A Phase 1b/2 Study of CPI-1205, a Small Molecule Inhibitor of EZH2, Combined With Enzalutamide or Abiraterone/Prednisone in Patients With Metastatic Castration Resistant Prostate Cancer

Condition: Metastatic Castration Resistant Prostate Cancer (mCRPC)

Study Type: Interventional

Clinical Trials Identifier NCT 8-digits: NCT03480646

Sponsor: Constellation Pharmaceuticals

Phase: Phase 1/Phase 2


  • Age: minimum 18 Years maximum N/A
  • Gender: Male

Inclusion Criteria:

  • Adults (Age ≥ 18 years)
  • Eastern Cooperative Oncology Group (ECOG) performance status 0-1
  • Life expectancy of at least 12 weeks
  • Histologically or cytologically confirmed adenocarcinoma of the prostate
  • Progressive disease in the setting of medical or surgical castration (i.e. CRPC)
  • Documented metastatic disease
  • Must have undergone bilateral orchiectomy (surgical castration) or be willing to continue gonadotropin-releasing hormone (GnRH) analog or antagonist (medical castration)
  • Serum testosterone <50 ng/dL
  • Receipt of prior line of second generation androgen inhibitor
  • Demonstrate adequate organ function as defined below:
  • Absolute Neutrophil Count (ANC) ≥ 1,000/μL
  • Platelet Count ≥ 100,000/μL
  • Hemoglobin (Hgb) ≥ 8 g/dL
  • Serum creatinine ≤ 2 × upper limit of normal (ULN) OR
  • Creatinine clearance (CrCl) ≥ 40 mL/min as estimated by the Cockcroft and Gault formula1 in subjects with creatinine > 2 X ULN
  • Bilirubin ≤ 1.5 × ULN unless evidence of Gilbert's disease in which case < 3 x ULN
  • Aspartate aminotransferase (AST) ≤ 2.5 × ULN without liver metastases; must be ≤ 5 × ULN with liver metastases
  • Alanine aminotransferase (ALT) ≤ 2.5 × ULN without liver metastases; must be ≤ 5 × ULN with liver metastases

Exclusion Criteria:

  • Known symptomatic brain metastases (NOTE: patients with treated epidural disease are allowed)
  • Treatment with any of the following for prostate cancer within the indicated timeframe prior to day 1 of treatment: 1. First generation: AR antagonists (e.g., bicalutamide, nilutamide, flutamide) within 4 weeks 2. 5 alpha reductase inhibitors, ketoconazole, estrogens (including diethylstilbesterol [DES]), or progesterones within 2 weeks 3. Chemotherapy within 3 weeks 4. Biologic therapy within 4 weeks 5. Investigational therapy within 3 weeks (or within a time interval less than at least 5 half-lives of the investigational agent [if known], whichever is longer). 6. Immunotherapy within 4 weeks 7. Prior radionuclide therapy within 4 weeks

View trial on ClinicalTrials.gov