Background and Need: Among metastatic prostate cancers, aggressive variant types exhibit resistance to existing hormone therapies and have a significantly poorer prognosis. There is an urgent need for new treatment strategies targeting this high-risk group. M.D. Anderson Cancer Center is conducting this clinical trial to maximize therapeutic efficacy through a multi-pronged approach. ## Combination Therapy Mechanism: Cabazitaxel and carboplatin are microtubule inhibitors and DNA-damaging agents, respectively, that directly kill tumor cells. Setrelimab is a PD-1 inhibitor (immune checkpoint inhibitor) that helps immune cells recognize cancer cells. Niraparib is a DNA repair inhibitor that blocks DNA repair, promoting cancer cell death. By administering these three drugs sequentially, the strategy aims to simultaneously block multiple survival pathways of the tumor. ## Clinical Design: This study is a Phase 2 trial and is currently in the active, not recruiting phase. It started on December 29, 2020, and its primary goal is to evaluate safety and anti-cancer efficacy. The primary endpoint and the exact number of target patients have not been disclosed, but the study targets patients with aggressive variant metastatic prostate cancer. ## Differentiation from Existing Treatments: The current standard treatment consists of hormone inhibitors and a single chemotherapy regimen, which has limited efficacy against variant types. This trial attempts a multi-pronged attack by simultaneously applying chemotherapy, immunotherapy, and a DNA repair inhibitor. If successful, it could significantly improve response rates and survival compared to existing treatments. ## Market and Industry Impact: Aggressive variant prostate cancer is an area with limited treatment options, so positive results could be extended to other cancers using the same mechanism. Furthermore, the accumulation of clinical evidence for the combination of DNA repair inhibitors and immune checkpoint inhibitors will significantly impact the pipeline strategies of pharmaceutical companies.