Changes in prandial glucagon levels after a 2-year treatment with vildagliptin or glimepiride in patients with type 2 diabetes inadequately controlled with metformin monotherapy

Abstract

OBJECTIVE- To determine if the dipeptidyl peptidase-4 inhibitor vildagliptin more effectively inhibits glucagon levels than the sulfonylurea glimepiride during a meal. RESEARCH DESIGNANDMETHODS- Glucagon responses to a standard meal were measured at baseline and study end point (mean 1.8 years) in a trial evaluating add-on therapy to metformin with 50 mg vildagliptin b.i.d. compared with glimepiride up to 6 mg q.d. in type 2 diabetes (baseline A1C 7.3 ± 0.6%). RESULTS- A1C and prandial glucose area under the curve (AUC)0-2 h were reduced similarly in both groups, whereas prandial insulin AUC0-2 h increased to a greater extent by glimepiride. Prandial glucagon AUC0-2 h (baseline 66.6±2.3 pmol · h-1 · l-1) decreased by 3.4±1.6 pmol · h-1 · l-1 by vildagliptin (n = 137) and increased by 3.8±1.7 pmol · h-1 · l-1 by glimepiride (n = 121). The between-group difference was 7.3±2.1 pmol · h-1 · l-1 (P < 0.001). CONCLUSIONS- Vildagliptin therapy but not glimepiride improves postprandial α-cell function, which persists for at least 2 years. © 2010 by the American Diabetes Association.