Docetaxel to Androgen Receptor Pathway Inhibitors in Patients With Metastatic Castration Sensitive Prostate Cancer and Suboptimal PSA Response

Inclusion Criteria: * Histologically/cytologically confirmed adenocarcinoma of the prostate or participants with a PSA \>100 ng/ml (100 ug/L) and radiographic evidence of metastatic disease at diagnosis. * Metastatic disease by conventional imaging (bone scan or CT and/or MRI or PSMA-PET scan at the time of ADT initiation. * PSA of ≥ 2.0 ng/ml (2.0 ug/L) prior to commencement of ADT (this refers to patients who have histologically/cytologically confirmed adenocarcinoma of the prostate) * Patients will have recovered from any treatment-related toxicities prior to enrollment (unless ≤ grade 1, irreversible, or considered by investigator as not clinically significant). * Patients may enroll with persistent toxicities attributable to ADT, including hot flushes and fatigue, of any grade, provided these toxicities are clinically stable, not rapidly worsening, and not considered by the Investigator to pose a safety risk or impair the patient's ability to comply with study procedures. Such toxicities do not need to resolve to Grade ≤1 prior to study entry. * Receipt of ADT for mCSPC for at least 6 months and no greater than 12 months (+/- 3 weeks) at time of enrollment. * Receipt of ARPI (e.g. abiraterone acetate, enzalutamide, apalutamide, or darolutamide) for at least 4 months (+/- 2 weeks) at time of enrollment * Patients may have had radiotherapy to prostatic bed and/or metastatic sites prior to enrollment. Potential trial participants should have recovered from radiotherapy-rel…