Exenatide twice daily versus glimepiride for prevention of glycaemic deterioration in patients with type 2 diabetes with metformin failure (EUREXA): an open-label, randomised controlled trial.

BACKGROUND: Glycaemic control deteriorates progressively over time in patients with type 2 diabetes. Options for treatment escalation remain controversial after failure of first-line treatment with metformin. We compared add-on exenatide with glimepiride for durability of glycaemic control in patients with type 2 diabetes inadequately controlled by metformin alone. METHODS: We did an open-label, randomised controlled trial at 128 centres in 14 countries between Sept 5, 2006, and March 29, 2011. Patients aged 18-85 years with type 2 diabetes inadequately treated by metformin were randomly assigned via a computer-generated randomisation sequence to receive exenatide twice daily or glimepiride once daily as add-on to metformin. Randomisation was stratified by predetermined categories of glycated haemoglobin (HbA(1C)) concentration. The primary outcome was time to inadequate glycaemic control and need for alternative treatment, defined as an HbA(1c) concentration of more than 9% after the first 3 months of treatment, or more than 7% at two consecutive visits after the first 6 months. Analysis was by intention to treat. This trial is registered with EudraCT, number 2005-005448-21, and ClinicalTrials.gov, number NCT00359762. FINDINGS: We randomly assigned 515 patients to the exenatide group and 514 to the glimepiride group, of whom 490 versus 487 were the intention-to-treat population. 203 (41%) patients had treatment failure in the exenatide group compared with 262 (54%) in the glimepiride group (risk difference 12·4 [95% CI 6·2-18·6], hazard ratio 0·748 [0·623-0·899]; p=0·002). 218 (44%) of 490 patients in the exenatide group, and 150 (31%) of 487 in the glimepiride group achieved an HbA(1c) concentration of less than 7% (p<0·0001), and 140 (29%) versus 87 (18%) achieved concentrations of 6·5% and less (p=0·0001). We noted a significantly greater decrease in bodyweight in patients given exenatide than in those given glimepiride (p<0·0001). Five patients in each treatment group died from causes unrelated to treatment. Significantly fewer patients in the exenatide group than in the glimepiride group reported documented symptomatic (p<0·0001), nocturnal (p=0·007), and non-nocturnal (p<0·0001) hypoglycaemia. Discontinuation because of adverse events (mainly gastrointestinal) was significantly higher (p=0·0005) in the exenatide group than in the glimepiride group in the first 6 months of treatment, but not thereafter. INTERPRETATION: These findings provide evidence for the benefits of exenatide versus glimepiride for control of glycaemic deterioration in patients with type-2 diabetes inadequately controlled by metformin alone. FUNDING: Eli Lilly and Company; Amylin Pharmaceuticals.