Cabazitaxel, Carboplatin, and Cetrelimab Followed by Niraparib With or Without Cetrelimab for the Treatment of Aggressive Variant Metastatic Prostate Cancer

This phase II trial studies the effect of cabazitaxel, carboplatin, and cetrelimab followed by niraparib with or without cetrelimab in treating patients with aggressive variant prostate cancer that has spread to other places in the body (metastatic). Chemotherapy drugs, such as cabazitaxel and carboplatin, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. PARPs are proteins that help repair DNA mutations. PARP inhibitors, such as niraparib, can keep PARP from working, so tumor cells can't repair themselves, and they may stop growing. Immunotherapy with monoclonal antibodies, such as cetrelimab, may help the body's immune system attack the tumor, and may interfere with the ability of tumor cells to grow and spread. Giving niraparib with or without cetrelimab, after treatment with cabazitaxel, carboplatin, and cetrelimab, may help control aggressive variant prostate cancer.