FDA's 2025-2026 review of peptides for compounding

Between April and October 2026, FDA's handling of several widely sold unapproved peptides moved further than at any point since 2023: nominations were withdrawn, entries left FDA's active Category 2 table, and an advisory committee voted on seven peptides ^4,6. None of that has yet changed the 503A bulks list itself ⁵. This article sets out what happened and when, and what has stayed the same, as of 22 October 2026. It is information about a regulatory process, not legal advice; the legality guide covers the wider framework.

The legal frame: 503A, 503B and the bulks lists

Section 503A covers drugs compounded by a licensed pharmacist in a state-licensed pharmacy or a federal facility, or by a licensed physician ¹. A 503A compounder may use a bulk drug substance only if it complies with a USP or NF monograph, is a component of an FDA-approved drug, or appears on FDA's 503A bulks list ². Bulk substances must also come with a valid certificate of analysis and be made by an FDA-registered establishment ². Section 503B outsourcing facilities follow a separate rule: they may not compound from a bulk substance unless it is on the list of substances with a clinical need or the finished drug is on FDA's drug shortage list ³. Compounded drugs are not FDA-approved, and FDA does not verify their safety, effectiveness or quality before they are marketed ¹².

Categories 1, 2 and 3

Because the 503A list is built through rulemaking, FDA uses an interim policy that sorts nominated substances into three categories ². FDA does not intend to act against compounders who use Category 1 substances when the guidance conditions are met ². Category 2 holds substances for which FDA has identified significant safety risks, and FDA would consider action against compounders who use them under its general enforcement policies ². Category 3 substances were nominated with insufficient supporting information ². FDA has said it does not intend to place substances nominated on or after 7 January 2025 into these categories ². The list itself rests on a February 2019 final rule that placed six substances on it and a September 2019 proposed rule after which, FDA says, a final regulation will be issued ².

Spring 2026: withdrawn nominations and a new table

FDA's Category 2 page, updated 22 April 2026, now carries a separate table of substances that were previously in Category 2 and whose nominations were withdrawn by the nominators ⁴. That table has 17 entries: AOD-9604, BPC-157, cathelicidin LL-37, CJC-1295, dihexa acetate, emideltide (DSIP), epitalon, GHK-Cu for injectable routes, ipamorelin acetate, KPV, PEG-MGF, melanotan II, MOTs-C, selank acetate, semax, the thymosin beta-4 fragment known as TB-500, and thymosin alpha-1 ⁴. FDA still prints its safety concerns beside each one; for BPC-157 it says it lacks sufficient information to know whether the drug would cause harm when administered to humans ⁴. Ipamorelin acetate appears in both tables because it remains in Category 2 under the 503B interim policy ⁴. The active Category 2 table still lists GHRP-2 and GHRP-6 (503B), ibutamoren mesylate (503A and 503B), ipamorelin acetate (503B) and kisspeptin-10 (503A) ⁴.

Leaving the active Category 2 table is not the same as entering Category 1. FDA's 503A categories document, updated 14 May 2026, does not list BPC-157, KPV, TB-500, MOTs-C, semax, epitalon or emideltide in any category ⁵.

The July 2026 advisory committee meeting

On 16 April 2026, FDA published a Federal Register notice announcing a meeting of the Pharmacy Compounding Advisory Committee (PCAC) on 23 and 24 July 2026 to discuss bulk substances nominated for the 503A list ¹. The committee advises FDA on scientific, technical and medical issues in 503A and 503B compounding ¹¹. Its recommendations are non-binding: FDA generally follows them but is not legally bound to do so ⁶. FDA asked members to vote separately on the free base and the acetate form of each peptide ⁷.

FDA reviewed each peptide only for the uses named by its nominators ⁶:

• 23 July: BPC-157 (ulcerative colitis), KPV (wound healing and inflammatory conditions), TB-500 (wound healing) and MOTs-C (obesity and osteoporosis) ⁶.
• 24 July: emideltide, also called delta sleep-inducing peptide (opioid withdrawal, chronic insomnia and narcolepsy), semax (cerebral ischemia, migraine and trigeminal neuralgia) and epitalon (insomnia) ⁶.

FDA's own reviewers argued against the nominations. For BPC-157, the briefing document said the substance is not well characterized physicochemically, that safety and immunogenicity information is lacking, that evidence of effectiveness in ulcerative colitis is insufficient, and that approved drugs exist for the condition; FDA therefore proposed not adding either form to the list ⁸. For epitalon, FDA's briefing document said a search of the published literature did not retrieve publications discussing efficacy in patients with insomnia, and concluded that a balancing of the criteria weighed against placing either form on the list ¹⁴.

How the committee voted

The committee recommended six of the seven peptides it discussed, according to The BMJ's report of the meeting ⁹. FDA's meeting page posts the agenda, questions, presentations and briefing documents but no minutes or vote results as of 22 October 2026 ⁶, so this page does not report per-peptide tallies. A July-August 2026 analysis in the International Journal of Pharmaceutical Compounding examines the proposed uses of these peptides and the concerns raised during the review ¹³.

What happens next

A favourable vote does not add a substance to the 503A list. FDA says it addresses nominated substances through notice-and-comment rulemaking ². As of 22 October 2026, FDA's categories document did not place any of the seven peptides in Category 1 ⁵. FDA has also announced that the committee will meet again before the end of February 2027 to discuss five more substances for the 503A list: cathelicidin LL-37, GHK-Cu, dihexa acetate, melanotan II and PEG-MGF ¹⁰. Both the July meeting and the planned one concern the 503A list ^6,10.

What has changed and what has not

• Changed: 17 entries, most of them peptides, moved to FDA's table of withdrawn nominations ⁴.
• Changed: the PCAC recommended six of the seven peptides it discussed for the 503A list ⁹.
• Not changed: none of the seven is on the 503A list or in Category 1 ⁵.
• Not changed: compounded drugs are not FDA-approved, and committee recommendations are non-binding ^6,12.
• Not changed: 503B outsourcing facilities remain limited to the 503B list or the drug shortage list ³.
• Not changed: GHRP-2 and GHRP-6 (503B), ibutamoren (503A and 503B), kisspeptin-10 (503A) and ipamorelin (503B) remain in Category 2 ⁴; under 503A, GHRP-2 and GHRP-6 are in Category 3 ⁵.