Efficacy and safety of once-weekly versus once-daily basal insulin analogues in the treatment of type 2 diabetes mellitus: A systematic review and meta-analysis

Aim: To summarize the evidence of recently published randomized controlled trials (RCTs) studying efficacy, in terms of glycaemic control, and safety of the newly developed once-weekly basal insulin analogues.Methods: A systematic literature search was conducted through Medline (via PubMed), Cochrane Library and Google Scholar until June 30, 2023. Double independent study selection, data extraction and quality assessment were performed. Results were summarized with random-effects meta-analysis.Results: A total of 3962 patients with type 2 diabetes mellitus (T2DM) among nine RCTs were analysed. All RCTs had low risk of bias according to the Cochrane Collaboration risk-of-bias tool (RoB2). Once-weekly insulins demonstrated better efficacy in glycated haemoglobin (HbA1c) reduction (mean difference [MD]-0.13%, 95% confidence interval [CI]-0.23,-0.03; P = 0.08) and a significantly greater time in range compared with once-daily insulin analogues (MD 3.54%, 95% CI 1.56, 5.53; P = 0.005). Based on subgroup analyses, the reduction in HbA1c and the odds of achieving an end-of-treatment HbA1c <6.5% were significantly greater for icodec compared to the once-daily insulin (MD-0.18%, 95% CI-0.27,-0.09 [P < 0.001] and odds ratio [OR] 1.75, 95% CI 1.34, 2.29 [P < 0.001], respectively). Once-weekly insulins were associated with higher odds of level 1 hypoglycaemia during the 24-hour period (OR 1.3, 95% CI 1.04, 1.64; P = 0.02) but were safer in terms of level 2 or 3 nocturnal hypoglycaemic events (OR 0.74, 95% CI 0.56, 0.97; P = 0.03). No difference was observed regarding serious adverse events between the two groups.Conclusion: The once-weekly basal insulin analogues seem to be at least equally efficient in glycaemic management and safe compared to once-daily injections in people with T2DM. Phase 4 RCTs are expected to shed further light on the effectiveness and safety of once-weekly insulin therapy over the long term.