Dose-ranging efficacy of sitagliptin, a dipeptidyl peptidase-4 inhibitor, in Japanese patients with type 2 diabetes mellitus

Abstract

Sitagliptin is an oral, potent, highly selective, once-daily DPP-4 inhibitor indicated for the treatment of type 2 diabetes mellitus (T2DM). To assess the dose-ranging efficacy and safety/tolerability profile of once-daily sitagliptin 25, 50, 100, and 200 mg in Japanese patients with T2DM. In this randomized, double-blind, placebo-controlled study, 363 Japanese patients with inadequate glycemic control (HbA_1c=6.5-10%; FPG≤270 mg/dL) were randomized (1:1:1:1:1) to placebo, sitagliptin 25, 50, 100, or 200 mg q.d. for 12 weeks. The primary endpoint was change from baseline in HbA_1c at Week 12. At Week 12, treatment with sitagliptin at all doses tested provided significant (p<0.001) reductions in HbA_1c (-0.69 to -1.04%) from baseline (7.49 to 7.65%) relative to placebo. Sitagliptin significantly (p<0.001) reduced fasting plasma glucose (FPG; -15.9 to -23.2 mg/dL) and 2-hour postprandial glucose (2-hr PPG; -40.3 to -65.0 mg/dL) relative to placebo, in a dose-dependent manner. At doses ≥50 mg, differences in HbA_1c, FPG, and 2-hr PPG between the sitagliptin groups were not statistically significant. Sitagliptin was generally well tolerated with a low and similar incidence of hypoglycemia and minimal weight gain relative to placebo. Treatment with sitagliptin for 12 weeks provided significant and clinically meaningful reductions in HbA_1c, FPG, and 2-hr PPG across the dose range studied and was generally well tolerated in Japanese patients with T2DM.