FDA's Category 2 peptide list now names one peptide for pharmacies, kisspeptin-10, after 17 withdrawals

FDA's Category 2, its list of compounding ingredients that the agency says raise significant safety risks, now names one peptide for state-licensed pharmacies: kisspeptin-10. In September 2023 FDA added 19 substances to it, all but one of them peptides or peptide derivatives, including BPC-157, TB-500, CJC-1295 and ipamorelin.

Seventeen of those entries have since left, and none left because FDA changed its view of the risk. In each case, FDA's own record says the nomination that had put the substance up for compounding was withdrawn: five in September 2024, and twelve on April 22, 2026, among them BPC-157, TB-500, KPV, MOTS-c, semax and epitalon.

Category 2 is often called a ban, and leaving it is often called legalization. It is neither. It is a category in an interim enforcement policy for compounding pharmacies. A peptide that leaves it does not become lawful to compound, and it never governed peptides sold as chemicals for laboratory research.

What FDA's Category 2 means for a peptide

Section 503A of the Federal Food, Drug, and Cosmetic Act lets a state-licensed pharmacy compound a drug for an individual prescription without FDA approval. It may use only bulk substances that have a pharmacopeia monograph, are components of approved drugs, or appear on the 503A bulks list, which FDA makes by regulation. Few substances are on that list. While it evaluates the rest, FDA sorts nominated substances into three categories under an interim guidance.

FDA's three categories for substances nominated for the 503A bulks list

Category	FDA's description	What FDA says it will do
1	Nominated with enough information to evaluate; may be eligible for the list	Does not intend to act against compounders using them, if the guidance's conditions are met
2	Nominated with enough information, but FDA has identified significant safety risks	Would consider taking action under its general enforcement policies
3	Nominated without enough information to evaluate	Would consider taking action under its general enforcement policies

The categories are a statement of FDA's enforcement intentions, not a regulation. Only Category 1 carries any promise of forbearance. A substance in Category 2 is in the same position as any other substance that is not on the 503A list, with one difference: FDA has said in public why it is concerned. In the agency's words, if it adds a substance to Category 2 it will publish the safety information describing the risks on FDA.gov.

The system is closing. FDA's 503A page says a revised guidance states the agency does not intend to place bulk drug substances nominated on or after January 7, 2025, into these categories. No substance nominated since then will be placed in Category 2.

Every peptide FDA has placed in Category 2 for pharmacies

FDA's 503A category list of November 2, 2021 named four substances in Category 2, none of them a peptide. The version of September 29, 2023 added 19. The table below gives every peptide among them and what has happened to each, from FDA's own category documents and advisory committee minutes.

Peptides in FDA's 503A Category 2, added September 29, 2023, as of November 3, 2026

Peptide	Left Category 2	Advisory committee
AOD-9604	September 27, 2024, nomination withdrawn	December 4, 2024: against listing, 0⁠–⁠12
BPC-157	April 22, 2026, nominations withdrawn	July 23, 2026: recommended for listing
Cathelicidin LL-37	April 22, 2026, nomination withdrawn	FDA intends to consult it by the end of February 2027
CJC-1295	September 27, 2024, nominations withdrawn	December 4, 2024: against listing all five forms, 0⁠–⁠13 or 1⁠–⁠12
Dihexa acetate	April 22, 2026, nomination withdrawn	FDA intends to consult it by the end of February 2027
Emideltide (DSIP)	April 22, 2026, nominations withdrawn	July 24, 2026: not recommended
Epitalon	April 22, 2026, nominations withdrawn	July 24, 2026: recommended for listing
GHK-Cu, for injectable routes of administration	April 22, 2026, nominations withdrawn	FDA intends to consult it by the end of February 2027
Ipamorelin acetate	September 27, 2024, nominations withdrawn; still in Category 2 for outsourcing facilities	October 29, 2024: against listing, 0⁠–⁠12 with one abstention
Kisspeptin-10	Still in Category 2	October 29, 2024: against listing, 0⁠–⁠11
KPV	April 22, 2026, nomination withdrawn	July 23, 2026: recommended for listing
Melanotan II	April 22, 2026, nominations withdrawn	FDA intends to consult it by the end of February 2027
Mechano growth factor, pegylated (PEG-MGF)	April 22, 2026, nomination withdrawn	FDA intends to consult it by the end of February 2027
MOTS-c	April 22, 2026, nomination withdrawn	July 23, 2026: recommended for listing
Selank acetate (TP-7)	September 27, 2024; the nominator meant a different substance	None announced
Semax (heptapeptide)	April 22, 2026, nominations withdrawn	July 24, 2026: recommended for listing
Thymosin alpha-1	September 27, 2024, nomination withdrawn	December 4, 2024: against listing, 4⁠–⁠17
TB-500 (thymosin beta-4 fragment, LKKTETQ)	April 22, 2026, nomination withdrawn	July 23, 2026: recommended for listing

The 19th substance added in 2023, ibutamoren mesylate, is not a peptide and remains in Category 2. The other substances in the category today are cesium chloride, domperidone, germanium sesquioxide and quinacrine hydrochloride for one route, none of them peptides.

