UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT FILED PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): DECEMBER 14, 2001 ZONAGEN, INC. (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER) DELAWARE 0-21198 76-0233274 (STATE OR OTHER JURISDICTION OF (COMMISSION FILE NUMBER) (I.R.S. EMPLOYER IDENTIFICATION NO.) INCORPORATION OR ORGANIZATION) 2408 TIMBERLOCH PLACE, SUITE B-4 THE WOODLANDS, TEXAS 77380 (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES AND ZIP CODE) (281) 719-3400 (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE) ITEM 5. OTHER EVENTS On December 14, 2001, Zonagen, Inc. issued a press release announcing that the preliminary interim results from the gross necropsies of both old and young rats exposed to various doses of phentolamine suggests that phentolamine does not induce or promote brown fat proliferations in the rat. This study was initiated in November of 2000 in an attempt to resolve the FDA's concerns regarding the appearance of brown fat proliferations in a prior two-year rat study. The press release is filed as an exhibit to this Current Report on Form 8-K and is incorporated by reference herein. ITEM 7. EXHIBITS Exhibit 99.1 -- Press Release dated December 14, 2001. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ZONAGEN, INC. Date: December 14, 2001 By: /s/ Louis Ploth, Jr. ------------------------------------ Louis Ploth, Jr. Vice President, Finance EXHIBIT INDEX Exhibit Number Description -------- ------------ 99.1 Press Release dated December 14, 2001.