All subjects will participate in a lead-in period, and qualifying subjects will continue into a short-term randomized treatment period. Subjects who complete the short-term period will be eligible to enter the long term extension period. Also, subjects in the short-term period who have an elevated blood sugar that requires additional medication for blood sugar control will be eligible to enter the long-term treatment extension period where they will receive metformin added onto their blinded study medication. Subjects with screening hemoglobin A1c (A1C) > 10.0% and ≤ 12.0%, who otherwise meet all inclusion/exclusion criteria, were eligible to enroll directly into Open-Label Treatment Cohort (Direct Enrollees) and receive open-label saxagliptin 10 mg. Those who completed the short-term period were eligible to enter into the long-term treatment extension period.Saxagliptin dose titration was not permitted.