Aim: To assess and compare the efficacy and safety of liraglutide with those of glimepiride, both in combination with metformin for the treatment of type 2 diabetes in Asian population from China, South Korea and India. Methods: A 16-week, randomized, double-blind, double-dummy, four-arm, active control trial was carried out. In total, 929 subjects with type 2 diabetes with a mean (+/- s.d.) age of 53.3 +/- 9.5 years, HbA(1c) of 8.6 +/- 1.0% and body weight of 68.1 +/- 11.7 kg were randomized (liraglutide 0.6, 1.2 or 1.8 mg once daily or glimepiride 4 mg once daily all in combination with metformin: 1 : 1 : 1 : 1). One subject withdrew immediately after randomization and before exposure. Results: HbA(1c) was significantly reduced in all groups compared with baseline. Treatment with liraglutide 1.2 and 1.8 mg was non-inferior to glimepiride (mean HbA(1c) reduction: 1.36% points, 1.45% points and 1.39% points, respectively). No significant difference was shown in the percentage of subjects reaching American Diabetes Association HbA(1c) target <7% or American Association of Clinical Endocrinologists target <= 6.5% between liraglutide 1.2 and 1.8 mg and glimepiride. Liraglutide was associated with a 1.8-2.4 kg mean weight reduction, compared with a 0.1 kg mean weight gain with glimepiride. Liraglutide led to a significantly greater reduction in systolic blood pressure (SBP) compared with glimepiride. Two subjects in the glimepiride group reported major hypoglycaemia while none in the liraglutide groups. Liraglutide was associated with about 10-fold lower incidence of minor hypoglycaemia than glimepiride. Gastrointestinal disorders were the most common adverse events (AEs) for liraglutide, but were transient and resulted in few withdrawals. Conclusions: In Asian subjects with type 2 diabetes, once-daily liraglutide led to improvement in glycaemic control similar to that with glimepiride but with less frequent major and minor hypoglycaemia. Liraglutide also induced a significant weight loss and reduced SBP and was generally well tolerated. The most frequently reported AE was transient nausea. The effect of liraglutide in this Asian population is comparable to the effects seen in Caucasian, African American and Hispanic populations in global liraglutide phase 3 trials.