Efficacy and safety of acarbose in metformin-treated patients with type 2 diabetes

OBJECTIVE - To demonstrate the efficacy, tolerability, and safety of acarbose compared with placebo in patients with type 2 diabetes inadequately controlled with diet and metformin (2,000 or 2,500 mg/day in divided doses). RESEARCH DESIGN AND METHODS - This study had a multicenter randomized double-blind placebo-controlled parallel-group comparison design. The trial lasted 31 weeks and consisted of a 1-week screening period, a 6-week placebo pretreatment period, and a 24-week period of acarbose or placebo, with a forced titration from 25-50 mg t,i.d. and a titration of 50-100 mg tid that was based on glucose control. The primary efficacy variable was the mean change from baseline in HbA(1c). Secondary efficacy variables included mean changes from baseline in fasting and postprandial plasma glucose, serum insulin, and triglyceride levels. RESULTS - The addition of acarbose to patients on background metformin and diet therapy showed a statistically significant reduction in mean HbA(1c) of 0.65%. There were statistically significant reductions in fasting and postprandial plasma glucose and serum insulin levels compared with placebo. Gastrointestinal side effects were more frequently reported in the acarbose-treated patients. No significant differences in liver transaminase elevations were observed between patients treated with acarbose and those treated with placebo. CONCLUSIONS - The results of this study demonstrate that the addition of acarbose to patients with type 2 diabetes who are inadequately controlled with metformin and diet is safe and generally well tolerated and that it significantly lowers HbA(1c) and fasting and postprandial glucose and insulin levels.