The median OS was 35.7 [ 95 % confidence interval ( CI ) 27.2-44 .2 ] months [ arm A : 35.8 ( 95 % CI 28.1-43 .6 ) , arm B : 29.0 ( 95 % CI 16.0-41 .9 ) months , HR 1.03 ( 95 % CI 0.66-1 .61 ) , P = 0.9 ] .