United States-based Pfizer and Japan-based Astellas Pharma have submitted a supplemental New Drug Application (NDA) to the US Food and Drug Administration (FDA) for Xtandi (enzalutamide), intended for a new indication and granted priority review designation, it was reported yesterday.

If approved, the supplemental NDA is to expand XTANDI's indication to include men with non-metastatic Castration-Resistant Prostate Cancer (CRPC), based on data from the Phase three PROSPER trial. Presently, XTANDI is indicated for the treatment of patients with metastatic CRPC. The FDA grants Priority Review designation to applications for drugs that, if approved, are likely to offer significant improvements in the safety and effectiveness of the treatment of serious conditions when compared to standard applications. Under Priority Review, the US FDA intends to take action on an application within six months of receipt, as compared to ten months under standard review.

The PROSPER trial assessed the product and androgen deprivation therapy compared with ADT alone in 1,401 patients with non-metastatic CRPC.

The FDA approved XTANDI in 2012 for the treatment of patients with metastatic CRPC who had previously received docetaxel. In 2014, the FDA approved XTANDI to treat patients with metastatic CRPC.