UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) [X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE QUARTERLY PERIOD ENDED: JUNE 30, 2005 [ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from __________ to __________ COMMISSION FILE NUMBER: 001-32325 CALLISTO PHARMACEUTICALS, INC. (Exact name of Registrant as specified in its charter) (Delaware) (13-3894575) ((State or Other Jurisdiction of) ((I.R.S. Employer Identification No.)) (Incorporation or Organization)) 420 Lexington Avenue, Suite 1609, New York, New York 10170 (Address of principal executive offices) (Zip Code) (212) 297-0010 (Registrant's telephone number) (Former Name, Former Address and Former Fiscal Year, if changed since last report) Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding twelve months (or for such shorter period that the registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days. (|X|) (|_|) (Yes) (No) (Indicate) (by check mark whether the registrant is an accelerated filer (as defined) (in Rule 12b-2 of the Exchange Act).) (|_| |X|) (Yes No) (As of August 1, 2005 the issuer had 31,238,893 shares of common stock outstanding.)