Medivation, Astellas begin enrollment in Phase II study of breast cancer drug

The open label, single-arm, multicenter trial will enroll 80 patients in the US, Canada and Europe to evaluate enzalutamide as a single agent against AR-positive, TNBC.

All patients in the study will be orally administered with enzalutamide 160mg dose once each day.

Medivation president and chief executive officer David Hung said, "The initiation of this Phase 2 study marks an important milestone as we expand our enzalutamide development program beyond prostate cancer to explore the clinical efficacy of enzalutamide in triple-negative breast cancer, where there is a significant unmet medical need."

The clinical benefit rate, defined as the proportion of patients with a best response of complete response, partial response or stable disease at week 16 or more is the primary endpoint of the trial.