Study Comparing Talazoparib and Enzalutamide Combination Therapy to Enzalutamide Alone in Advanced Prostate Cancer

Inclusion Criteria

• Diagnosed with prostate cancer that has spread and is resistant to hormone therapy.
• Have mild or no symptoms from the cancer.
• Must have a specific genetic mutation (for Part 2 only).
• Agree to provide a saliva sample for genetic testing (optional for Part 1).
• Must have low testosterone levels due to medical or surgical treatment.
• Cancer must be visible on scans in bones or soft tissues.
• Cancer must be progressing despite hormone therapy, shown by rising PSA levels, new bone lesions, or growth of soft tissue tumors.
• May be using bone-strengthening medications like bisphosphonates or denosumab.
• Must be in good general health with a performance status of 0 or 1.
• Expected to live at least 12 more months.
• Able to swallow pills and have no known allergies to the study drugs.
• Must agree to use condoms and for female partners to use additional contraception during and after the study.
• Must not donate sperm during and for 4 months after the study.
• Must provide informed consent and be willing to follow study procedures.

Exclusion Criteria

• Have received certain cancer treatments for prostate cancer before.
• Only have cancer spread to lymph nodes below the aorta.
• Have used specific prostate cancer drugs like enzalutamide or PARP inhibitors before.
• Have had recent chemotherapy or other cancer treatments.
• Have used investigational drugs recently.
• Have taken opioids for cancer pain recently.
• Are using certain medications that affect drug absorption.
• Have had major surgery or radiation therapy recently.
• Have significant heart or kidney problems.
• Have liver problems or abnormal blood counts.
• Have brain metastases or certain spinal conditions.
• Have a history of certain blood disorders or other cancers.
• Have digestive issues affecting drug absorption.
• Are not willing to use contraception as required.
• Are involved in the study's conduct or are related to someone who is.
• Have other medical or psychiatric conditions that could interfere with the study.
• Have a history of seizures or conditions that increase seizure risk.