Randomized Phase II Study of ADT + Abiraterone vs ADT + Docetaxel + Abiraterone

This is a phase II, randomized, open label study comparing first line therapy with AThis is a phase II, randomized, open label study comparing first line therapy with ADT + abiraterone (doublet arm) or ADT + abiraterone + docetaxel (triplet arm) in low volume, metastatic hormone sensitive prostate cancer (mHSPC). This is a phase II, randomized, open label study comparing first line therapy with Androgen Deprivation Therapy (ADT) + abiraterone (doublet arm) or ADT + abiraterone + docetaxel (triplet arm) in low volume, metastatic hormone sensitive prostate cancer (mHSPC). The hypothesis being asked in this trial is whether first line treatment with ADT plus an androgen receptor pathway inhibitor (abiraterone) as a doublet regimen compared to ADT plus an androgen receptor pathway inhibitor (abiraterone) and docetaxel, as a triplet regimen results in superior outcomes for patients with low volume mHSPC. We plan to enroll patients with mHPSC that meet the CHAARTED criteria for low disease volume. Patients will be randomized 1:1 to either treatment arm: * doublet arm: abiraterone +ADT or * triplet arm: abiraterone + ADT + docetaxel. All subjects must receive ADT of the Investigator\'s choice (LHRH agonist/antagonists or orchiectomy) as standard therapy, started = 12 weeks before randomization.