On May 1, 2026, the FDA published a notice (Docket FDA-2018-N-3240) proposing to exclude the three main GLP-1 substances — semaglutide, tirzepatide, and liraglutide — from the "503B bulks list." It's a technical-sounding decision with a very practical effect on how compounded GLP-1s can be made, and the public comment period is open. If access matters to you, this is a place your voice is explicitly invited.
What the 503B bulks list is
"503B outsourcing facilities" are a category of compounder that makes medications in larger volumes under stricter federal oversight than a typical pharmacy. A 503B facility generally cannot compound a drug from a bulk substance unless that substance is on the FDA's "503B bulks list" — a list of substances for which the FDA has found a genuine clinical need. (A separate pathway existed while the brand-name drugs were in official shortage, but those shortages have since ended.)
So whether semaglutide, tirzepatide, and liraglutide appear on this list shapes whether 503B facilities can keep compounding them from bulk.
What the FDA is proposing, and why
After reviewing the nominations it received, the FDA says it did not find sufficient evidence of a clinical need for outsourcing facilities to compound these three drugs from bulk substances, and is proposing to leave them off the list. Under the law, a "clinical need" determination turns on patient safety and medical necessity — for example, whether patients need something the FDA-approved products can't provide.
Supporters of the proposal point to safety and quality concerns with compounded versions. Critics — including some patient and consumer groups — worry about cost and access, since compounded options have been more affordable or available for some people. This guide isn't taking a side; it's pointing you to a decision that's still open and how to weigh in.
Why it matters for access
If finalized as proposed, this would further narrow the legal routes for 503B-compounded GLP-1s. For patients, the real-world questions are about cost and availability of alternatives — which is exactly the kind of access issue where public comment and patient experience carry weight.