This is an investigational study. Apalutamide is not FDA approved or commercially available. It is currently being used for research purposes only. Prednisone is FDA-approved and commercially available as a corticosteroid. Ipilimumab is FDA approved to treat metastatic melanoma. Abiraterone acetate, cabazitaxel and carboplatin are FDA-approved and commercially available for the treatment of metastatic CRPC. It is considered investigational to give this combination of drugs for the treatment of metastatic CRPC.