Efficacy and Safety of Saxagliptin VS. Glimepiride in Chinese T2DM Patients Controlled Inadequately With Metformin

Inclusion Criteria: * For inclusion in the study subjects should fulfill the following criteria: * Provision of informed consent prior to any study specific procedures * Type2 diabetic patients had been on stable, maximum tolerated doses of metformin (≧1500mg/d, ≧8 weeks) * Male or female age ≧ 25 years and ≦75 years old * HbA1c ≧7.0 and ≦9.5% * BMI ≧ 20 and ≦ 30 kg/m2 Exclusion Criteria: * Subjects should not enter the study if any of the following exclusion criteria are fulfilled: * Known or suspected allergy to trial products or related products. * Impaired renal function defined as serum-creatinine ≥ 1.5 mg/dL (≥ 132.6 μmol/l). * Acute or chronic disease which may cause tissue hypoxia such as cardiac or respiratory failure, shock. * Hepatic insufficiency, acute alcohol intoxication, alcoholism. * Subjects has a clinically significant, active (or over the past 12 months) cardiovascular history (including a history of myocardial infarction (MI), arrhythmias or conduction delays on ECG, unstable angina, or decompensated heart failure (New York Heart Association-class Ⅲ and Ⅳ). * Proliferative retinopathy or muscular oedema requiring acute treatment. * Lactation. * Pregnant or positive pregnancy test at screening, nursing mother, or unwillingness to use adequate contraception (adequate contraceptive measures are sterilization, intrauterine device, oral contraceptives or barrier methods). * Treatment with systemic corticosteroids within the past two months prior to screening. * Tested positive for glutamic acid decarboxylase antibody. * Receipt of any investigational drug within 1 month prior to this trial.