A Systematic Review and Meta-Analysis of Efficacy and Safety of Liraglutide in Patients with Type 2 Diabetes Mellitus.

BACKGROUND

Obesity plays a pivotal and modifiable role in the development and progression of type 2 diabetes mellitus (T2DM). Clinicians increasingly use lower doses of liraglutide (1.2 mg and 1.8 mg) to achieve clinically meaningful weight loss while maintaining effective glycemic control in people with T2DM and obesity. In this meta-analysis, we compared the efficacy and safety of liraglutide 1.2 mg and 1.8 mg in this population.

METHODS

We systematically searched PubMed, the Cochrane Central Register of Controlled Trials, LENS, ClinicalTrials.gov, and the Virtual Health Library (VHL) for randomized controlled trials published in English up to 30 September 2024. We included trials with 24-52 weeks of treatment that evaluated liraglutide at doses of 1.2 mg or 1.8 mg against placebo or glucose-lowering therapies (GLTs). Comparators included insulin, sulfonylureas, dipeptidyl peptidase-4 inhibitors (DPP-4i), sodium-glucose cotransporter-2 inhibitors (SGLT2i), other glucagon-like peptide-1 receptor agonists (GLP-1RAs), and oral antidiabetic drugs (OADs). We assessed changes in body weight and HbA1c as efficacy outcomes and evaluated the occurrence of nausea and vomiting as safety outcomes. Two reviewers independently extracted data and assessed study quality using PRISMA guidelines and the Cochrane Risk of Bias 2 tool.

RESULTS

We included 25 RCTs comprising 10,593 participants. Liraglutide 1.2 mg (8 studies, 3,455 participants) produced a mean weight reduction of -1.24 kg versus GLTs, -0.75 kg versus placebo, and -2.46 kg versus OADs. Liraglutide 1.8 mg (22 studies, 8,259 participants) achieved significantly greater weight loss of -2.30 kg versus GLTs, -1.93 kg versus placebo, and -2.81 kg versus OADs. When compared with oral semaglutide, exenatide, dulaglutide, lixisenatide, and albiglutide, liraglutide showed comparable efficacy. For glycemic control, liraglutide 1.2 mg reduced HbA1c by -0.24% versus OADs, while liraglutide 1.8 mg reduced HbA1c by -0.26% versus GLTs. Liraglutide 1.2 mg showed a numerically lower incidence of nausea and similar rates of vomiting compared with other GLP-1RAs.

CONCLUSION

Liraglutide 1.2 mg and 1.8 mg doses improve weight and glycemic outcomes with a favourable safety profile, supporting its role as an effective therapeutic option for comprehensive management of T2DM with comorbid obesity.