Efficacy and safety of the dipeptidyl peptidase-4 inhibitor sitagliptin compared with α-glucosidase inhibitor in Japanese patients with type 2 diabetes inadequately controlled on sulfonylurea alone (SUCCESS-2): a multicenter, randomized, open-label, non-inferiority trial

We assessed the efficacy and safety of sitagliptin compared with a-glucosidase inhibitor (alpha GI) in 120 of Japanese patients with type 2 diabetes mellitus (T2DM) inadequately controlled on stable <= 2mg/day glimepiride alone [mean hemoglobin A1c (HbA1c) 7.7%] by the randomized, active-controlled, non-inferiority trial. Patients were randomly assigned to receive additional sitagliptin or aGI for 24weeks. The primary endpoint was change in HbA1c from baseline to week 12. After 12weeks, sitagliptin reduced HbA1c by -0.44% (p< 0.001) relative to aGI. At 24 weeks, the reduction was almost identical between the groups (-0.091%, p= 0.47). Gastrointestinal disorders were more common with aGI than with sitagliptin, but only minor hypoglycaemia occurred in both groups at similar frequency. These data suggested that sitagliptin was not inferior to aGI for reduction of HbA1c in Japanese T2DM patients receiving glimepiride alone, and well tolerated with minimum risk of gastrointestinal symptoms and hypoglycaemia.