Platform Study for Prostate Researching Translational Endpoints Correlated to Response to Inform Use of Novel Combinations

This is an open-label, non-randomized, exploratory platform protocol designed to assess the safety and antitumor activity of multiple immunotherapy combinations in participants with mCRPC who have received prior therapy. The platform study will consist of 2 stages: Stage 1, an initial stage to evaluate safety, biomarkers, and clinical activity of a combination and Stage 2, an expanded cohort, when warranted, based on the safety, clinical activity, and/or biomarker results from Stage 1. The Sponsor intends to modify and/or add new combinations to the protocol as data emerge from this and other trials. Participants must provide consent for archival tissue from a prior biopsy or surgery for prostate cancer and must consent to baseline and on-treatment biopsies, if medically feasible. Participants will be assigned to receive one of the enrolling combination study interventions and will be monitored for safety and response.