All eligible subjects will receive a single-blind placebo medication during a 1-week lead-in period prior to randomization. All arms may include the addition of open label medication described (as needed for rescue based on protocol specific criteria). Rescue medication is defined as the addition of an approved, appropriate antihyperglycemic agent, except metformin, used according to conventional standards of care, to treat hyperglycemia, which may therefore allow the subject to remain in the trial
