Please note this study is not being conducted in the United States. The purpose of this study is to test the hypothesis that acute DPP-4 inhibition with vildagliptin improves fat and muscle metabolism in patients with type 2 diabetes mellitus.

Inclusion Criteria:

• Must be able to complete a 3-week wash-out of current anti-diabetic medication
• Cannot take any medications which may alter gastric motility except for cardiac medication at a stable dose
• Must discontinue beta-blockers and lipid lowering drugs
• Blood glucose criteria must be met
• BMI in the range 30-35

Exclusion Criteria:

• History of type 1 diabetes, diabetes resulting from pancreatic injury, or secondary forms of diabetes
• Need for insulin within 3 months or patients on thiazolidinediones
• Patients taking a sulfonylurea or metformin who cannot safely discontinue medication for the duration of the study
• Significant concomitant disease or complications of diabetes
• Patients with any history of gastrointestinal surgery or positive gastrointestinal symptons
• High tryglycerides as defined by the protocol
• Smokers who cannot abstain from smoking during the treatment periods