**Study Overview** This study is testing a new combination of medicines, **JSB462 (luxdegalutamide)** and **abiraterone**, to see if they help men with **metastatic hormone-sensitive prostate cancer (mHSPC)**. This type of cancer has spread from the prostate to other parts of the body but still responds to hormone therapy. The study will compare the new combination to existing treatments like abiraterone or enzalutamide, which block signals that help cancer grow. **Study Phases** 1. **Screening Period (28 days):** Doctors check if you qualify for the study. 2. **Treatment Period:** You take the study drugs daily until the cancer progresses or if you experience severe side effects. 3. **Post-Treatment Follow-Up (30 days):** Safety checks are done after stopping the treatment. **Key Points** - **Participation Length:** Includes screening, treatment, and follow-up periods. - **Treatment:** Daily oral doses of study drugs until certain conditions occur. - **Eligibility:** Must have specific cancer characteristics and not have used certain treatments before. This study helps find the best dose and checks how well the treatment works and if it's safe. Eligibility and other criteria apply.