At 24 weeks , greater improvements in adjusted mean change from baseline HbA1c ( difference vs placebo [ 95 % CI ] , -0.33 % [ -0.50 % , -0.17 % ] , [ -4 ( -5.5 , -1.9 ) mmol/mol ] , P < 0.0001 ) , FPG ( -0.41 [ -0.78 , -0.03 ] mmol/L , P = 0.03 ) , PPG AUC0-180 ( -168 [ -245 , -91.8 ] mmol min/L , P < 0.0001 ) , C-peptide AUC0-180 ( 19.7 [ 5.2 , 34.2 ] nmol min/L , P = 0.008 ) , insulinogenic index ( 0.06 % [ 0.02 % , 0.09 % ] , P = 0.002 ) , and greater suppression of glucagon secretion ( glucagon AUC0-180 , -322 [ -493.6 , -150.7 ] pmol min/L , P = 0.0003 ) were observed with saxagliptin versus placebo .