Aims/hypothesis: Type 2 diabetes is difficult to manage in patients with a long history of disease requiring insulin therapy. Moreover, addition of most currently available oral antidiabetic agents increases the risk of hypoglycaemia. Vildagliptin is a dipeptidyl peptidase-IV inhibitor, which improves glycaemic control by increasing pancreatic beta cell responsiveness to glucose and suppressing inappropriate glucagon secretion. This study assessed the efficacy and tolerability of vildagliptin added to insulin therapy in patients with type 2 diabetes.
Materials and methods: This was a multicentre, 24-week, double-blind, randomised, placebo-controlled, parallel-group study in patients with type 2 diabetes that was inadequately controlled (HbA(1c) = 7.5-11%) by insulin. Patients received vildagliptin (n = 144; 50 mg twice daily) or placebo (n = 152) while continuing insulin therapy.
Results: Baseline HbA(1c) averaged 8.4 +/- 0.1% in both groups. The adjusted mean change from baseline to endpoint (AMDelta) in HbA(1c) was -0.5 +/- 0.1% and -0.2 +/- 0.1% in patients receiving vildagliptin or placebo, respectively, with a significant between-treatment difference (p = 0.01). In patients aged >/=65 years, the AMDelta HbA(1c) was -0.7 +/- 0.1% in the vildagliptin group vs -0.1 +/- 0.1% in the placebo group (p < 0.001). The incidence of adverse events was similar in the vildagliptin (81.3%) and placebo (82.9%) groups. However, hypoglycaemic events were less common (p < 0.001) and less severe (p < 0.05) in patients receiving vildagliptin than in those receiving placebo.
Conclusions/interpretation: Vildagliptin decreases HbA(1c) in patients whose type 2 diabetes is poorly controlled with high doses of insulin. Addition of vildagliptin to insulin therapy is also associated with reduced confirmed and severe hypoglycaemia. ClinicalTrials.gov ID no.: NCT 00099931.
Trial registration: ClinicalTrials.gov NCT00099931.