This study focuses on a new medicine called ifinatamab deruxtecan (or I-DXd), which aims to help people with a type of prostate cancer known as metastatic castration-resistant prostate cancer (mCRPC). The researchers want to see if I-DXd can help patients live longer and prevent the cancer from growing or spreading compared to traditional chemotherapy. **Metastatic** means the cancer has spread to other parts of the body, and **castration-resistant** means it doesn’t respond to treatments that lower testosterone.

**Key Points:**

• The study involves people with certain types of prostate cancer who have tried other treatments but need more help.
• Participants must be able to swallow pills and should not have severe lung or heart problems.
• This study may involve multiple visits and tests to monitor progress.

The study is not suitable for those who have had issues with certain lung diseases or who have been treated with similar medicines in the past. Participants need to provide a sample of their tumor for the study.