Study Comparing Opevesostat with Other Hormonal Treatments in Advanced Prostate Cancer

Inclusion Criteria

• Have a confirmed diagnosis of prostate cancer that has spread and is resistant to standard hormone therapy.
• Show evidence of cancer spread through bone or soft tissue scans.
• Cancer must have progressed while on hormone therapy within the last 6 months.
• Previously treated with one next-generation hormonal agent for at least 8 weeks.
• Have a performance status score of 0 or 1, indicating full activity or some restriction in strenuous activities.
• Maintain low testosterone levels due to ongoing hormone therapy.
• Have adequate organ function based on medical tests.
• Provide a tumor sample from a recent biopsy.
• If positive for hepatitis B, must have undetectable viral load after treatment.
• If previously infected with hepatitis C, must have undetectable viral load.
• Must have recovered from side effects of previous cancer treatments.
• HIV-positive participants must have well-controlled HIV on treatment.

Exclusion Criteria

• Have digestive issues that affect medication absorption.
• Cannot swallow pills.
• Have a history of pituitary gland problems.
• Have poorly controlled diabetes.
• Have serious heart or blood vessel conditions.
• Have abnormal potassium or sodium levels in the blood.
• Have uncontrolled high or low blood pressure.
• Have a family history of long QT syndrome.
• Have had seizures in the past 6 months or conditions that increase seizure risk.
• Have serious heart rhythm problems.
• Have received certain chemotherapy or hormonal treatments for advanced prostate cancer.
• Have not fully recovered from major surgery.
• Have received radium treatment for prostate cancer.
• Are taking certain medications for seizures.
• Are on an unstable dose of thyroid medication.
• Have had recent radiation therapy or systemic cancer treatments.
• Are taking medications that affect liver enzymes.
• Have received recent live vaccines.
• Have used investigational drugs or devices recently.
• Have allergies to study medications.
• Have a specific type of bone scan result that complicates future assessments.
• Have another active cancer requiring treatment in the past 3 years.
• Have an immune deficiency or are on high-dose steroids.
• Have active brain metastases or cancer in the brain lining.
• Have an active autoimmune disease needing treatment in the past 2 years.
• Have an active infection needing treatment.
• Have active hepatitis B and C infections.