However , following co-administration , apixaban AUC ( 0 , ) , AUC ( 0 , t ) and Cmax were 54 % ( geometric mean ratio 1.537 ; 90 % confidence interval ( CI ) 1.394 , 1.694 ) , 55 % ( 1.549 ; 90 % CI 1.400 , 1.713 ) and 61 % ( 1.611 ; 90 % CI 1.417 , 1.831 ) higher , respectively .