The purpose of this study is to see if the drug, CPI-1205, in combination with standard of care treatments enzalutamide or abiraterone/prednisone can improve conditions for males with metastatic castration resistant prostate cancer. The study is designed to determine the best dose for CPI-1205.

Inclusion Criteria:

• Adults (Age ≥ 18 years)
• Metastatic prostate cancer
• Must have undergone surgical or medical castration
• Progressive disease in the setting of medical or surgical castration (i.e. CRPC) as defined by elevated PSA AND/OR progression based on bone scan or CT scan
• Serum testosterone <50 ng/dL
• Prior hormonal treatment for metastatic disease
• Demonstrate adequate organ function

Exclusion Criteria:

• Known symptomatic brain metastases
• Clinically significant cardiovascular disease
• Active viral hepatitis or chronic liver disease
• GI disorder that negatively affects absorption
• Any other ongoing severe and/or uncontrolled medical condition