Treatment of Prostate Cancer

This is a multicenter, randomized, controlled, phase 2 clinical trial designed to evaluate the safety and efficacy of I-131-1095 radiotherapy in combination with enzalutamide compared to enzalutamide alone in patients with prostate-specific membrane antigen (PSMA)-avid metastatic castration resistant prostate cancer (mCRPC) who have progressed on abiraterone. Patients must be chemotherapy-naive and must be ineligible or refuse to receive taxane-based chemotherapy at time of study entry. PSMA-avidity will be determined by central imaging review based on assessment of 18F-DCFPyL PET/CT imaging during screening. Eligible patients meeting the PSMA-avidity criteria will be randomized in a 2:1 ratio to receive either I-131-1095 in combination with enzalutamide (80 subjects) or enzalutamide alone (40 subjects). Patients will be followed for efficacy and safety assessments during a 12-month Randomized Treatment period. Patients will be followed for an additional year for safety and survival status. Safety data will be monitored by an independent Data Monitoring Committee and the sponsor.