FDA proposes to exclude semaglutide, tirzepatide and liraglutide from the 503B bulks list

The FDA proposed leaving semaglutide, tirzepatide and liraglutide off the 503B bulk drug substances list, finding no clinical need for outsourcing facilities to compound them from bulk now that the GLP-1 shortages are resolved. If finalized, the exclusion would close the last routine legal pathway for large-scale compounded GLP-1s and further narrow the supply of non-branded semaglutide and tirzepatide. The FDA took comments on the proposal through mid-2026 and is reviewing them; a final determination had not been published as of this writing.