Efficacy and safety of exenatide once weekly versus metformin, pioglitazone, and sitagliptin used as monotherapy in drug-naive patients with type 2 diabetes (DURATION-4): a 26-week double-blind study

OBJECTIVE: To test the safety and efficacy of exenatide once weekly (EQW) compared with metformin (MET), pioglitazone (PIO), and sitagliptin (SITA) over 26 weeks, in suboptimally treated (diet and exercise) drug-naive patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Patients were randomized to subcutaneous (SC) EQW 2.0 mg + oral placebo (n = 248), MET 2,000 mg/day + SC placebo (n = 246), PIO 45 mg/day + SC placebo (n = 163), or SITA 100 mg/day + SC placebo (n = 163) for 26 weeks. MET and PIO therapies were increased to maximum-tolerated dosages. Injections with EQW or placebo were administered weekly, while oral medication or placebo was administered daily. RESULTS: Baseline characteristics were as follows: 59% men, 67% Caucasian, mean age 54 years, HbA(1c) 8.5%, fasting serum glucose 9.9 mmol/L, body weight 87.0 kg, and diabetes duration 2.7 years. HbA(1c) reductions (%) at 26 weeks (least-squares means) with EQW versus MET, PIO, and SITA were -1.53 vs. -1.48 (P = 0.620), -1.63 (P = 0.328), and -1.15 (P < 0.001), respectively. Weight changes (kg) were -2.0 vs. -2.0 (P = 0.892), +1.5 (P < 0.001), and -0.8 (P < 0.001), respectively. Common adverse events were as follows: EQW, nausea (11.3%) and diarrhea (10.9%); MET, diarrhea (12.6%) and headache (12.2%); PIO, nasopharyngitis (8.6%) and headache (8.0%); and SIT, nasopharyngitis (9.8%) and headache (9.2%). Minor (confirmed) hypoglycemia was rarely reported. No major hypoglycemia occurred. CONCLUSIONS: EQW was noninferior to MET but not PIO and superior to SITA with regard to HbA(1c) reduction at 26 weeks. Of the agents studied, EQW and MET provided similar improvements in glycemic control along with the benefit of weight reduction and no increased risk of hypoglycemia.