FDA's stated concerns about the Category 2 peptides

FDA's reasons are published, peptide by peptide, on its page of Category 2 safety risks, and they are strikingly uniform. Nearly every entry opens with the same two concerns, immunogenicity and characterization. For BPC-157 the agency wrote that compounded products may pose risk for immunogenicity for certain routes of administration and may have complexities with regard to peptide-related impurities and active pharmaceutical ingredient (API) characterization.

The second concern is a laboratory one. Peptide-related impurities are the truncated, deleted, oxidized and otherwise modified sequences that synthesis leaves behind, which reversed-phase HPLC separates and mass spectrometry identifies. Related substances explains how they are measured, and What HPLC does not see covers what a purity figure leaves out. FDA adds a structural point for two of these peptides: GHRP-2 and ipamorelin contain unnatural amino acids, which, in the agency's words, add to the complexity of peptide characterization.

The third concern, repeated across most entries, is the absence of evidence. For KPV, MOTS-c, PEG-MGF, dihexa and TB-500, FDA wrote that it had not identified any human exposure data at all. For BPC-157, epitalon, semax and emideltide, it wrote that it lacks sufficient information to know whether the drug would cause harm. The agency was describing gaps in the record more often than findings of harm.

How 17 peptide entries left Category 2

A substance is in a category because someone nominated it for the 503A list. When the nomination is withdrawn, the substance is no longer under evaluation, and FDA takes it out of the category. That is the reason FDA gives for every peptide that has left, in the same form of words: it has been removed from category 2 because the nominations were withdrawn by the nominators. Selank is the exception; FDA says its nominator had meant to nominate a different substance.

The withdrawals came in two waves, and each was followed by a scheduled advisory committee meeting.

• September 27, 2024. AOD-9604, CJC-1295, ipamorelin, thymosin alpha-1 and selank left. FDA took ipamorelin to its Pharmacy Compounding Advisory Committee on October 29, 2024, and AOD-9604, CJC-1295 and thymosin alpha-1 on December 4, 2024. The committee voted against listing every one of them.
• April 15 and 22, 2026. On April 15 FDA posted notice that twelve substances will be removed from category 2 after seven calendar days, and the revised list of April 22 dropped them. FDA scheduled seven for the committee on July 23 and 24 and said it would consult on the other five before the end of February 2027. In July the committee recommended six, BPC-157, TB-500, KPV, MOTS-c, semax and epitalon, against FDA staff advice, and rejected emideltide.

Leaving Category 2 this way authorizes nothing. A substance with no live nomination is in no category at all, so not even the Category 1 forbearance applies. What changed the position of the six recommended peptides was a separate step. On October 30, 2026, the Department of Health and Human Services published a notice that it will not take enforcement action against licensed pharmacies and physicians compounding them under stated conditions while FDA writes a rule. Our piece on the docket sets out those conditions.

The peptides still in Category 2

For state-licensed pharmacies under section 503A, one: kisspeptin-10, in Category 2 since September 29, 2023, and voted down for the 503A list by the advisory committee on October 29, 2024, 11 to 0.

FDA keeps a parallel system for outsourcing facilities under section 503B, and three peptides remain in its Category 2: GHRP-2 (for injectable and nasal routes of administration), GHRP-6 and ipamorelin acetate, each since September 29, 2023. Ipamorelin is the only peptide on both sides of the record, withdrawn from the 503A category in 2024 and still in the 503B one.

A few peptides sit in Category 1, where FDA does not intend to act against compounders who meet the guidance's conditions. FDA's list of May 14, 2026 includes vasoactive intestinal peptide and GHK-Cu (except for injectable routes of administration). FDA restored GHK-Cu to Category 1 after a nominator clarified on May 5 that it had meant to withdraw only part of its nomination.

What Category 2 means for research peptides

Category 2 is a list of compounding ingredients. It governs what FDA says it will do about state-licensed pharmacies and physicians who compound with a bulk substance, and it has no bearing on a peptide sold and bought as a chemical for laboratory research. A research-labeled vial of BPC-157 was not in Category 2 in 2025, and it was not released from anything in April 2026. Its legal status depends on intended use, as Are research peptides legal in the US? sets out.

