The purpose of this study is to assess the safety and effectiveness of three doses of vildagliptin, an unapproved drug, compared to placebo in lowering overall blood glucose levels in people with type 2 diabetes who have not been previously treated with drug therapy to lower their blood sugar.

Inclusion Criteria:

• Body mass index (BMI) in the range 22-45
• Blood glucose criteria must be met
• Not currently on drug therapy for type 2 diabetes

Exclusion Criteria:

• Type 1 diabetes
• Evidence of serious diabetic complications
• Evidence of serious cardiovascular conditions
• Laboratory value abnormalities as defined by the protocol
• Other protocol-defined exclusion criteria may apply