Dr. Petrylak Explains How Sipuleucel-T Impacts Survival

Daniel P. Petrylak, MD, director, Prostate and Genitourinary Cancer Program, co-director, Signal Transduction Research Program, at the Smilow Cancer Center at Yale-New Haven, discusses an analysis of three studies that found a correlation between immunological response and overall survival for men with castration-resistant prostate cancer being treated with the autologous cellular immunotherapy sipuleucel-T (Provenge).

The goal of this study was not to discover a predictive marker for sipuleucel-T, Petrylak explains. The analysis investigated the characteristics observed in 737 patients from three randomized, phase III trials. A correlation was found between overall survival and certain immune parameters, such as the number of antigen presenting cells (APC), APC activation or CD54 upregulation, and the total number of nucleated cells.

Petrylak explains that when examining the immune parameters associated with the sipuleucel-T mechanism of action a clear correlation between immune response and survival was observed. Overall, 78.8% of monitored patients demonstrated an antigen-specific immune response that correlated with a prolongation in overall survival.

This information may not necessarily have an impact on how sipuleucel-T is prescribed, Petrylak believes. However, it does answer many of the lingering questions about how sipuleucel-T works.