At 9 am this morning, Dendreon Corporation (Nasdaq: DNDN) announced the long awaited interim analysis of the Phase 3, randomized, double-blind, placebo-controlled IMPACT (Immunotherapy for Prostate AdenoCarcinoma Treatment, also known as D9902B). The clinical trial is designed to assess the safety and efficacy of the investigational active cellular immunotherapy Provenge® (sipuleucel-T) in men with metastatic androgen-independent prostate cancer. The independent data monitoring committee (IDMC) reported to Dendreon a 20 percent reduction in the risk of death in the PROVENGE arm relative to placebo (Hazard Ratio= 0.80; 95% Confidence Interval [0.610-1.051]) . The IDMC observed no safety concerns and recommended that the study continue to its final analysis.

Mitchell H. Gold, M.D., president and chief executive officer of Dendreon said, “The treatment effect we have observed in this interim analysis is consistent with that observed in the integrated analysis of our previous Phase 3 trials in this patient population when analyzed at a similar 24-month follow-up time. Given the delayed treatment effect we have seen in previous studies, we are pleased to see evidence suggesting a prolongation of survival in the Provenge arm at the time of the interim analysis, as well as a favorable safety profile.”

The final analysis of the trial will not be made until the middle of 2009. Dendreon is hoping to see approximately a 22 percent reduction in the risk of death, based on 304 events. It does the studywill have met its primary endpoint of overall survival.
This IMPACT trial is a randomized, double-blind, placebo-controlled Phase 3 study which enrolled 512 men with metastatic, androgen-independent prostate cancer with a primary endpoint of overall survival. Despite the fact the U.S. Food and Drug Administration (FDA) Advisory Committee voted that there was substantial evidence of efficacy of Provenge and that it was reasonably safe, the FDA requested additional clinical data to support the proposed efficacy claim. The FDA did agree that a positive final analysis for overall survival from the IMPACT trial would be sufficient to meet its request for additional clinical information to support the proposed efficacy claim for Provenge.

You can learn more about the interesting and upsetting history of Provenge and the FDA by searching for Provenge in the search box above. The prior failure of the FDA to approve Provenge has caused a great rift between prostate cancer advocates and the FDA.

If you are interested in hearing a recording of the conference call you can call 1-888-203-1112 (domestic) or +1-719-457-0820 (international); the conference ID number is 5304314. The replay will be available from 2:00 p.m. ET on today (Monday), October 6 until midnight ET on Wednesday, October 8. In addition the webcast will be archived for on-demand listening for 30 days at www.dendreon.com.

Many of us applaud these interim results and are very excited about the potential Provenge may hold in the treatment of men with advanced prostate cancer.

Joel T Nowak MA, MSW