Liraglutide vs insulin glargine and placebo in combination with metformin and sulfonylurea therapy in type 2 diabetes mellitus (LEAD-5 met+SU): a randomised controlled trial

AIMS/HYPOTHESIS: The aim of the study was to compare the efficacy and safety of liraglutide in type 2 diabetes mellitus vs placebo and insulin glargine (A21Gly,B31Arg,B32Arg human insulin), all in combination with metformin and glimepiride. METHODS: This randomised (using a telephone or web-based randomisation system), parallel-group, controlled 26 week trial of 581 patients with type 2 diabetes mellitus on prior monotherapy (HbA(1c) 7.5–10%) and combination therapy (7.0–10%) was conducted in 107 centres in 17 countries. The primary endpoint was HbA(1c). Patients were randomised (2:1:2) to liraglutide 1.8 mg once daily (n = 232), liraglutide placebo (n = 115) and open-label insulin glargine (n = 234), all in combination with metformin (1 g twice daily) and glimepiride (4 mg once daily). Investigators, participants and study monitors were blinded to the treatment status of the liraglutide and placebo groups at all times. RESULTS: The number of patients analysed as intention to treat were: liraglutide n = 230, placebo n = 114, insulin glargine n = 232. Liraglutide reduced HbA(1c) significantly vs glargine (1.33% vs 1.09%; −0.24% difference, 95% CI 0.08, 0.39; p = 0.0015) and placebo (−1.09% difference, 95% CI 0.90, 1.28; p < 0.0001). There was greater weight loss with liraglutide vs placebo (treatment difference –1.39 kg, 95% CI 2.10, 0.69; p = 0.0001), and vs glargine (treatment difference −3.43 kg, 95% CI 4.00, 2.86; p < 0.0001). Liraglutide reduced systolic BP (−4.0 mmHg) vs glargine (+0.5 mmHg; −4.5 mmHg difference, 95% CI 6.8, −2.2; p = 0.0001) but not vs placebo (p = 0.0791). Rates of hypoglycaemic episodes (major, minor and symptoms only, respectively) were 0.06, 1.2 and 1.0 events/patient/year, respectively, in the liraglutide group (vs 0, 1.3, 1.8 and 0, 1.0, 0.5 with glargine and placebo, respectively). A slightly higher number of adverse events (including nausea at 14%) were reported with liraglutide, but only 9.8% of participants in the group receiving liraglutide developed anti-liraglutide antibodies. CONCLUSIONS/INTERPRETATION: Liraglutide added to metformin and sulfonylurea produced significant improvement in glycaemic control and bodyweight compared with placebo and insulin glargine. The difference vs insulin glargine in HbA(1c) was within the predefined non-inferiority margin. TRIAL REGISTRATION: CLINICALTRIALS.GOV NCT00331851: FUNDING: THE STUDY WAS FUNDED BY NOVO NORDISK A/S. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00125-009-1472-y) contains a list of members of the LEAD-5 Study Group, which is available to authorised users.