Efficacy and tolerability of exenatide monotherapy in obese patients with newly diagnosed type 2 diabetes: a randomized, 26 weeks metformin-controlled, parallel-group study.

BACKGROUND: Incretin-based therapies provide additional options for treating type 2 diabetes. We aimed to evaluate the efficacy and tolerability of exenatide monotherapy in obese patients with type 2 diabetes. METHODS: A 26-week, metformin controlled, parallel-group study was conducted among antidiabetic drug-naive obese patients aged > 18 years, and with type 2 diabetes. Participating patients were randomly assigned to receive exenatide or metformin treatments. RESULTS: Fifty-nine patients (age (50.5 ± 8.6) years, body mass index (BMI) (30.2 ± 1.6) kg/m(2), and hemoglobin A1C (HbA(1C) (8.2 ± 1.2)%) were enrolled in the study. Glucose control and weight reduction improved in both groups receiving treatment. HbA(1C) and oral glucose tolerance test (OGTT) 2 hour glycemia reduction with exenatide was superior to that obtained with metformin ((-2.10 ± 1.79)% vs. (-1.66 ± 1.38)%, (-5.11 ± 2.68) mmol/L vs. (-2.80 ± 2.70) mmol/L, P < 0.05). Fast plasma glucose (FPG) reduction was not significantly different between the two groups ((-1.8 ± 2.0) mmol/L vs. (-1.6 ± 1.7) mmol/L, P > 0.05). Patients treated with exenatide achieved HbA(1C) of < 7% (97% of patients) and < 6.5% (79%) at end-point, vs. 93% and 73% with metformin (P > 0.05). Greater weight reduction was also achieved with exenatide ((-5.80 ± 3.66) kg) than with metformin ((-3.81 ± 1.38) kg, P < 0.01). Homeostasis model assessment of beta-cell function (HOMA-B) was not significantly increased, but the insulinogenic index and HOMA for insulin sensitivity (HOMA-S) were greatly improved in the exenatide group (P < 0.05). Nausea was the most common adverse effect in exenatide treatment (30% vs. 8%; P < 0.05), but most cases were of mild to moderate intensity. One case in the exenatide group was withdrawn early because of severe nausea. Hypoglycemia events were often observed during the first 4 weeks, with 12% of patients in the exenatide and 3.2% in metformin groups, respectively (P < 0.05). No incidents of severe hypoglycemia were reported. CONCLUSIONS: Exenatide demonstrated more beneficial effects on HbA(1C), weight reduction and insulin resistance during 26 weeks of treatment, but there were more hypoglycemic events and mild-to-moderate nausea compared with metformin. These results suggested that exenatide monotherapy may provide a viable treatment option in newly developed type 2 diabetes.