Table 1.

Coprimary endpoint results

Lapatinib + capecitabineT-DM1
n = 496n = 495
IRC-PFS (clinical cutoff date, January 14, 2012)
Number of patients with events (%)304 (61)265 (54)
  Disease progression273237
  Death3128
Number of censored patients192230
Median duration of IRC-PFS (mo; 95% CI)6.4 (95% CI, 5.7–7.1)9.6 (95% CI, 8.3–10.6)
HR (95% CI)0.65 (0.549–0.771)
P value (stratified log-rank test)<0.0001
First interim analysis OS (clinical cutoff date, January 14, 2012)
Number of patients who died, n (%)129 (26)94(19)
Number of censored patients367401
Median (mo)23.3NE
HR (95% CI)0.62 (95% CI, 0.48–0.81)
P value (stratified log-rank)0.0005
Second interim analysis OS (clinical cutoff date, July 31, 2012)
Number of patients who died, n (%)182 (37)149 (30)
Median (mo; 95% CI)25.1 (95% CI, 22.7–28.0)30.9 (95% CI, 26.8–34.3)
HR (95% CI; stratified Cox regression)0.682 (0.548–0.849)
P value (stratified log-rank)0.0006
P value (unstratified log-rank test)0.0012
O'Brien–Fleming boundary0.0037