycline family, earlier completed a Phase I/IIa trial in refractory leukemia patients. Callisto plans to initiate a Phase IIb trial in relapsed leukemia patients in the first half of 2005. Callisto’s second drug, Atiprimod, a small-molecule, orally available drug with antiproliferative and antiangiogenic activity, began an open-label Phase I/IIa clinical trial in relapsed MM patients on May 25, 2004.

Callisto also has drugs in preclinical development for melanoma, gastrointestinal inflammation, and a program focused on the development of a drug to protect against staphylococcus and streptococcus biowarfare agents. Callisto has two operating subsidiaries, Callisto Research Labs, LLC and Synergy Pharmaceuticals Inc. Callisto has exclusive worldwide licenses from AnorMED Inc. and M.D. Anderson Cancer Center to develop, manufacture, use and sell Atiprimod and Annamycin, respectively.