GLP-1 treatments have the potential to revolutionize the care of diabetes and improve health status more broadly. While these medications are effective, they’re also expensive. Unfortunately, affordability challenges cause many GLP-1 users to stop treatment before it can help.
For much of 2024, access challenges for GLP-1 medicines were widespread, primarily due to demand outpacing manufacturing. Now, supply is sufficient enough that flexibilities around use of compounded medications is winding down. However, the price of these medications and the ability for patients to tolerate ongoing therapy remain limiting factors.
To better understand what may undermine persistency of treatment, we analyzed Arcadia’s proprietary research data asset. What we found might not be what you’d think.
Let’s begin with a quick introduction to these medications. GLP-1 receptor agonists are a reformulation of a human hormone that impacts glucose levels and hunger. Supported by NIH research over 30 years ago, this compound was isolated and then produced as a pharmaceutical beginning in 2005. Since then, they’ve shown remarkable effectiveness in patients with diabetes, reducing mortality over 20% through a combination of weight loss and improved glucose control. Additional research indicates GLP-1s can have a wide-range of additional benefits across conditions—both within the metabolic syndrome and beyond.
There’s likely someone in your life that could benefit—or already is benefitting—from these medications. Between 2019 and 2023, use of GLP-1s in the U.S. rose from 21,000 to 174,000 individuals. That’s an increase greater than 700%.
But starting GLP-1 therapy is not the same as realizing a health benefit. Looking at the experience of patients in the Arcadia database, we see that while over 1,000,000 individuals filled a prescription for these agents between 2022 and 2024, only 34% remained on the therapy after 6 months. And while these “persistent” users experienced, on average, a weigh loss of more than 35 pounds, the reality is that most people who started treatment may not realize any benefit. That’s because half the money spent on GLP-1 therapy was on treatment that lasted less than six months.
We’ve seen this problem before with similarly high-impact therapies like statins and aspirin in high-risk cardiovascular disease. In those cases, there was an additional concerning trend: that rates of persistency differed by race and sex.
To dig a little deeper and examine what characteristics were associated with GLP-1 persistency, Arcadia examined the association between age, sex, race, and BMI on likelihood to discontinue GLP-1 treatment before six months.
Here are the key associations we observed:
| Age Group | Persistency Rate |
|---|---|
| 18–25 | 23.3% |
| 26–45 | 32.5% |
| 46–64 | 42.1% |
| 65+ | 48.7% |
Persistency rises sharply with age, nearly tripling between the youngest and oldest cohorts.
| BMI Category | Persistency Rate |
|---|---|
| 25–29.9 | 36.9% |
| 30–39.9 | 31.8% |
| 40–49.9 | 29.2% |
| 50–59.9 | 27.3% |
| 60–69.9 | 26.5% |
| 70+ | 26.2% |
Most surprisingly, we observed that individuals with the highest BMI’s were most likely to discontinue therapy in less than six months.
| Sex | Persistency Rate |
|---|---|
| Female | 43.1% |
| Male | 44.2% |
| Race | Persistency Rate |
|---|---|
| Asian | 41.5% |
| Black or African American | 42.7% |
| White | 44.6% |
Persistency rates were relatively similar across sex and racial groups, with slightly higher adherence among white patients.
While the analysis was observational and cannot establish causation, several plausible factors may help explain the differences in persistency:
1. Cost and Affordability: Out-of-pocket costs can be significant, especially for those without consistent commercial coverage. Younger and lower-income individuals may be more sensitive to cost barriers.
2. Side Effects and Tolerability: GLP-1s are known for gastrointestinal side effects. If certain groups are more prone—or less tolerant—to these effects, they may be more likely to discontinue early.
3. The Food Addiction Hypothesis: There’s emerging evidence that GLP-1s may modulate appetite centers differently across individuals. Psychological and behavioral factors might influence perceived benefit and adherence.
4. Coverage Variation: While GLP-1 coverage for diabetes is standard, broader coverage for obesity is variable and some patients may have had higher out-of-pocket costs or no coverage for these medications tied to their health plan.
5. 2024 Drug Shortages: Throughout 2024, intermittent supply constraints affected access to semaglutide and tirzepatide. These disruptions may have disproportionately affected specific populations or payer types.
Understanding which patients stay on GLP-1s helps organizations better estimate the drugs’ real-world effectiveness and cost impact. It also provides a starting point for improving support strategies—whether through targeted education, care management, or benefits design.
Just as health systems responded to disparities in statin adherence with outreach and protocol standardization, we now face a similar opportunity with GLP-1s.
Persistency on GLP-1 therapy is shaped by more than clinical need. It reflects broader realities of affordability, access, and lived experience. By identifying the characteristics of persistent users, we can begin designing better interventions to support all patients in achieving the full potential of these therapies.