A Phase II Study of AAA617 Alone and AAA617 in Combination With ARPI in Patients With PSMA PET Scan Positive CRPC

Key Inclusion criteria * Participants must be adults ≥ 18 years of age with signed informed consent prior to participation to study * Histologically or cytologically confirmed prostate cancer * Participants must have ongoing androgen deprivation therapy with a GnRH agonist/antagonist or prior bilateral orchiectomy at the time of randomization. Intermittent administration of ADT is accepted before randomization if criterion for serum testosterone is met * Castrate level of serum testosterone (\< 1.7 nmol/l \[50 ng/dl\]) on GnRH agonist or antagonist therapy (continuous/intermittent) or after bilateral orchiectomy prior to randomization * Participants must have evidence of PSMA-positive disease (N1 or M1) as seen on a AAA517 or piflufolastat F 18 PET/CT scan at baseline as determined by Blinded Independent Central Review (BICR) based on the methodology proposed in the Prostate Cancer Molecular Imaging Standardized Evaluation (PROMISE) (Eiber et al 2018). Participants with M1 disease only on PSMA PET scan are allowed to participate * Participants must have a negative conventional imaging for M1 disease. * Participants must have adequate organ functions: bone marrow reserve, hepatic \& renal Key Exclusion criteria * Prior or present evidence of metastatic disease as assessed by CT/MRI locally for soft tissue disease and whole-body radionuclide bone scan for bone disease. Exception: Participants with pelvic disease may be eligible (e.g., participants with enlarged lymph nodes b…