Callisto Corporate Video Presentation Focuses on Company's Anti-Cancer Drug Candidates as Second Clinical Trial Starts; Video Presentation Spotlights Company's Drug Candidates to Treat Relapsed Leukemia and Multiple Myeloma Cancers.

NEW YORK -- Callisto Pharmaceuticals, Inc. (AMEX:KAL) (FWB:CA4), a developer of new drug treatments in the fight against cancer and other major health threats, has released a corporate video presentation outlining the Company's current lead anti-cancer drug candidates, Atiprimod and L-Annamycin. Following the recent milestone launch of human clinical trials of L-Annamycin, Callisto now has advanced two new drug candidates undergoing human clinical trials. E[acute accent]CEO Dr. Gary S. Jacob outlines Callisto's drug development programs in the corporate video. He describes some of the key anticipated medical and marketplace advantages of Atiprimod and L-Annamycin, which are being developed as treatments for relapsed multiple myeloma and relapsed leukemia, respectively. Patients are referred to as "relapsed" when they are no longer in remission and fail to respond to any approved chemotherapy treatment options. E[acute accent]"Callisto is excited to have moved two new drug candidates into the clinical trial phase to treat these desperately ill relapsed patients," said Dr. Jacob. "We plan to follow these achievements with strategic initiatives to expand our pipeline of drugs to treat cancer, related diseases and other major health markets." E[acute accent]The recently commenced human trial of L-Annamycin is a critical step in Callisto's efforts to bring this proprietary drug to the marketplace for patients with relapsed or refractory acute lymphocytic leukemia (ALL). The trial is being conducted at The University of Texas M. D. Anderson Cancer Center in Houston, Texas, one of the world's most respected cancer research institutions.

E[acute accent]Webalert: Investor Conference Call

E[acute accent]Callisto will host an investor conference call on Monday, December 12, at 12 noon Eastern, to discuss the Company's new Division of Intellectual Property, and provides an update on recent clinical and preclinical developments. E[acute accent]Callisto recently announced the formation of a new Division of Intellectual Property to spearhead growth of the Company's pipeline of new drug candidates, while broadening protection of its intellectual property portfolio through creation of multiple patents around broad classes of new drugs, as well as narrowly-focused claims on specific compounds. E[acute accent]To participate in the Conference Call: Callers in the United States may dial 888-428-4479 to listen and participate in the conference call. International callers can dial 612-234-9959. When prompted, please tell the operator that you would like to connect to the "Callisto Conference" call. This call is free of charge to all interested investors. In addition, interested investors can listen to the call via streaming audio over the web at http://www.trilogy-capital.com/kal_conference.html. The call will subsequently be archived for access via streaming audio at the same web link. E[acute accent]To view the Callisto corporate video, please visit http://www.trilogy-capital.com/tcp/callisto/video.html.

E[acute accent]About Callisto Pharmaceuticals, Inc.

E[acute accent]Callisto is a biopharmaceutical company focused on the development of new drugs to treat various forms of cancer and other serious afflictions. Callisto's drug candidates in development currently include anti-cancer agents in clinical development, in addition to drugs for a range of other significant health care market segments, including biodefense. One of the Company's lead drug candidates, L-Annamycin, is being developed as a treatment for forms of relapsed leukemia, a currently incurable blood cancer. Callisto initiated a clinical trial of L-Annamycin in adult relapsed acute lymphocytic leukemia patients in 4Q 2005. L-Annamycin, a new compound from the anthracycline family of proven anti-cancer drugs, has a novel therapeutic profile, including activity against resistant diseases and significantly reduced cardiotoxicity, or damage to the heart, compared to currently available drug alternatives. Another anti-cancer drug, Atiprimod, is in development to treat relapsed multiple myeloma, a blood cancer. Atiprimod has entered Phase I/IIa human clinical trials in relapsed multiple myeloma patients. Callisto also has drugs in preclinical development for gastro-intestinal inflammation, and a program focused on the development of a drug to protect against Staphylococcus and Streptococcus biowarfare agents. Callisto has exclusive worldwide licenses from AnorMED Inc. and M.D. Anderson Cancer Center to develop, manufacture, use and sell Atiprimod and L-Annamycin, respectively. For investor-specific information about Callisto, including recent news and stock price data, please visit http://www.trilogy-capital.com/tcp/callisto/. For an Investor Fact Sheet about Callisto, please visit http://www.trilogy-capital.com/tcp/callisto/factsheet.html. To view an informational presentation of the Company's development pipeline of drug candidates, visit http://www.trilogy-capital.com/tcp/callisto/powerpoint.html. Callisto is also listed on the Frankfurt Stock Exchange under the ticker symbol CA4. For additional information, visit www.callistopharma.com.

E[acute accent]Forward-Looking Statements

E[acute accent]Certain statements made in this press release are forward-looking. Such statements are indicated by words such as "expect," "should," "anticipate" and similar words indicating uncertainty in facts and figures. Although Callisto believes that the expectations reflected in such forward-looking statements are reasonable, it can give no assurance that such expectations reflected in such forward-looking statements will prove to be correct. As discussed in the Callisto Pharmaceuticals Annual Report on Form 10-K/A for the year ended December 31, 2004, and other periodic reports, as filed with the Securities and Exchange Commission, actual results could differ materially from those projected in the forward-looking statements as a result of the following factors, among others: uncertainties associated with product development, the risk that products that appeared promising in early clinical trials do not demonstrate efficacy in larger-scale clinical trials, the risk that Callisto will not obtain approval to market its products, the risks associated with dependence upon key personnel and the need for additional financing.