Astellas Pharma and Medivation announced that the FDA has accepted for filing the supplemental New Drug Application (sNDA) to extend the indication for Xtandi (enzalutamide) capsules for the treatment of men with metastatic castration-resistant prostate cancer (mCRPC) who have not received chemotherapy.
The submission was based on results from the Phase 3 PREVAIL trial evaluating Xtandi as compared to placebo in more than 1,700 chemotherapy-naïve mCRPC patients. The Phase 3 PREVAIL trial is a randomized, double-blind, placebo-controlled, multi-national trial that enrolled patients with chemotherapy-naive metastatic prostate cancer whose disease progressed on a luteinizing hormone-releasing hormone analogue or after bilateral orchiectomy. The co-primary endpoints of the trial were overall survival and radiographic progression-free survival. The trial was designed to evaluate enzalutamide at a dose of 160mg taken orally once daily vs. placebo.
Xtandi is already approved for the treatment of patients with mCRPC who have previously received docetaxel chemotherapy. Enzalutamide is an androgen receptor inhibitor that acts on different steps in the androgen receptor signaling pathway. It has been shown to competitively inhibit androgen binding to androgen receptors, and inhibit androgen receptor nuclear translocation and interaction with DNA.