Tokyo, Japan and San Francisco, CA – May 24, 2013 – Astellas Pharma Inc. (TSE: 4503) and Medivation, Inc. (NASDAQ: MDVN) today announced that Astellas has submitted an application for marketing approval of enzalutamide (generic name) to the Ministry of Health, Labour and Welfare in Japan for the treatment of prostate cancer.

Enzalutamide is a novel, once-daily, oral androgen receptor signaling inhibitor. It inhibits multiple steps in the androgen receptor signaling pathway, which has been shown to decrease cancer cell growth and can induce cancer cell death (apoptosis).

This filing application is based mainly on results obtained from the global Phase 3 trial (the AFFIRM trial)* and a Phase 1-2 trial conducted in Japan** .

* A multi-country, double-blind, placebo-controlled study in patients with advanced castration-resistant prostate cancer who had previously undergone docetaxel-based chemotherapy.

** An open-label, study. Phase 1 enrolled patients with advanced castration-resistant prostate cancer and Phase 2 enrolled patients with advanced castration-resistant prostate cancer who had received docetaxel therapy.