6 minute read | May.01.2026
On April 30, 2026, the U.S. Food and Drug Administration announced that it is proposing to exclude semaglutide, tirzepatide, and liraglutide from the 503B bulks list, finding no clinical need for outsourcing facilities to compound these drugs from bulk drug substances. The 503B bulks list identifies bulk drug substances that outsourcing facilities may use in compounding under section 503B of the Federal Food, Drug, and Cosmetic Act ("FD&C Act"). In most cases, outsourcing facilities cannot compound drugs using bulk drug substances unless the substance appears on the 503B bulks list or the compounded drug is on the FDA's drug shortage list at the time of compounding, distribution, and dispensing. The FDA is now inviting public comments through the docket by June 29, 2026, and will consider submitted comments before making a final determination.
Semaglutide (the active ingredient in Novo Nordisk's Ozempic and Wegovy) was placed on the FDA's drug shortage list in 2022, followed by tirzepatide (the active ingredient in Eli Lilly's Mounjaro and Zepbound) in December 2022. Under the FD&C Act, a shortage listing permits 503A compounders (state-licensed pharmacies and physicians) to compound copies of the drug and 503B outsourcing facilities (FDA-registered entities that manufacture large batches for healthcare entities) to compound from that drug's active ingredient — including drugs that are "essentially a copy" of an approved product. Compounding of GLP-1 medications quickly became a massive industry, as pharmacies and telehealth firms offered these medications at substantially lower prices than the branded products. That changed in late 2024 and early 2025 when the FDA declared the tirzepatide shortage resolved in October 2024 and the semaglutide shortage resolved in February 2025.
The Outsourcing Facilities Association ("OFA"), a trade group representing compounding pharmacies, challenged both shortage removals in the U.S. District Court for the Northern District of Texas, arguing the FDA's decisions were arbitrary and capricious. The OFA lost both bids at the district court, both drugs were removed from the shortage list, and FDA enforcement discretion periods for compounders expired, eliminating the primary legal basis for compounding "essentially a copy" of the branded products.
Today's announcement represents a potentially decisive regulatory blow to outsourcing facilities that have compounded GLP-1 medications. The proposal operates through a different legal pathway than the shortage list removals. Under section 503B of the FD&C Act, outsourcing facilities may only compound drugs using bulk drug substances if the substance appears on the 503B bulks list or the compounded drug is on the FDA's drug shortage list at the time of compounding, distribution, and dispensing. Currently, tirzepatide and semaglutide do not appear on either the 503B bulks list or the drug shortage list.
The significance of this proposal is that it would close one of the few remaining legal avenues for 503B outsourcing facilities to be able to resume large-scale compounding of these drugs. If finalized, semaglutide, tirzepatide, and liraglutide would be formally excluded from the 503B bulks list on a finding of no clinical need, meaning outsourcing facilities could not compound these drugs from bulk substances even if nominated to the list. This would effectively block large-scale, bulk compounding by outsourcing facilities unless the drugs return to FDA's shortage list.
Importantly, this proposal does not directly alter the legal framework for 503A compounding pharmacies. Section 503A pharmacies operate under a separate statutory provision and compound drugs pursuant to individual patient-specific prescriptions under state board of pharmacy oversight. They do not rely on the 503B bulks list to authorize their compounding activities, and the proposed exclusion of semaglutide, tirzepatide, and liraglutide from that list has no independent legal effect on their operations. However, this does not mean that 503A pharmacies may freely compound these GLP-1 medications.
The removal of semaglutide and tirzepatide from the FDA's drug shortage list in 2025 already eliminated the primary legal basis that had permitted 503A pharmacies to compound drugs that are "essentially a copy" of the commercially available branded products. Absent a shortage listing, 503A pharmacies are prohibited under section 503A of the FD&C Act from regularly or in inordinate amounts compounding drugs that are essentially copies of commercially available products.
Compounding of semaglutide or tirzepatide by 503A pharmacies may therefore be permissible only where there is a documented, individualized medical necessity for a formulation that is not merely a copy of the FDA-approved product — such as an allergy to a specific inactive ingredient in the branded version, a clinically justified need for a different concentration not commercially available, or a dosage form modification required for a specific patient population. Patient preference and cost savings alone are insufficient justifications. In short, while today's 503B bulks list proposal does not impose any new restrictions on 503A pharmacies, it reinforces the broader regulatory direction: the legal pathways for compounding these GLP-1 medications are narrowing across the board.
If finalized, the proposal could significantly impact telehealth firms that have relied on 503B outsourcing facilities to produce these medications at scale.
Outsourcing facilities (503B compounders) face the most immediate and severe impact. If the proposal is finalized, 503B outsourcing facilities will be unable to compound semaglutide, tirzepatide, or liraglutide from bulk drug substances, as neither the 503B bulks list nor the drug shortage list would authorize such activity.
503A compounding pharmacies are not directly affected by the 503B bulks list proposal but remain constrained. The prohibition on compounding drugs that are "essentially a copy" of commercially available products continues to apply. Compounders operating under section 503A should rigorously document medical necessity for any continued compounding of these ingredients and ensure that compounded products are meaningfully different from the commercially available versions.
The litigation risk environment has intensified dramatically. Novo Nordisk and Eli Lilly are actively filing suit and sending cease-and-desist letters to compounders, clinics, and telehealth companies, and multiple state boards of pharmacy are conducting investigations. Compounders that continue to produce these medications without robust documentation of medical necessity risk FDA enforcement actions, state regulatory discipline, and civil litigation from the branded manufacturers.
The public comment period represents a critical window. Interested parties may submit comments electronically through the Federal Register docket by June 29, 2026.
Prescribers should review their current prescribing practices for compounded GLP-1 medications. With the regulatory and litigation landscape shifting decisively against compounding, providers who prescribe or dispense compounded semaglutide or tirzepatide should ensure that each prescription is supported by individualized medical necessity documentation and that compounded products are not "essentially a copy" of commercially available drugs.
Providers face potential liability exposure. Weight loss clinics, medical spas, and telehealth platforms that have relied on compounded GLP-1 products should consult legal counsel regarding their continued operations. Drug manufacturers' cease-and-desist campaigns and lawsuits have targeted not only compounders but also prescribers, clinics, and distributors throughout the supply chain.
We will continue to monitor developments regarding the FDA's 503B bulks list proposal and the broader enforcement landscape. We can help with any questions regarding compliance with the evolving regulatory framework governing compounded GLP-1 medications.
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