- Patients with diabetes mellitus type 2 diagnosis as defined by a previous diagnosis of DM and current therapy with antidiabetic agents, or by fulfillment of 1997 American Diabetic Association (ADA) criteria, may be included if they fulfill the following criteria: (i) therapeutic regimen limited to specific oral agents including sulfonylureas (e.g. glipizide and glyburide) and/or biguanides (e.g. metformin); (ii) stable therapeutic regimen as defined by no changes in oral agents for at least 3 months; (iii) Hemoglobin A1C (HgbA1C) < 8.5 %.