Vildagliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor that is being 
evaluated in the treatment of patients with type 2 diabetes mellitus. It 
improves glycaemic control by inhibiting DPP-4 from inactivating the incretin 
hormones glucagon-like peptide-1 and glucose-dependent insulinotropic 
polypeptide, prolonging incretin activity in response to ingestion of nutrients. 
This allows for increased insulin sensitivity, decreased glucagon secretion and 
improved beta-cell function in a glucose-dependent manner. Glycaemic control 
with vildagliptin 50 or 100 mg/day, measured by a change from baseline in mean 
glycosylated haemoglobin (HbA(1c)) at study endpoint, was improved relative to 
placebo in several well designed clinical trials of vildagliptin monotherapy in 
patients with type 2 diabetes. In randomised active comparator studies, 
noninferiority of vildagliptin in reducing HbA(1c) levels from baseline was 
established to rosiglitazone, but not to metformin. Vildagliptin also showed 
efficacy in reducing HbA(1c) levels in patients with type 2 diabetes when used 
in combination with metformin, pioglitazone or insulin. Vildagliptin was 
generally well tolerated when administered alone or in combination with 
additional antidiabetic treatment. Gastrointestinal adverse events were mild to 
moderate in intensity, and occurred less frequently than with metformin. 
Hypoglycaemic events were rare and occurred at a similar incidence to that with 
placebo.