GVAX failure offers "lessons" for immunotherapy trials

Cell Genesys has released new data from VITAL-1, an abandoned Phase III  study of its GVAX prostate cancer vaccine which it says show some  "clinical activity," as well as "a favorable safety profile" compared to  Taxotere (docetaxel) chemotherapy, the standard-of-care for men with  advanced prostate cancer.

Last year, Cell Genesys and Japan-based Takeda's wholly-owned subsidiary  Millennium Pharmaceuticals mutually agreed to suspend their US GVAX  development deal for prostate cancer, after the termination of VITAL-2,  the second of two Phase III trials of GVAX, due to patient deaths  (Marketletter December 15, 2008).

The final Kaplan-Meier survival curves for the two treatment arms in  VITAL-1 suggest a late favorable effect of GVAX immunotherapy on patient  survival compared to chemotherapy, with the curve for GVAX patients  crossing above the chemotherapy curve at the same time median survival  was reached in both treatment arms (21 months). Additionally, the data  suggest that patients with Halabi predicted survival greater than or  equal to 18 months may have a more favorable response to the  immunotherapy.