Trends in 1-year persistence and adherence among initiators of high-potency, weight loss-indicated glucagon-like peptide 1 receptor agonists.
Level 3 - non-randomized controlled study
Retrospective cohort study using administrative claims data
PubMed 41760566 · doi:10.18553/jmcp.2026.32.3.281
What was done
Researchers analyzed integrated medical and pharmacy claims data from Prime Therapeutics (covering an average monthly membership of 17.9 million commercially insured individuals) from January 1, 2021, to June 30, 2024. They identified adults aged 19 years and older without diabetes who newly initiated high-potency, weight loss-indicated GLP-1 receptor agonists (semaglutide [Wegovy] or tirzepatide [Zepbound]). Eligible participants required continuous enrollment for 365 days pre- and post-index (maximum 15-day gap) and no GLP-1RA use in the baseline year. The primary outcome was 1-year treatment persistence, defined as having no gap greater than 60 days between consecutive prescription fills; product switching was permitted.
What was found
Of 62,650 new initiators, 33,607 met all inclusion criteria (mean age 45.7 years; 75.5% female). Overall 1-year persistence increased from 33.2% in 2021 to 60.9% in the first half of 2024 (1H 2024). For semaglutide, 1-year persistence rates from 2021 to 1H 2024 were 33.2%, 34.1%, 39.8%, and 58.6%, respectively. For tirzepatide, 1-year persistence rates in 2023 and 1H 2024 were 64.0% and 64.8%, respectively. Specific numerical adherence rates (proportion of days covered at least 80%) were not reported in the abstract.
Why it matters
Real-world persistence with anti-obesity GLP-1 receptor agonists has historically been low, but these findings show nearly a doubling in 1-year persistence between 2021 and 2024 as drug supply stabilized and newer options became available.
Limits
The sample is restricted to commercially insured adults without diabetes, limiting generalizability to Medicare, Medicaid, or uninsured populations. Nearly half of initiators (46.4%) were excluded due to enrollment criteria, introducing potential selection bias. Claims data lack clinical details regarding specific reasons for discontinuation, such as adverse effects, out-of-pocket costs, or reaching target weight.
Cited by
- supports Approximately 60% of people who initiate GLP-1 agonist therapy discontinue the medication within one to two years.