Study of Cabozantinib and Nivolumab in Metastatic Castration Resistant Prostate Cancer

Eligible subjects will undergo a baseline biopsy prior to treatment initiation. They will then initiate treatment with cabozantinib (40 mg orally daily) and nivolumab (480 mg intravenously every four weeks). An on-treatment biopsy will be performed during Cycle 2. Subjects will continue treatment until radiographic progression, toxicity or withdrawal. Prostate-specific antigen (PSA) levels will be evaluated once every cycle. Radiographic assessments will occur every two cycles for one year and then every three cycles thereafter. Cycle length is 28 days.