A Randomized Phase 2b Study of ZEN003694 in Combination With Enzalutamide Versus Enzalutamide Monotherapy in Patients With Metastatic Castration-Resistant Prostate Cancer

Summary

This is an open-label, randomized, Phase 2b study of ZEN003694 in combination with enzalutamide vs. enzalutamide monotherapy in patients with mCRPC who have progressed on prior abiraterone by PCWG3 criteria. Disease must have progressed on only abiraterone by PCWG3 criteria prior to study entry. The patient population will be separated into two cohorts: Cohort A: Patients with poor response to prior abiraterone defined as: * Abiraterone started in hormone-sensitive prostate cancer (HSPC) disease setting: \< 12 months duration on abiraterone or failure to achieve PSA nadir of 0.2 ng/mL while taking abiraterone, or; * Abiraterone started in castrate-resistant prostate cancer (CRPC) disease setting: \< 6 months duration on abiraterone or failure to achieve PSA50 response while on abiraterone Cohort B: Patients with response to prior abiraterone, defined as: * Abiraterone started in hormone-sensitive prostate cancer (HSPC) disease setting: ≥ 12 months duration on abiraterone and nadir PSA \< 0.2 ng/mL, or; * Abiraterone started in castrate-resistant prostate cancer (CRPC) disease setting: ≥ 6 months duration on abiraterone and confirmed PSA50 response

Eligibility

Age range

18+ years

Sex

Male

Healthy volunteers

No

Interventions

• Drug
  ZEN003694

  72 mg PO QD

• Drug
  Enzalutamide

  160 mg PO QD

Locations (31)