Prostate Cancer Clinical Trials

• Has histologically- or cytologically-confirmed adenocarcinoma of the prostate without small cell histology.

• Has prostate cancer progression while on androgen deprivation therapy (or post bilateral orchiectomy) within 6 months before Screening

• Has current evidence of distant metastatic disease (M1 disease) documented by either bone lesions on bone scan and/or soft tissue disease by computed tomography/magnetic resonance imaging (CT/MRI).

• Has disease that progressed during or after treatment with 1 novel hormonal agent (NHA)

• Has received 1 but no more than 2 taxane-based chemotherapy regimens for metastatic castration-resistant prostate cancer (mCRPC) and has had progressive disease (PD) during or after treatment

• Has ongoing androgen deprivation with serum testosterone \<50 ng/dL (\<1.7 nM)

• Has provided tumor tissue from a fresh core or excisional biopsy from soft tissue not previously irradiated

• Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 assessed within 7 days of randomization

• Has had prior treatment with PARPi or were deemed ineligible to receive treatment by the investigator or have refused PARPi treatment

• Has received prior 177Lu-PSMA-617 or were deemed ineligible to receive 177Lu-PSMA-617 treatment by the investigator or refused 177Lu-PSMA-617 treatment

• Participants who have not received cabazitaxel can be enrolled if they are ineligible for cabazitaxel treatment as determined by the investigator or have refused treatment

• If participant received first generation anti-androgen therapy before screening, the participant has evidence of disease progression \>4 weeks since the last flutamide treatment and \>6 weeks since the last bicalutamide or nilutamide treatment

• Participants receiving bone resorptive therapy (including, but not limited to, bisphosphonate or denosumab) must have been on stable doses for ≥ 4 weeks before the date of randomization

• Participants with human immunodeficiency virus (HIV) infection must have well controlled HIV on antiretroviral therapy (ART)

• Participants who are hepatitis B surface antigen (HBsAg) positive are eligible if they have received hepatitis B virus (HBV) antiviral therapy for at least 4 weeks and have undetectable HBV viral load before randomization

• Participants with history of hepatitis C virus (HCV) infection are eligible if HCV viral load is undetectable at Screening.

• Participants who can produce sperm must agree to the following during the study treatment period and for at least 7 days after the last dose of opevesostat, for at least 30 days after the last dose of abiraterone acetate, and for at least 3 months after the last dose of enzalutamide: EITHER be abstinent OR must agree to use male condom