Vildagliptin is a potent and selective dipeptidyl peptidase-4 (DPP-4) inhibitor, shown to increase the active glucagon-like peptide 1 (GLP-1) levels by approximately 2- to 3-fold, and significantly reduces both fasting and postprandial glucose levels in patients with type 2 diabetes mellitus (T2DM). Vildagliptin is rapidly and well absorbed with good bioavailability (85%). The primary elimination route is hydrolysis by multiple organs. Vildagliptin has a low potential for drug interactions, as the involvement of cytochrome P450 enzymes is minimal (<1.6%) in the overall metabolism. Clinical pharmacokinetic (PK) studies have reported that vildagliptin does not affect the PK of metformin, pioglitazone, glyburide, amlodipine, valsartan, and simvastatin. In the elderly patients, vildagliptin exposure increases by 30%, which is not considered to be clinically relevant. Vildagliptin has been established to be an effective and safe therapy in elderly patients with T2DM without dose adjustment. Although vildagliptin exposure increases by approximately 2-fold in patients with renal impairment, the increase in the exposure does not correlate with the severity of renal impairment, which may be attributable to the fact that the kidneys contribute to both the excretion and the metabolism of vildagliptin. Hepatic impairment as well as gender, body mass index (BMI), and ethnicity do not affect the PK of vildagliptin. These results suggest that vildagliptin can be safely used in a diverse patients group. Vildagliptin has been shown to improve beta-cell function and enhance the sensitivity of alpha cell responsiveness to both suppressive effects of hyperglycemia and stimulatory effects of hypoglycemia in patients with T2DM. Long-term randomized clinical trials have shown that vildagliptin 50 mg once or twice daily is effective, safe, and well tolerated as either monotherapy or combination with other anti-diabetic medications in patients with T2DM.