A Study of GSK5458514 Administered Alone or In Combination With Other Anti-Cancer Agents in Participants With Prostate Cancer

This study is testing a new drug called GSK5458514, either on its own or combined with other cancer treatments, in men with advanced prostate cancer that has stopped responding to hormone therapy. **You may be eligible if...** - You are male, 18 or older - You have metastatic prostate cancer that no longer responds to hormone therapy (called castration-resistant prostate cancer) - Your cancer has progressed after treatment with newer hormone-blocking drugs and 1–2 rounds of chemotherapy - You are willing to use contraception during the study and for about 6 months after **You may NOT be eligible if...** - You have not received prior treatment with certain hormone-blocking drugs or chemotherapy - You only have rising PSA levels with no visible cancer on scans Talk to your doctor to see if this trial is right for you.