July 5, 2006

California-based Cell Genesys has announced that the results from a clinical trial of GVAX immunotherapy for prostate cancer in patients with early-stage disease have been published in the journal Clinical Cancer Research.

The Phase I/II trial enrolled 21 patients with rising prostate specific antigen (PSA) levels following prostatectomy and who had not received any other treatment for their prostate cancer, including hormone therapy. The results showed that 16 of 21 (76 percent) patients showed a statistically significant decrease in the rate of rise of PSA post-treatment compared with the remaining five patients. One patient had a partial PSA response of seven-month duration.

GVAX cancer immunotherapy was generally well-tolerated, with self-limited injection site reactions and mild flu-like symptoms being the most frequently reported side effects. In addition to clinical activity, the publication reported immunologic findings confirming that GVAX immunotherapy for prostate cancer resulted in the induction of immune responses as evidenced by the formation of antibodies directed against prostate cancer cells.