Inclusion criteria: The main inclusion criteria include, but are not limited to, the following: * Confirmed histological or cytological diagnosis of prostate adenocarcinoma without small cell histology. * Progression of prostate cancer and having received androgen deprivation therapy (ADT) or having undergone bilateral orchiectomy in the 6 months prior to selection. * Evidence of disease progression from >4 weeks since last flutamide treatment or >6 weeks since last bicalutamide or nilutamide treatment, if receiving first-generation antiandrogen therapy as last-line treatment. * Current evidence of metastatic disease. * Prior treatment with 1 or 2 novel hormonal agents (NHA) for non-metastatic or metastatic hormone-sensitive prostate cancer or castration-resistant prostate cancer and having experienced disease progression during or after treatment. * Treatment with bone resorption therapy (including, but not limited to, bisphosphonates or denosumab) must have been at stable doses for >4 weeks prior to randomization. * Participants who experienced adverse events (AEs) due to previous cancer therapies must have recovered to * Participants infected with the human immunodeficiency virus (HIV) must have their HIV well controlled with antiretroviral therapy. * Participants who are positive for hepatitis B surface antigen (HBsAg) are eligible if they have received antiviral therapy for hepatitis B virus (HBV) for at least 4 weeks and have an undetectable HBV viral load. * Participants with a history of hepatitis C virus (HCV) infection are eligible if their HCV viral load is undetectable. Exclusion criteria: The main exclusion criteria include, but are not limited to, the following: * History of pituitary dysfunction. * Poorly controlled diabetes mellitus. * Active or unstable cardiovascular/cerebrovascular disease, including thromboembolic events and a history of stroke or transient ischemic attack within 6 months prior to the first dose of the study intervention, a history of myocardial infarction within 6 months prior to the first dose of the study intervention, New York Heart Association class III or IV congestive heart disease or heart failure, symptomatic coronary artery disease, or unstable angina. * History or family history of long corrected QT interval (QTc) syndrome. * Myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) or features suggestive of MDS/AML. * History or current condition of adrenal insufficiency. * History of (non-infectious) pneumonitis requiring steroids or current pneumonitis. * HIV-infected participants with a history of Kaposi's sarcoma and/or multicentric Castleman disease. * He underwent major surgery, including local prostate intervention (except prostate biopsy), within 28 days prior to randomization and did not recover from toxicities or complications. * Received an unstable dose of thyroid hormone therapy within 6 months prior to the first dose of the study intervention.* Received a whole blood transfusion in the last 120 days before randomization (transfusions of packed red blood cells and platelets are acceptable if they were not given within 28 days prior to randomization). * Received prior systemic cancer therapy, including investigational agents, within 4 weeks prior to randomization. * Received prior radiotherapy within 2 weeks of the start of the study intervention or radiation-related toxicities that required corticosteroids. * Received a live or live attenuated vaccine within 30 days prior to the first dose of the study intervention. The administration of inactivated vaccines is permitted. * Diagnosed with immunodeficiency or receiving chronic systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of the study intervention. * Additional known malignant neoplasm that is progressing or has required active treatment in the past 3 years. * Known active metastases in the central nervous system (CNS) and/or carcinomatous meningitis. * Active autoimmune disease that has required systemic treatment in the last 2 years. * Active infection requiring systemic therapy. * Concurrent active HBV or HCV infections.