The Phase 2 study is designed to compare MDV3100 with bicalutamide – a commonly used anti-androgen, and is expected to enroll approximately 370 patients in North America and Europe.
The primary endpoint of the trial is progression-free survival.
Astellas Pharma Global Development president Steven Ryder said this is the first of two Phase 2 trials in earlier stage disease that is being initiated to evaluate the potential benefit of MDV3100 in a broad spectrum of prostate cancer patients.
"The second of our new Phase 2 trials will study MDV3100 in an even earlier-stage population, and we expect to begin the trial in the first half of this year," Ryder said.
MDV3100 slows growth and induces cell death in bicalutamide-resistant cancers via three complementary actions – 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.