Study of Olaparib Maintenance Following Cabazitaxel-Carbo in Men With AVPC

The goal of this clinical research study is to learn if olaparib, when given after treatment with cabazitaxel, carboplatin, and prednisone, can help to control aggressive variant prostate cancer (AVPC). The safety of these drugs will also be studied. This is an investigational study. Cabazitaxel and carboplatin are FDA approved and commercially available for the treatment of certain types of prostate cancer. Prednisone is FDA-approved and commercially available as a corticosteroid. Olaparib is FDA approved and commercially available for the treatment of certain types of ovarian cancer. The combination of cabazitaxel and carboplatin followed by olaparib in this study is investigational. The study doctor can describe how the study drugs are designed to work. Up to 96 participants will be enrolled on this study. All will take part at MD Anderson.