In PREVAIL, pts with progressive mCRPC following ADT had significantly improved radiographic progression-free survival (rPFS) and overall survival (OS) on ENZ vs PL (Beer TM et al, N Engl J MED, 2014). In the current study, the efficacy and safety of ENZ vs PL were evaluated in a similar patient population in China, Taiwan, Hong Kong and South Korea.
Pts with asymptomatic/mildly symptomatic progressive mCRPC following ADT were randomised 1:1 to ENZ (160 mg/day) or PL. The primary endpoint was time to prostate-specific antigen (PSA) progression (time from randomisation to PSA progression or death). The secondary endpoints were OS (time from randomisation to death) and rPFS (time from randomisation to radiographic progression). An interim analysis was planned following 169 PSA progression events. The unstratified Cox proportional hazards model (covariate = treatment group) and log-rank test (2-sided significance level = 0.011, primary; 0.05, secondary) were used. Safety was assessed by recording adverse events (AE).
409 pts from 49 centres were randomised (209 ENZ, 200 PL). Baseline characteristics were balanced between treatment groups. 169 PSA progression events occurred. Median time to PSA progression was 7.5 months in the ENZ arm vs 2.9 for PL (HR 0.36; 95% CI 0.27, 0.50; p
ENZ showed significantly improved time to PSA progression over PL and was generally well tolerated. The trial was stopped as it had reached its primary objective.
Clinical trial identification
ClinicalTrials.gov NCT02294461; First received: November 13, 2014; Last updated: November 25, 2015
Legal entity responsible for the study
Astellas Pharma, Inc.
Astellas Pharma, Inc. and Medivation, Inc.
Y-S. Pu: The author discloses that they received funding from Astellas Pharma Inc. for clinical studies.
S. Yamada, S. Noda: The author declares that they own stocks in, and are an employee of, Astellas Pharma Inc.
All other authors have declared no conflicts of interest.