(UroToday.com) In this presentation, Dr. Daniel Petrylak discussed results from the final analysis of CheckMate 9KD Cohort A2. This single-arm study evaluated the clinical activity of nivolumab plus rucaparib in men with metastatic castration-resistant prostate cancer (mCRPC) previously untreated with chemotherapy or PARP inhibitor. Patients eligible for Cohort A2 were not candidates for or refused chemotherapy. Eligible patients received nivolumab 480 mg every 4 weeks and rucaparib 600 mg BID. The co-primary endpoints were overall response rate (ORR) and PSA response rate.