The purpose of this study is to assess the efficacy and safety of the combination of the polyadenosine 5′-diphosphoribose poly(ADP-ribose) polymerase (PARP) inhibitor olaparib and pembrolizumab in the treatment of participants with mCRPC who have failed to respond to either abiraterone acetate or enzalutamide (but not both) and to chemotherapy.
The primary study hypotheses are that the combination of pembrolizumab plus olaparib is superior to abiraterone acetate or enzalutamide with respect to:
Overall Survival (OS) and
Radiographic progression-free survival (rPFS) per Prostate Cancer Working Group (PCWG)-modified Response Evaluation Criteria in Solid Tumors Version 1.1 as assessed by blinded independent central review (BICR)