Vildagliptin inhibits dipeptidyl peptidase IV (DPP-IV) enzymes resulting in prolonged active incretion levels. Incretin hormones [eg, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP)] regulate glucose homeostasis by increasing insulin synthesis and release from pancreatic beta cells and decreasing glucagon secretion from pancreatic alpha cells. Decreased glucagon secretion results in decreased hepatic glucose production. Under normal physiologic circumstances, incretin hormones are released by the intestine throughout the day and levels are increased in response to a meal; incretin hormones are rapidly inactivated by DPP-IV enzymes.