Astellas and Medivation Announce Initiation of Phase 2 Clinical Trial of MDV3100 in Hormone-Naive Prostate Cancer Patients

Astellas Pharma Inc. and Medivation, Inc. have announced treatment of the first patient in the second new Phase 2 clinical trial of the investigational drug MDV3100, a triple-acting oral androgen receptor antagonist.

This trial is evaluating MDV3100 monotherapy as the first hormonal treatment of patients with prostate cancer.

Enrolled patients would not have had any previous hormonal therapies for the treatment of prostate cancer. This is the first trial to examine the effects of MDV3100 without a background of medical or surgical castration.

"This is the second of two Phase 2 trials that we and our partner Medivation have initiated this year to evaluate the potential benefit of MDV3100 in both advanced and earlier stage prostate cancer patients," said Steven Ryder, M.D., president, Astellas Pharma Global Development.

"Investigating MDV3100 monotherapy is the next important step to potentially providing a new option for prostate cancer patients with earlier stage disease."

The open-label, single-arm Phase 2 trial is planned to enroll approximately 60 patients in Europe. The primary endpoint of the trial is prostate-specific antigen (PSA) response. The trial will evaluate MDV3100 at a dose of 160 mg taken orally once daily for 24 weeks.