This multicenter , adaptive , double-blind , parallel-arm study randomized patients ( N = 1,098 ; mean baseline age 54 years ; HbA1c 8.1 % [ 65 mmol/mol ] ; weight 86.4 kg ; diabetes duration 7 years ) to dulaglutide 1.5 mg , dulaglutide 0.75 mg , sitagliptin 100 mg , or placebo ( placebo-controlled period up to 26 weeks ) .