The IRC analysis demonstrated a statistically significant increase in PFS ( hazard ratio [ HR ] = 0.451 ; 95 % confidence interval [ CI ] = 0.351 to 0.580 , p < 0.0001 ) consistent with the benefit reported by investigators ( HR = 0.484 ; 95 % CI = 0.388 to 0.605 , p < 0.0001 ) .