Once-Daily Oral Semaglutide Versus Injectable GLP-1 RAs in People with Type 2 Diabetes Inadequately Controlled on Basal Insulin: Systematic Review and Network Meta-analysis

Diabetes Ther. 2021 May;12(5):1325-1339. doi: 10.1007/s13300-021-01034-w. Epub 2021 Mar 16.


Introduction: The relative efficacy and safety of once-daily oral semaglutide vs. injectable glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in subjects with type 2 diabetes (T2D) inadequately controlled on basal insulin were assessed using network meta-analysis (NMA).

Methods: A systematic literature review (SLR) was performed to identify randomised controlled trials of GLP-1 RAs in this population. Data at 26 ± 4 weeks were extracted for efficacy and safety outcomes feasible for the NMA: change from baseline in glycated haemoglobin (HbA1c), weight and blood pressure; HbA1c target levels (< 7.0% and ≤ 6.5%); composite endpoint; incidence of nausea, vomiting or diarrhoea. Comparators of interest were all licensed doses of dulaglutide, exenatide, liraglutide, lixisenatide and once-weekly injectable semaglutide.

Results: The NMA included seven trials. Once-daily oral semaglutide 14 mg was associated with significantly greater HbA1c reductions vs. most comparators (treatment differences: - 0.42 to - 1.32%); differences vs. once-weekly injectable semaglutide (0.5 mg and 1 mg doses) were not statistically significant. Once-daily oral semaglutide 14 mg was associated with significantly greater weight reductions vs. exenatide 2 mg and lixisenatide 20 μg (- 2.21 and - 2.39 kg respectively); non-statistically significant weight reductions in favour of once-daily oral semaglutide 14 mg were observed vs. all other comparators except once-weekly injectable semaglutide 1 mg. Similar trends were observed for the proportion of subjects achieving HbA1c < 7.0% and ≤ 6.5% and the composite endpoint. Once-daily oral semaglutide 14 mg was associated with similar odds of experiencing nausea, vomiting or diarrhoea vs. all comparators.

Conclusion: Once-daily oral semaglutide 14 mg, as an add-on to basal insulin, is an efficacious treatment for reducing HbA1c and weight and meeting glycaemic targets at 26 ± 4 weeks. Once-daily oral semaglutide 14 mg also offers the option of an oral treatment with similar or better efficacy and similar tolerability vs. most injectable GLP-1 RAs.

Keywords: Basal insulin; GLP-1; Glycaemic control; Network meta-analysis; Semaglutide; Systematic review; Type 2 diabetes.