Atascadero

Researchers are evaluating whether combining the investigational drug mevrometostat (PF-06821497) with enzalutamide works better than enzalutamide alone in men with metastatic castration-sensitive prostate cancer (mCSPC) who have not previously received androgen receptor pathway inhibitors or chemotherapy in this setting. This Phase 3, randomized, double-blind, placebo-controlled study involves participants who have only received limited prior androgen-deprivation therapy and no evidence of disease progression before starting the study. Participants will be randomly assigned to one of two groups: one group receives oral mevrometostat together with oral enzalutamide continuously, while the other group receives a placebo with oral enzalutamide continuously. The study includes a Screening Phase, a Treatment Phase after randomization, followed by Safety Follow-up and Long-Term Follow-up periods to monitor outcomes and side effects. Throughout the study, participants will undergo regular assessments including imaging scans to evaluate disease progression, laboratory tests, and monitoring of symptoms and adverse events. The main outcome measured is Radiographic Progression Free Survival (rPFS) over approximately 4 years from randomization. Safety and long-term effects will also be monitored to understand how well participants tolerate the treatments and how the disease responds over time.