Comparative efficacy and safety of weekly tirzepatide versus weekly insulin in type 2 diabetes: A network meta-analysis of randomized clinical trials.

AIM: To compare the efficacy and safety profiles of recent innovations in type 2 diabetes mellitus (T2DM), which include once-weekly formulations such as tirzepatide, a dual glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide receptor agonist, and once-weekly insulin options such as icodec and basal insulin Fc. METHODS: A systematic search of the PubMed, Scopus, Cochrane, and Web of Science databases was conducted. The network meta-analysis protocol was registered at OSF registries (https://osf.io/gd67x). The primary outcome of interest was change in glycated haemoglobin (HbA1c), with change in fasting plasma glucose (FPG), body weight, incidence of hypoglycaemia, and treatment discontinuation as secondary outcomes. RESULTS: Tirzepatide exhibited superior efficacy in reducing HbA1c levels compared with insulin therapies, with the 15-mg dose showing the most significant reduction (mean difference [MD] -1.27, 95% confidence interval [CI] -1.49; -1.0). In terms of FPG reduction, tirzepatide 15 mg ranked highest (MD -0.70, 95% CI -1.05; -0.34), followed by tirzepatide 10 mg and 5 mg. Additionally, tirzepatide led to substantial weight loss, with the 15-mg dose exhibiting the most pronounced effect (MD -12.13, 95% CI -13.98; -10.27). However, a higher incidence of adverse events (AEs) and treatment discontinuation were associated with tirzepatide, particularly at higher doses. CONCLUSION: Tirzepatide, particularly at higher doses, demonstrates superior efficacy in lowering HbA1c and reducing hypoglycaemia risk compared with weekly insulin. However, its use is also associated with a higher incidence of AEs and treatment discontinuation.