Safety, Pharmacokinetics, and Preliminary Efficacy of VIR-5500 (AMX-500) in Prostate Cancer

This study tests a new drug called VIR-5500 (also known as AMX-500) in men with advanced prostate cancer that has spread to other parts of the body and is no longer responding to standard hormone treatments. **You may be eligible if...** - You have prostate cancer that has spread (metastatic) and is no longer responding to hormone-lowering treatments (called castration-resistant prostate cancer or mCRPC) - You have already tried at least one hormone-blocking drug (such as enzalutamide, abiraterone, apalutamide, or darolutamide) - You have already received at least one chemotherapy regimen using drugs like docetaxel or cabazitaxel - Your doctor has determined that standard treatments are no longer suitable for you - Some parts of the study also require prior treatment with a radioactive PSMA-targeted therapy (such as lutetium-177 PSMA) **You may NOT be eligible if...** - You have not yet tried standard second-line hormone therapies or taxane-based chemotherapy - Your cancer has not been confirmed to be progressing Talk to your doctor to see if this trial is right for you.