On April 30, 2026, the FDA published a notice in the Federal Register proposing to exclude semaglutide, tirzepatide, and liraglutide from the 503B Bulks List — the list of bulk drug substances eligible for use by FDA-registered 503B outsourcing facilities. The notice opens a 60-day public comment period closing on June 29, 2026.
If finalized, the rule would constrain the supply of compounded GLP-1 medications routed through 503B outsourcing facilities. The 503A patient-specific compounding pathway is explicitly unaffected: 503A pharmacies derive their authority from a different section of the Federal Food, Drug, and Cosmetic Act and are not governed by the 503B Bulks List.
Industry impact analysis suggests the most affected providers are those routing the majority of their compounded supply through 503B facilities for cost reasons. Providers with established 503A relationships or dual-pathway disclosure (NexLife being the cleanest example in our 2026 ranking) are likely to be less affected.