Different Doses of Olaparib Given With Radium-223 in Men With Advanced Prostate Cancer With Bone Metastasis

Inclusion Criteria: * Participants must be male aged \>= 18 years of age * Participants must have histologically or cytologically confirmed adenocarcinoma of the prostate * Participants must have castrate levels of serum testosterone \< 50 ng/dL * Participants without orchiectomy must be maintained on luteinizing hormone releasing hormone (LHRH) agonist/antagonist; participants receiving prior docetaxel abiraterone, or next generation AR antagonist (enzalutamide, apalutamide, or darolutamide) for hormone sensitive disease are permitted * Participants must have progressive disease as defined by any of the following: * Castrate resistant disease as defined by PCWG-3 criteria; participants must have a rise in PSA on two successive determination at least one week apart and PSA levels \>= 2 ng/mL (only the screening PS needs to be \>= 2 ng/mL) and serum testosterone \< 50 ng/dL * Soft tissue progression as defined by RECIST version 1.1 * Bone disease progression as defined by PCWG-3 criteria including the development of two or more new lesions on bone scan * Participants must have \>= 2 bone metastases by radiographic imaging and at least 1 lesion which has not been treated with prior radiation therapy * Participants must have tumor accessible for biopsy and be agreeable to baseline tumor biopsy; a metastatic focus is preferred but if not available and prostate is still intact prostate biopsy can be performed * Availability at the study site of formalin-fixed, paraffin-emb…