Safety and tolerability of acarbose in the treatment of type 1 and type 2 diabetes mellitus

Objective: To assess the safety profile of acarbose treatment over a 1-year period at a dose range of 50-300mg three times daily in patients with type 1 or type 2 diabetes mellitus. Study design and patients: In this 56-week, double-blind, parallel-group, multicentre comparison, patients were randomised to acarbose or placebo in a 2:1 ratio. An 8-week forced titration phase (from 50-300mg three times daily) was followed by a 48-week maintenance phase during which patients received the highest dose tolerated during titration. Patients were assessed at 13 visits with respect to adverse events/intercurrent illnesses, abnormal laboratory values (serum chemistry, urinalysis, complete blood and reticulocyte count, serum iron and total iron binding capacity, and serum vitamin B₆, B₁₂, D and folate levels), discontinuation rates, ECG findings, vital signs and evaluation of the patients' diaries with regard to gastrointestinal events. A total of 359 patients (acarbose 240, placebo 119) were valid for analysis; 21% had type 1 diabetes. Most patients received concomitant insulin or sulfonylurea treatment. Results: Study withdrawal was reported for 35% of acarbose and 24% of placebo recipients (p = 0.053); adverse events were the main reason for withdrawal in acarbose recipients (20%; placebo group 5%; p < 0.01). The most common adverse events for acarbose recipients were gastrointestinal (abdominal pain, flatulence and diarrhoea), which were more frequent than in placebo patients (p < 0.01). These events occurred more often early in the study and attenuated over time. Conclusion: Acarbose was safe and well tolerated by the majority of diabetic patients over a 1-year treatment period.