Conditions: Diabetes Mellitus, Type 2
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 1462
Healthy volunteers: no

Brief summary:
The purpose of this clinical research study is to learn whether Saxagliptin added to Metformin therapy is more effective than Metformin alone as a treatment for type 2 diabetic subjects who are not sufficiently controlled with Metformin alone

Detailed description:
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 pioglitizone added onto their blinded study medication

Arms:
arm 1: Pioglitazone 15-45 mg (as needed for rescue) arm 2: Pioglitazone 15-45 mg (as needed for rescue) arm 3: Pioglitazone 15-45 mg (as needed for rescue) arm 4: Pioglitazone 15-45 mg (as needed for rescue)

Interventions: intervention 1: Saxagliptin + Metformin intervention 2: Saxagliptin + Metformin intervention 3: Saxagliptin + Metformin intervention 4: Placebo + Metformin intervention 5: Pioglitazone
Intervention descriptions: intervention 1: Tablets, Oral, 2.5 mg Saxagliptin (plus flexible metformin dose), Once daily (24 weeks ST, 42 months LT) intervention 2: Tablets, Oral, 5 mg Saxagliptin (plus flexible metformin dose), Once daily (24 weeks ST, 42 months LT) intervention 3: Tablets, Oral, 10 mg Saxagliptin (plus flexible metformin dose), Once daily (24 weeks ST, 42 months LT) intervention 4: Tablets, Oral, 0 mg, Once daily (24 weeks ST, 42 months LT) intervention 5: Tablets, Oral, 15 - 45 mg (as needed for rescue)

Protocol document: