- Part B: A subject will be eligible for inclusion in Part B of this study only if all of the following criteria are met: Subjects with documented type 2 diabetes mellitus diagnosis (diagnosed not less than 6 months; HbA1c less than or equal to 10 % and FPG < 280 mg/dL at screening) who are either controlled by diet alone or monotherapy for a minimum of 3 months with either oral sulfonylureas, rosiglitazone, metformin, or acarbose. They must be willing/able to discontinue these medications during each dosing occasion for up to 72 hours (from check-in into the research unit until released after the last study assessment for each dosing period).