Study on ZEN003694 and Enzalutamide Compared to Enzalutamide Alone in Treating Advanced Prostate Cancer

Inclusion Criteria

• Men aged 18 years or older.
• Have advanced prostate cancer that has spread and is resistant to hormone therapy.
• Have been on hormone therapy for at least 8 weeks before the study, with low testosterone levels.
• Cancer must have progressed after abiraterone treatment.
• Not suitable for chemotherapy or have chosen not to undergo chemotherapy.
• For Cohort A: Poor response to abiraterone, defined as less than 12 months on abiraterone in hormone-sensitive prostate cancer or less than 6 months in castration-resistant prostate cancer, or not achieving specific PSA levels.
• For Cohort B: Good response to abiraterone, defined as 12 months or more on abiraterone in hormone-sensitive prostate cancer or 6 months or more in castration-resistant prostate cancer, with specific PSA levels achieved.
• Good overall health with an ECOG performance status of 0 or 1.

Exclusion Criteria

• History of brain cancer spread, seizures, or conditions that increase seizure risk.
• Previous treatment with a BET inhibitor or participation in a study involving ZEN003694.
• Previous use of second-generation androgen receptor inhibitors like enzalutamide.
• Prior chemotherapy for advanced prostate cancer, unless it was given in the hormone-sensitive stage and completed at least 6 months before the study.
• Recent use of other cancer treatments within 2 weeks before starting the study.
• Use of testosterone therapy after stopping abiraterone.
• Not fully recovered from side effects of previous cancer treatments, except for hair loss and nerve damage.
• Recent radiation therapy within 2 weeks before starting the study.