Results: Of the 409 randomized pts from China, Korea, Taiwan, and Hong Kong (ENZ 209; PL 200), 84 were from Taiwan (ENZ 42; PL 42). Baseline characteristics were generally balanced among treatment groups, except median baseline PSA (ENZ 25.3 µg/L [range 3.0–461.2]; PL 59.8 µg/L [range 2.4–1383.0]). Median TTPP was 10.2 months for ENZ vs 2.9 for PL (HR 0.44; 95% CI 0.24, 0.82; p=0.0059). Due to the small number of deaths (ENZ 2; PL 6), median OS was not yet reached (NYR) in either treatment group (HR 0.25; 95% CI 0.05, 1.22; p=0.0633). Median rPFS was NYR for ENZ and was 11.3 months for PL (HR 0.29; 95% CI 0.12, 0.71; p=0.0040). Median time on treatment was 7.9 months for ENZ and 4.1 months for PL. Although slightly more ENZ than PL pts reported ≥1 AE (83.3% vs 78.6%), fewer ENZ than PL pts reported ≥1 serious AE (19.0% vs 35.7%), AEs ≥ grade 3 (28.6% vs 40.5%), and AEs leading to treatment discontinuation (14.3% vs 19.0%). No seizures or convulsions were reported in either group.

 

Conclusion: The results of this subgroup analysis demonstrate that the effect of ENZ vs PL on the efficacy and safety of TW pts was consistent with that observed in the entire pt population.