FDA Takes Aim at GLP-1 Compounders in Pharmacies

Regulatory Shift Targets Compounded GLP-1 Drugs: What the FDA’s Latest Proposal Means

On May 1, 2026, the U.S. Food and Drug Administration (FDA) announced a proposal that could reshape the market for compounded semaglutide, tirzepatide, and liraglutide. If finalized, the rule would exclude these three glucagon-like peptide-1 (GLP-1) receptor agonists from the 503B Bulks List, the regulatory pathway that has allowed large-scale compounding of these drugs by outsourcing facilities. Industry observers, including attorneys Abha Kundi, Emily M. Cowley, Gayland O. Hethcoat II, Shoshana Golden, and Nardeen Billan of King & Spalding LLP, have described the move as a “shot heard ’round the pharmacy.”

The proposal is the latest chapter in a multiyear struggle between federal regulators, compounders, and branded manufacturers over access to these increasingly popular metabolic therapies.

How Compounding Regulations Work

To understand the FDA’s move, it helps to revisit the legal framework governing drug compounding. Under the Federal Food, Drug, and Cosmetic Act (FDCA), Sections 503A and 503B create two separate pathways for compounding.

Section 503A allows licensed pharmacists or physicians to prepare patient-specific custom medications. For example, a pharmacist might create a liquid version of a drug for someone who cannot swallow pills, or remove an inactive ingredient to which a patient is allergic. These compounds must be made pursuant to a valid prescription and are not subject to FDA premarket approval, but they are limited in volume and distribution.

Section 503B permits outsourcing facilities to compound larger quantities of drugs without individual patient prescriptions, provided two conditions are met. First, the bulk drug substance used must appear on the 503B Bulks List, a catalog of substances for which the FDA has determined there is a “clinical need.” Second, the drug can be compounded from a substance that is currently on the FDA’s drug shortage list at the time of compounding, distribution, and dispensing.

Importantly, when evaluating whether a substance meets the clinical need standard for the Bulks List, the FDA explicitly does not consider supply chain factors such as backorders, the cost advantage of compounded products over approved versions, or convenience of administration. This distinction has become central to the current debate.

The Rise of Compounded GLP-1s

The market for compounded GLP-1 drugs exploded in 2022. That year, demand for semaglutide (marketed by Novo Nordisk as Ozempic and Wegovy) and tirzepatide (marketed by Eli Lilly as Mounjaro and Zepbound) far exceeded available supply. Both drugs were placed on the FDA’s drug shortage list, opening a legal pathway for compounding.

Telehealth startups and cash-pay obesity clinics quickly seized the opportunity, offering lower-cost compounded versions to patients. According to the Kaiser Family Foundation, at their peak in 2024, compounded GLP-1 products accounted for up to 30% of the total U.S. supply of these drugs. A multibillion-dollar sub-industry had emerged, built largely on the regulatory allowances created by the shortages.

That foundation began to crack when the FDA declared the tirzepatide shortage over in December 2024 and the semaglutide shortage over in February 2025. The agency set phased enforcement deadlines requiring compounders to wind down operations. The Outsourcing Facilities Association (OFA) challenged both shortage determinations in federal court, and those cases are now pending appeal before the Fifth Circuit Court of Appeals.

Meanwhile, the FDA shifted to active enforcement. In March 2025, the agency issued 30 warning letters to telehealth companies accused of making misleading claims about their GLP-1 products. A second round of letters followed in April, targeting companies that marketed unapproved GLP-1, dual GLP-1/GIP, and triple agonist products. Some of these products were labeled “research use only,” but the FDA stated that this designation does not shield products being promoted for human consumption.

The May 1 Proposal

The OFA had nominated semaglutide, tirzepatide, and liraglutide for inclusion on the 503B Bulks List in 2024. In its May 1 notice, the FDA explained that after reviewing the nominations, it found “insufficient evidence of clinical need” to place any of the three on the list. Therefore, the agency proposed to exclude them entirely.

If finalized, the consequences would ripple across the supply chain.

For 503B outsourcing facilities, the exclusion would prohibit large-scale compounding of these three substances under the bulks list pathway. The only remaining avenue would be to rely on a future drug shortage listing. With both semaglutide and tirzepatide shortages officially resolved, that option is currently unavailable.

503A compounding pharmacies would retain narrow exceptions for patient-specific compounding, but those operations are limited in scope. For telehealth platforms and cash-pay clinics whose business models center on distributing compounded GLP-1s, the commercial viability of their model would be seriously questioned. For branded manufacturers Novo Nordisk and Eli Lilly, the proposal reinforces the market exclusivity of their FDA-approved products.

The public comment period for the proposed exclusion closes on June 29. Interested parties are encouraged to submit their views.

Looking Ahead: The July Advisory Committee

Beyond the GLP-1 proposal, the FDA has scheduled an advisory committee meeting for July 2026 to revisit the classification of 12 peptides. None of these are GLP-1 drugs, but the meeting has relevance for companies operating in the broader peptide compounding space.

In 2023, these 12 peptides were placed into Category 2, an FDA designation indicating that the bulk drug substances present significant safety concerns and may no longer be used in compounding. At the July meeting, the FDA will consider whether to include these peptides on the 503A Bulks List, which would effectively ban their use in patient-specific compounding as well.

The public comment period for this meeting closes on July 22. However, the FDA has specified that only comments received on or before July 9 will be provided directly to the advisory committee. Comments submitted between July 10 and July 22 will still be considered by the agency.

Frequently Asked Questions

Q: Does the FDA’s proposal affect all compounding of GLP-1 drugs immediately?

A: No. The proposal is open for public comment until June 29, 2026, and must be finalized before it takes effect. Even after finalization, limited patient-specific compounding under Section 503A would remain legal. The primary impact would be on large-scale 503B outsourcing facilities that compound these drugs from bulk substances.

Q: What is the difference between the 503A and 503B compounding pathways?

A: Section 503A covers traditional compounding for individual patients based on a valid prescription. These compounds are typically made in small batches by a local pharmacist or physician. Section 503B allows outsourcing facilities to compound larger volumes without patient-specific prescriptions, provided the bulk substance is on the 503B Bulks List or the drug is in shortage.

Q: Why did the FDA say there is no “clinical need” for compounded versions of these drugs?

A: The FDA evaluates clinical need based on factors such as whether an FDA-approved product addresses a medical condition or if a compounded version is necessary for specific patient needs like allergies to inactive ingredients. The agency does not consider supply backorders, cost savings, or convenience when making this determination. In its review, the FDA found no evidence that semaglutide, tirzepatide, or liraglutide meet the clinical need standard for the Bulks List.

Q: What are the 12 peptides being reviewed at the July advisory committee meeting?

A: The FDA has not publicly listed the 12 peptides in this announcement, but they are categorized as bulk drug substances that the agency believes present significant safety concerns. None of them are GLP-1 receptor agonists. The meeting will focus on whether to add these peptides to the 503A Bulks List, which would prohibit their use in patient-specific compounding.