Cell Genesys reports antitumor activity in Phase I/II GVAX lung cancer vac...( SAN FRANCISCO Calif. May 13 2001Ce...)

SAN FRANCISCO, Calif., May 13, 2001Cell Genesys, Inc. (Nasdaq: CEGE) today reported interim clinical data from its multicenter Phase I/II GVAX lung cancer vaccine trial which demonstrates objective evidence of antitumor activity including a major response rate of 18 percent in patients with advanced non small-cell lung cancer who have failed chemotherapy and/or radiation therapy. These data were presented on behalf of the GVAX Lung Cancer Clinical Investigators by John Nemunaitis, M.D. of U.S. Oncology at the American Society of Clinical Oncology (ASCO) Meeting in San Francisco, Calif. The presentation was one of 17 selected for ASCOs Official Press Program from the more than 3,300 submitted to the meeting.

The interim clinical trial data includes results on 30 currently evaluable patients with advanced or early-stage lung cancer. Of 22 patients with advanced-stage lung cancer, three patients, two of whom had failed chemotherapy and one who failed radiation therapy, showed a complete disappearance of metastatic tumors following treatment with GVAX lung cancer vaccine. One other patient who failed radiation and chemotherapy had partial (greater than 50 percent) reduction in his tumor. In addition to these major responses, four patients currently have stable (non-progressive) disease. All of these responses are continuing with a median follow-up time of approximately five months. In addition to the responses in patients with advanced disease, seven of eight patients with early-stage lung cancer who received GVAX vaccine following surgery, currently remain free of disease with a median follow-up time of seven months.

We are very encouraged by what we have seen to date with GVAX lung cancer vaccine, particularly with respect to the major tumor responses in patients with metastatic lung cancer who have failed chemotherapy, stated Dr. Nemunaitis. These findings are all the more noteworthy given that lung cancer patients who fail chemotherapy have little c
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Contact: Todd Ringler
tringler@fkhealth.com
617-761-6791
Feinstein Kean Healthcare
12-May-2001