Testing Interruption of Hormonal Medications in Patients Responding Exceptionally to Therapy for Metastatic Prostate Cancer, (A-DREAM)

Inclusion Criteria: * Histologic or clinical diagnosis of metastatic prostate cancer * Must have had evidence of metastatic disease by bone scan, or nodal or visceral lesions on computed tomography (CT) or magnetic resonance imaging (MRI) prior to starting on intense antiandrogen therapy (ADT) * Radiographic evidence of disease is not required at the time of enrollment * No metastases to liver or to brain, as these represent aggressive variant disease biology for which intermittent treatment may not be favored * Must currently be receiving intense ADT for metastatic hormone sensitive prostate cancer (mHSPC) * Testosterone suppression (TS) with luteinizing hormone releasing hormone (LHRH)-agonist or LHRH-antagonist AND * An approved secondary androgen receptor pathway inhibitor (ARPI) abiraterone, enzalutamide, or apalutamide (or darolutamide if approved for this indication) * Must have remained on testosterone suppression for metastatic disease continuously (without treatment breaks) for 540-750 days (approximately 18 to 24 months) from time of first dose of LHRH agonist or antagonist by time of registration. A period of anti-androgen treatment prior to LHRH agonist or antagonist initiation is not included in the 540 - 750 days (approximately 18 to 24 months) * Must have received treatment with ARPI for at least 360 days in total by time of A032101 registration. Treatment breaks from ARPI of up to 28 days are permitted (for example peri-procedural or for management…