Biosante and Cell Genesys to merge after stockholders' approval

BioSante Pharmaceuticals, Inc. (NASDAQ: BPAX) and Cell Genesys, Inc. (NASDAQ: CEGE), today announced that each will hold a special stockholders meeting on September 30, 2009 at which time stockholders will be asked to approve the previously announced merger between the companies. On June 29, 2009, BioSante and Cell Genesys entered into a definitive merger agreement by which the companies will merge in an all-stock transaction, with BioSante as the surviving company.

A joint proxy statement/prospectus has been mailed to each stockholder of record of both companies and both boards of directors unanimously have recommended a vote “FOR” approval of the merger. BioSante and Cell Genesys stockholders as of the record date, August 21, 2009, are entitled to vote their shares at their respective special stockholders meeting.

Under the terms of the merger agreement, each share of Cell Genesys common stock held immediately prior to the effective time of the merger will be converted into 0.1615 of a share of BioSante common stock, subject to potential upward or downward adjustment, in accordance with a formula set forth in the merger agreement which is based on Cell Genesys’s net cash, less certain expenses and liabilities, on a date 10 calendar days preceding the anticipated closing date of the merger. As a result of the merger, BioSante will issue an aggregate of approximately 17.8 million shares of BioSante common stock to holders of Cell Genesys common stock and current BioSante stockholders will own approximately 65.0 percent of the outstanding common stock of the combined company and current Cell Genesys stockholders will own approximately 35.0 percent of the outstanding common stock of the combined company, assuming the 0.1615 exchange ratio is not adjusted and the number of outstanding shares of BioSante and Cell Genesys common stock remains unchanged until immediately prior to the effective time of the merger

Stephen M. Simes, president and CEO of BioSante, and Phillip B. Donenberg, CFO of BioSante, will continue to serve in those positions in the merged company. Dr. Louis W. Sullivan, chairman of the board of BioSante, will continue in that position. At closing, Stephen A. Sherwin, M.D., chairman and CEO of Cell Genesys, and John T. Potts, Jr., M.D., a current member of the Cell Genesys board, will join the board of directors of the merged company upon completion of the merger.

“This merger, combined with our recent $12 million financing, provides BioSante with the funding required for the continued Phase III development of LibiGel for FSD and offers the potential to expand our product development portfolio with the addition of GVAX Immunotherapies,” said Stephen M. Simes, BioSante’s president and CEO. “LibiGel remains the only pharmaceutical product in the U.S. in active development for the treatment of hypoactive sexual desire disorder (HSDD) in menopausal women. We continue to believe that LibiGel can be the first product approved by the FDA for the common and unmet medical need of FSD. In addition, our company has had a long-standing interest in immunotherapy based on our proprietary vaccine adjuvant, BioVant™, and we look forward to future value-creating opportunities for stockholders based on Cell Genesys’s technologies.”

“After reviewing various strategic alternatives, engaging in discussions with a number of other potential merger candidates and conducting extensive due diligence on BioSante’s product development and business activities, our board of directors has voted unanimously to recommend a merger with BioSante, “ stated Stephen A. Sherwin, M.D., chairman and CEO of Cell Genesys.

“We believe that BioSante’s lead product, LibiGel, represents a compelling near term product opportunity with significant upside potential. We also are impressed with BioSante’s record of achievement including the recent launch of Elestrin™ (estradiol gel) as well as their CaP nanotechnology platform which includes BioVant, a novel vaccine adjuvant with potential in immunotherapy,” Dr. Sherwin continued.