Evaluation of Fixed Dose Combination of Glimepiride and Metformin in Chinese Type 2 Diabetes Patients Inadequately Controlled With Metformin

Primary Objective: * To evaluate the efficacy of fixed dose combination of glimepiride and metformin (AMARYL M 1/250mg) in comparison with glimepiride (AMARYL) alone in terms of glycemic control as reflected by HbA1c during a 20-week treatment period in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin. Secondary Objectives: * To evaluate the percentage of patients reaching HbA1c \< 7% or HbA1c ≤ 6.5% of fixed dose combination of 1 mg glimepiride and 250 mg metformin (AMARYL M 1/250mg) in comparison with glimepiride (AMARYL) alone at week 20. * To evaluate the effect on Fasting Plasma Glucose of fixed dose combination of glimepiride and metformin (AMARYL M 1/250mg) in comparison with glimepiride (AMARYL) alone at week 20. * To assess the safety and tolerability of fixed dose combination of glimepiride and metformin (AMARYL M 1/250mg).