Healthcare company Astellas Pharma Inc (TSE:4503) and Pfizer Inc (NYSE:PFE) Wednesday jointly filed a supplemental New Drug Application (sNDA) for XTANDI (enzalutamide) with the US Food and Drug Administration (FDA) for the treatment of men with metastatic hormone-sensitive prostate cancer (mHSPC) under the FDA's priority review designation, with a Prescription Drug User Fee Act (PDUFA) date in Q4 2019.

Currently, TANDI is indicated in the US for the treatment of patients with castration-resistant prostate cancer (CRPC). In men with prostate cancer, the disease is considered metastatic once the cancer has spread outside of the prostate gland to other parts of the body.

XTANDI is an androgen receptor inhibitor indicated for the treatment of patients with castration-resistant prostate cancer.

Based on results from the Phase 3 ARCHES trial presented at the 2019 Genitourinary Cancers Symposium (ASCO GU) and published in the Journal of Clinical Oncology in July 2019, the partnership evaluated the efficacy and safety of XTANDI plus androgen deprivation therapy (ADT) versus ADT plus placebo in men with mHSPC. The primary endpoint of radiographic progression-free survival (rPFS) was met.

Additionally, the submission is supported by data from ENZAMET, an Astellas-supported, investigator-sponsored Phase 3 research study led by the Australian and New Zealand Urogenital and Prostate Cancer Trials Group (ANZUP) and sponsored by the University of Sydney. The ENZAMET trial evaluated XTANDI plus ADT versus ADT plus a standard nonsteroidal antiandrogen therapy (bicalutamide, nilutamide or flutamide) in men with mHSPC to provide an active control. The primary endpoint of overall survival (OS) was met.

Concurrently, the data from the ARCHES and ENZAMET studies have been submitted to the European Medicines Agency (EMA) and to the Pharmaceuticals and Medical Devices Agency (PMDA) in Japan to support an indication for XTANDI for mHSPC.