The good news is that finally Astellas and Medivation have submitted a supplemental New Drug Application (sNDA) to the U.S. Food and Drug Administration (FDA) seeking approval of XTANDI (enzalutamide) for the treatment of men with metastatic castration-resistant prostate cancer (mCRPC) who have not received chemotherapy. As of today XTANDI is currently only approved for the treatment of men with mCRPC who have previously received docetaxel chemotherapy. Despite this, many men have been able to access Xtandi “off label” but this approval would make the process easier.
The sNDA application is based on the results from the Phase 3 PREVAIL trial evaluating XTANDI as compared to placebo in more than 1,700 chemotherapy-naive men withmCRPC. A similar marketing authorization application should be submitted to the European Medicines Agency later this year.
We believe that given the statistical results of the PREVAIL trial it should be easily approved by the FDA and the European Medicines Agency. However, the approval will make even more complex the decision making process that will be required by doctors, patients and insurance companies when they will have to consider both Xtandi and Zytiga along side of each other in the pre-chemotherapy space.
Joel T Nowak, M.A., M.S.W.