Following the FDA advisory committee vote that there was substantial evidence of efficacy of Provenge and that Provenge was reasonably safe, the FDA requested additional clinical data to support the proposed efficacy claim.
The FDA has previously agreed 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.
While Dendreon remains blinded to the data, the independent data monitoring committee (IDMC) reported to Dendreon a 20% 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.
At the final analysis, which is anticipated in the middle of 2009, if the study demonstrates approximately a 22% reduction in the risk of death, based on 304 events, the company would expect the study to meet its primary endpoint of overall survival.
Mitchell Gold, president and CEO of Dendreon, said: “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.”