— A New Trial Marks Expanded Phase 3 Development of MDV3100 into Earlier-Stage Disease —

Medivation, Inc. and Astellas Pharma Inc. today announced the launch of a second Phase 3 clinical trial of their investigational drug MDV3100.  This trial marks the expansion of the Phase 3 development of their novel, triple-acting oral androgen receptor antagonist into an earlier-stage patient population of men with advanced prostate cancer.

Known as PREVAIL, the trial will evaluate MDV3100 in men with advanced prostate cancer who have not yet received chemotherapy (docetaxel).   “Because patients with both early and advanced prostate cancer are in need of new treatment options, our goal is to develop MDV3100 for the broadest possible spectrum of disease states,” said David Hung, MD, president and chief executive officer of Medivation. “The initiation of the PREVAIL trial marks our expansion of Phase 3 development of MDV3100 into men with advanced prostate cancer who have not yet received chemotherapy.  The PREVAIL trial complements our ongoing Phase 3 AFFIRM trial, which is studying men with advanced prostate cancer who have previously failed chemotherapy.  We remain on track to complete enrollment in the AFFIRM trial by the end of this year.”

Steve Ryder, MD, president, Astellas Pharma Global Development said, “We are pleased to expand the MDV3100 program to evaluate the potential benefit of this promising developmental drug candidate given its unique mechanism and differentiating attributes….We believe that MDV3100 has the potential to establish a new treatment approach for prostate cancer and we look forward to initiating further trials evaluating this exciting new agent.”

PREVAIL is a randomized, double-blind, placebo-controlled, multi-national Phase 3 trial which is expected to enroll approximately 1,700 patients at sites in the United States, Canada, Europe, Australia and Israel.

Subjects of the PREVAIL trial will be men with metastatic prostate cancer who are progressing despite treatment with androgen deprivation therapy (castrate resistant).  The co-primary endpoints of the trial are overall survival and progression-free survival; secondary endpoints include time to first skeletal-related event and time to initiation of cytotoxic chemotherapy.

The trial will evaluate MDV3100 at a dose of 160 mg taken orally once daily plus standard of care versus placebo plus standard of care.  Information about patient eligibility and enrollment can be obtained by calling the PREVAIL study hotline toll-free at 1-888-243-4363.

The Phase 3 AFFIRM trial of MDV3100 in advanced prostate cancer patients who have previously failed chemotherapy is ongoing, and remains on track to complete enrollment by the end of 2010.  This randomized, double-blind, placebo-controlled trial is evaluating 160 mg/day of MDV3100 plus standard of care versus placebo plus standard of care and its primary endpoint is overall survival.  Secondary endpoints include progression-free survival, safety and tolerability. The AFFIRM study is being conducted at sites in the United States, Canada, Europe, Australia, South America and South Africa.

Positive results from the earlier Phase 1-2 trial, which is still on-going,  were published in 2010 in The Lancet.

About MDV3100

MDV3100 is an investigational therapy in clinical development for advanced prostate cancer. The novel, triple-acting, oral androgen receptor antagonist has been shown in preclinical studies to provide more complete suppression of the androgen receptor pathway than bicalutamide (casodex), the most commonly used anti-androgen.

MDV3100 slows growth and induces cell death in bicalutamide-resistant cancers via three complementary actions – MDV3100 blocks testosterone binding to the androgen receptor, impedes movement of the androgen receptor to the nucleus of prostate cancer cells (nuclear translocation), and inhibits binding to DNA. Preclinical data published in Science in April 2009 indicated that MDV3100 is superior to bicalutamide in each of these three actions.

Joel T Nowak, M.A., M.S.W.