Growth of GLP-1 therapies has reshaped the market | PBMI 2026

Nearly half of the growth in prescription drug sales now can be attributed to GLP-1 therapies. On the diabetes side, GLP-1s, including Mounjaro and Ozempic, make up a $98 billion market, with a 16.5% growth on a year-over-year basis. GLP-1 therapies for weight loss, including Zepbound and Wegovy, saw a 75% year-over-year growth and generated $55 billion in sales in the last 12 months, which is up from $2 million in 2022, said Scott Biggs, director of supplier services at IQVIA at the keynote at the Pharmacy Benefit Management Institute annual meeting in Orlando.

The economics of which segments are filling these prescriptions has changed, Biggs said. Retailers, including independent pharmacies, are making very conscious decisions about whether to fill these prescriptions. For example, a year ago, about 48.5% of independents were not filling prescriptions for GLP-1 for weight loss; now 35% of independent pharmacies won’t fill weight loss GLP-1 prescriptions and 8% won’t fill prescriptions for diabetes GLP-1. “Independents are starting to embrace the weight loss GLP-1s,” he said.

About 80% of the GLP-1 market is being sold through retail pharmacies, but Biggs said mail delivery is increasing as direct-to-consumer options, while small, become more popular. Mail delivery now accounts for 12.9% of GLP-1 prescriptions.

The growth of the GLP-1 category has also reshaped the diabetes market. Sales of insulin products have slowed. Insulin now makes up just 9.8% of the diabetes market, down from 38.4% of the diabetes market. In terms of the number of prescriptions, insulin products are 16% of the prescriptions filled, down from 21%.

Related: What health plans need to know about Medicare's GLP-1 Bridge program

Biggs said he is beginning to see sizeable demand for GLP-1 therapies for weight loss through Medicare Part D’s Bridge program, a CMS demonstration program that began July 1, 2026, that provides some beneficiaries with access to Wegovy, Zepbound, and Foundayo for $50.

“In the first three days, we showed 9,000 claims paid. By my estimates, that would be almost $2 million paid for by CMS,” he said.

Biggs expects both sales and the number of prescriptions of GLP-1 products to increase as new therapies become available and are approved for other indications. The pipeline for GLP-1 products has expanded beyond obesity and diabetes, with about 200 molecules in development, Biggs said.

"There are also some emerging frontiers going on in this area,” he said during his presentation. “One that we’ve been talking about is mental health. There are some trials that suggest there are some possibilities for GLP-1s to improve some depressive symptoms. I’ve heard a lot about substance use disorders. There are links found between the GLP-1s to reduce alcohol consumption, opioid overdose risk, and tobacco use.”

In the short term, the pipeline for GLP-1 is assessing therapies that could minimize side effects to improve tolerability and maintain muscle mass and achieve a higher weight loss, either alone or in combination.

Longer term, Biggs said researchers are also exploring GLP-1 therapies for decreasing the risk of prostate cancer progression, endometrial cancer, and some obesity-related cancers; addressing women's health for fertility and ovulation and PCOS [polycystic ovary syndrome]; and addressing systemic inflammation for respiratory disease and neurodegenerative diseases, such as dementia and Alzheimer’s disease.

“This will be an interesting category to watch to see how the market goes,” he said. “Obesity can be linked to many other things in a person's system. Researchers are talking about immune pathway overlap, plasticity and whether it alters the immune disease phenotype; some weight-dependent pharmacology; microbiome dysbiosis; and biomechanical stress.”

Other points from IQVIA’s 2026 Use of Medicines Trend report:

• Total prescription medicine use increased 1.5%, reaching 210 billion days of therapy in 2025.
• The U.S. market at net prices grew 10.6% in 2025 and an average of 9.3% annually over the last five years.
• Patient out-of-pocket costs reached a record $110 billion in 2025, increasing by $6 billion.
• Pricing pressures and patent expirations will slow growth through 2030, offset by continued uptake of innovative therapies.
• U.S. medicine spending at net prices is forecast to grow 4.5% to 7.5% and 6% to 9% at list prices.