The US Food and Drug Administration (FDA) has assigned a Prescription Drug User Fee Act (PDUFA) action date of November 22, 2012 for the review of the investigational agent enzalutamide (formerly MDV3100) New Drug Application (NDA) for the potential treatment of men with castration-resistant prostate cancer previously treated with docetaxel-based chemotherapy.

On July, 2012 Medivation, Inc. and Astellas Pharma Inc. have announced that the Us FDA accepted the enzalutamide NDA filing for review and granted Priority Review Designation.

Enzalutamide is an oral, once-daily investigational agent that is an androgen receptor signalling inhibitor. Enzalutamide inhibits androgen receptor signalling in three distinct ways: it inhibits 1) testosterone binding to androgen receptors; 2) nuclear translocation of androgen receptors; and 3) DNA binding and activation by androgen receptors.

In the phase 3 AFFIRM trial common side effects observed more frequently in enzalutamide as compared with placebo-treated patients included fatigue, diarrhoea and hot flush. Seizure was reported in less than 1% of enzalutamide-treated patients. Serious adverse events, adverse events causing patients to stop treatment, and adverse events causing death all were lower in the enzalutamide group than in the placebo group.

Medivation, Inc. is a biopharmaceutical company focused on the rapid development of novel therapies to treat serious diseases for which there are limited treatment options.

Astellas Pharma Inc. is a pharmaceutical company dedicated to improving the health of people around the world through provision of innovative and reliable pharmaceuticals.