In this double-blind , randomized , placebo-controlled trial , 51 patients with T2DM of 2.6 1.9 years ' duration and an A1C of 6.8 0.8 % ( 51 8.7 mmol/mol ) completed 4 weeks of IIT before randomization to daily subcutaneous liraglutide or placebo injection , with serial assessment of - cell function by Insulin Secretion-Sensitivity Index-2 ( ISSI-2 ) on oral glucose tolerance test performed every 12 weeks .