A Study to Evaluate Combining Metformin With Muraglitazar or Pioglitazone in Type 2 Diabetics

Inclusion Criteria: * Type 2 diabetics * HbA1c ≥7.0% and ≤10.0%,currently receiving a stable dose of metformin 1500 to 2550 mg/day for at least 6 weeks prior to screening were enrolled in this study. * Fasting C-peptide ≥1.0 ng/mL * BMI≤41 kg/m2 mean fasting serum trig. ≤600 g/dL Exclusion Criteria: * symptomatic type 2 diabetics with \> 10% weight loss 3 months prior to study * history of diabetic ketoacidosis, hyperosmolar nonketotic coma, insulin therapy, inability to take muraglitazar, pioglitazone, or metformin according to investigator brochure or labeling * History of MI (myocardial infarction), coronary angioplasty or bypass graft(s), valvular disease or repair, unstable angina pectoris, transient ischemic attack (TIA), cerebrovascular attack, or cerebrovascular accident (CVA) within 6 months, congestive heart failure (NYHA Class III and IV, uncontrolled hypertension, history of, or renal disease, peripheral vascular disease (PVD), pulmonary disease, gastrointestinal disease, active liver disease or endocrine disease.