Study of Sipuleucel-T With or Without Continuing New Hormonal Agents in Metastatic Prostate Cancer

This study is testing whether the immune therapy sipuleucel-T (Provenge), combined with or without continuing hormone-suppressing drugs (called new hormonal agents or NHAs), is effective for men with metastatic prostate cancer whose PSA is rising while on hormone therapy but whose cancer has not yet progressed on scans. **You may be eligible if...** - You are 18 or older - You have metastatic prostate cancer confirmed by biopsy - You are currently on combined hormone therapy (LHRH analog + enzalutamide, apalutamide, or abiraterone) and your PSA level is rising, but imaging does not show cancer progression - You have a good health status (ECOG 0 or 1) and adequate blood counts and organ function **You may NOT be eligible if...** - Your prostate cancer has progressed on imaging scans - You are not currently on a new hormonal agent (NHA) therapy - You have had another active cancer in the past 3 years (with some exceptions) - Your organ function or blood counts are below the required levels Talk to your doctor to see if this trial is right for you.