Standard of Care +/- 177Lu-PSMA-617 In de Novo mHSPC Patients With Poor PSA Response (PEACE6-Poor Responders)

This study is testing whether adding a targeted radioactive drug called lutetium-177 PSMA-617 (also known as Pluvicto) to standard hormone therapy can improve outcomes in men newly diagnosed with advanced, hormone-sensitive prostate cancer who are not responding well to initial hormone treatment. **You may be eligible if...** - You are 18 or older and have been newly diagnosed with metastatic (spread) prostate cancer that still responds to hormone therapy - Your PSA (prostate-specific antigen) level is not dropping well enough after starting standard treatment - Your PSMA PET scan shows the cancer can be targeted with this drug - Your life expectancy is more than 6 months and general health score (ECOG) is 0–2 **You may NOT be eligible if...** - You have previously received hormone therapy for prostate cancer (except for a short window) - Your PSMA scan does not show adequate uptake - You have serious kidney, liver, or bone marrow problems - You have already received lutetium-based therapies Talk to your doctor to see if this trial is right for you.