Responder rates were 28.1 % , 36.1 % ( P = 0.08 ) , and 40.7 % ( P = 0.02 ) ; 16-week seizure-free rates in a pragmatic ITT analysis were 3.3 % , 4.9 % ( P = 0.59 ) , and 11.4 % ( P = 0.008 ) , respectively .