Study to Assess the Effect of 24 Weeks of Treatment With Vildagliptin in Patients With Type 2 Diabetes

A Single-center,Double-blind,Randomised,Placebo-controlled,Parallel-group Study to Assess the Effect of 24 Weeks of Treatment With Vildagliptin on Insulin Sensitivity and Its Underlying Mechanism in Patients With T2DM Treated With Metformin

The study will demonstrate the effect of 24 weeks of treatment with vildagliptin compared to placebo on insulin sensitivity in patients with type 2 diabetes mellitus (T2DM) treated with metformin, assessed as glucose Rd (rate of glucose disposal) during a hyperinsulinemic euglycemic clamp.

Inclusion Criteria:

1. Age in the range of 18-70 years.
2. Patients with T2DM, diagnosed at least 6 months prior to Visit 1, who have received metformin for at least 3 months and have been on a stable dose of at least 1000mg daily for a minimum of 4 weeks prior to Visit 1.
3. HbA1c ≤ 7.6% at Visit 1.
4. Body mass index (BMI) in the range of 22-38kg/m2 inclusive at Visit 1.

Exclusion Criteria:

1. Pregnant or nursing (lactating) women.
2. Patients with cardiac pacemakers or with metallic implants incompatible with magnetic resonance methodology.
3. Congestive heart failure requiring pharmacologic treatment. Other protocol-defined inclusion/exclusion criteria may apply.