A total of 2840 patients were randomized 1:1 to receive either neratinib (n=1420) or placebo (n=1420). The primary analysis demonstrated a statistically significant stratified hazard ratio of 0.66 (0.49, 0.90) with an estimated 2.3% absolute difference in invasive disease-free survival (iDFS) at two years (94.2% on the neratinib arm vs 91.9% on the placebo arm).