Comparative Effectiveness and Safety of Once-Weekly Injectable Semaglutide Versus Dulaglutide in Individuals with Type 2 Diabetes Managed in UK Primary Care: A Population-Based Cohort Study
Abstract
Background: The SUSTAIN-7 trial demonstrated greater HbA1c and bodyweight reductions with once-weekly semaglutide versus dulaglutide in type 2 diabetes, but strict eligibility criteria limit external validity. We evaluated the comparative real-world effectiveness and safety of these agents in UK primary care.
Methods: Using the IQVIA Medical Research Data (IMRD) incorporating data from THIN, a Cegedim Database, we included adults with type 2 diabetes initiating semaglutide or dulaglutide between 01-Jan-2019 and 01-Dec-2022, followed through 30-Jun-2023. Co-primary outcomes were 1-year changes in HbA1c and bodyweight, estimated using a new-user, active-comparator cohort design with marginal structural models and inverse probability of treatment weighting. Treatment heterogeneity was assessed in the primary per-protocol analysis by SUSTAIN-7 trial-eligibility. Safety events were assessed while-on-treatment.
Findings: Among 6616 new users, 4636 (70.1%) remained on-treatment and 1980 (29.9%) discontinued early. Semaglutide new users (n = 1901) achieved greater 1-year reductions than dulaglutide new users (n = 2735) in HbA1c (estimated treatment difference [ETD] -0.22 percentage points [95% CI -0.30, -0.15]) and bodyweight (ETD -1.92 kg [95% CI -2.91, -0.93]). While semaglutide's benefits were preserved across the 87.7% (n = 4064) not meeting SUSTAIN-7 trial-eligibility (HbA1c: ETD -0.23 percentage points [95% CI -0.31, -0.15]; bodyweight: ETD -2.01 kg [95% CI -3.07, -0.95]), reductions in HbA1c and bodyweight were greater among trial-eligible individuals (12.3%; n = 572) for both agents (trial-eligible [semaglutide/dulaglutide] versus non-eligible [semaglutide/dulaglutide] individuals, HbA1c: -1.10/-1.02 versus -0.83/-0.60 percentage points; bodyweight: -5.72/-4.18 versus -5.50/-3.49 kg). Early discontinuers showed attenuated treatment effects and higher gastrointestinal event rates than those remaining on-treatment (23.5-26.1 versus 10.6-13.8 per 100 person-years).
Interpretation: New users of semaglutide achieved greater reductions in HbA1c and bodyweight than new users of dulaglutide with comparable safety, with benefits preserved across SUSTAIN-7 trial-eligible and non-eligible individuals, supporting preferential use of semaglutide in UK clinical practice.
Funding: Swiss National Science Foundation.
Authors: Franziska S Ulrich, Morten Frost Nielsen, Nicola Napoli, Andrea M Burden
Journal: The Lancet regional health. Europe