FDA proposes excluding semaglutide, tirzepatide and liraglutide from 503B bulks list

The Food and Drug Administration on April 30 proposed excluding semaglutide, tirzepatide and liraglutide from the 503B bulks list after concluding there is no clinical need for large-scale compounders to make the drugs from bulk substances.

“The U.S. Food and Drug Administration today announced it is proposing to exclude semaglutide, tirzepatide, and liraglutide on the 503B bulks list,” the agency said in a press release Thursday. FDA also said it reviewed the nominations it received and “did not identify a clinical need” and did not find sufficient evidence to include the three substances on the list.

The move matters because the drugs are the active ingredients in some of the best-known diabetes and obesity treatments on the market. Semaglutide is used in Novo Nordisk’s Ozempic and Wegovy. Tirzepatide is the active ingredient in Eli Lilly’s Mounjaro and Zepbound. Liraglutide is used in Novo Nordisk’s Victoza and Saxenda.

If the proposal is finalized, it would further narrow a major legal pathway for 503B outsourcing facilities — FDA-registered large-scale compounders — to make versions of those drugs from bulk active ingredients.

Under federal law, outsourcing facilities generally cannot compound from bulk drug substances unless the substance appears on the FDA’s 503B bulks list or the finished drug is on the FDA drug shortage list at the time of compounding, distribution and dispensing. That makes the 503B list a key gatekeeper for whether those facilities can lawfully use bulk ingredients in compounded drugs.

A Federal Register notice for the proposal was filed April 30 and is scheduled for publication May 1. FDA said it will accept public comments through June 29 before making a final determination.

“When FDA-approved drugs are available, outsourcing facilities cannot lawfully compound using bulk drug substances unless there is a clear clinical need,” FDA Commissioner Marty Makary, M.D., M.P.H., said in the agency’s press release.

The practical effect, if FDA finalizes the action, would be limited but significant. Outsourcing facilities would not be able to lawfully use bulk semaglutide, tirzepatide or liraglutide to compound drugs unless the relevant approved drug is on the FDA shortage list or the substance is later added to the 503B bulks list. The proposal does not amount to an immediate blanket ban on all compounding of those medicines, and the FDA materials released Thursday do not say the agency is launching immediate new enforcement before the comment period ends.

The proposal is the latest step in the FDA’s broader tightening of the rules around compounded GLP-1 drugs. The agency removed tirzepatide from the shortage list on Oct. 2, 2024, and removed semaglutide from the shortage list on Feb. 21, 2025. Those shortage-list decisions already narrowed compounding of the two blockbuster drugs and led to litigation by the Outsourcing Facilities Association and others.

Federal district court judges denied requests for preliminary injunctions in March and April 2025, leaving the FDA’s shortage-list actions in place while appeals continued.

Thursday’s announcement does not settle the issue yet. It starts a public comment process on whether semaglutide, tirzepatide and liraglutide should be excluded from the 503B bulks list for outsourcing facilities. FDA said it will review the comments it receives before deciding whether to make the exclusions final.