Durvalumab and Olaparib for the Treatment of Prostate Cancer in Men Predicted to Have a High Neoantigen Load

This phase II trial studies how well durvalumab and olaparib work in treating prostate cancer in men predicted to have specific genetic mutations (a high neoantigen load). Immunotherapy with monoclonal antibodies, such as durvalumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. PARPs are proteins that help repair DNA mutations. PARP inhibitors, such as olaparib, can keep PARP from working, so tumor cells can't repair themselves, and they may stop growing. Giving durvalumab and olaparib may kill more tumor cells in patients with prostate cancer predicted to have a high neoantigen load.