The category still says something worth reading for a laboratory. FDA's stated concerns, impurities and characterization, are the ones a certificate of analysis is meant to answer, and the agency's July 2026 briefing documents found the nominated peptides not well characterized for identity, purity and quality. Reading a certificate of analysis covers what to look for.

What to watch on FDA's peptide categories

• Five more peptides before the advisory committee. FDA says it intends to consult the committee on cathelicidin LL-37, dihexa acetate, GHK-Cu, melanotan II and PEG-MGF before the end of February 2027.
• Rulemaking on the six recommended peptides. Only a final rule adding them to the 503A bulks list makes compounding them lawful under section 503A. Until then, the HHS notice is enforcement discretion.
• The HHS docket. Comments on the HHS peptide policy close November 13, 2026, on docket HHS-OASH-2026-0496.
• Kisspeptin-10. The only peptide left in the 503A category, and already voted down by the committee in 2024. Its status now turns on rulemaking, and FDA's 503A page lists no rule on it.

Frequently asked questions

What are Category 2 peptides?

Peptides that FDA, while evaluating them for the 503A bulks list, placed in Category 2 of its interim compounding policy because it identified significant safety risks. FDA added most of them on September 29, 2023. As of November 2026, kisspeptin-10 is the only peptide still in the 503A Category 2.

Which peptides were removed from Category 2?

AOD-9604, CJC-1295, ipamorelin, thymosin alpha-1 and selank on September 27, 2024; BPC-157, TB-500, KPV, MOTS-c, semax, epitalon, emideltide (DSIP), cathelicidin LL-37, dihexa acetate, GHK-Cu (for injectable routes of administration), melanotan II and PEG-MGF on April 22, 2026. In every case but selank, FDA says the nomination was withdrawn.

What is the difference between Category 1 and Category 2 peptides?

FDA does not intend to act against compounders using Category 1 substances under the guidance's conditions. For Category 2 substances, FDA has identified significant safety risks and would consider taking action. Neither category is the 503A bulks list itself.

Is Category 2 a ban on peptides?

No. It is a category in FDA's interim enforcement policy for compounding, not a regulation. Leaving it does not make a peptide lawful to compound, and it has no bearing on peptides sold as chemicals for laboratory research.

Is BPC-157 still in Category 2?

No. FDA removed it on April 22, 2026, after its nominations were withdrawn. The advisory committee recommended it for the 503A bulks list in July 2026, and HHS said on October 30, 2026 that it will not act against licensed pharmacies compounding it under stated conditions. It is not on the 503A bulks list. This is not legal advice.

Sources & Further Reading

1. Food and Drug Administration. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act (category list). Versions updated November 2, 2021; September 29, 2023; May 20, 2024; September 27, 2024; April 15, 2026; April 22, 2026; May 14, 2026. Earlier versions read in the Internet Archive's copies of fda.gov/media/94155/download.
2. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Content current as of April 22, 2026; earlier versions read in the Internet Archive, September 2024 to April 21, 2026.
3. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act. Content current as of May 14, 2026.
4. Food and Drug Administration. Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the Federal Food, Drug, and Cosmetic Act. Guidance for industry, with Revision 2 (draft published December 7, 2023).
5. Food and Drug Administration, Center for Drug Evaluation and Research. Final Summary Minutes of the Pharmacy Compounding Advisory Committee Meeting, October 29, 2024.
6. Food and Drug Administration, Center for Drug Evaluation and Research. Final Summary Minutes of the Pharmacy Compounding Advisory Committee Meeting, December 4, 2024.
7. Food and Drug Administration. Pharmacy Compounding Advisory Committee; Notice of Meeting. 91 FR 20465, April 16, 2026, FR Doc. 2026-07361, Docket FDA-2025-N-6895.
8. Pharmacy Compounding Advisory Committee meeting, July 23⁠–⁠24, 2026; FDA briefing documents, Docket FDA-2025-N-6895.
9. Department of Health and Human Services. Enforcement Discretion Policy Regarding 503A Compounding Using Certain Peptide Bulk Drug Substances; notice of availability. 91 FR 68526, October 30, 2026, FR Doc. 2026-22192, Docket HHS-OASH-2026-0496.
10. Federal Food, Drug, and Cosmetic Act §§ 503A, 503B; 21 U.S.C. §§ 353a, 353b.

Cosmic Peptides. (2026, November 3). FDA's Category 2 peptide list now names one peptide for pharmacies, kisspeptin-10, after 17 withdrawals. Cosmic Peptides Research Library. Retrieved November 3, 2026, from https://cosmicpeptides.com/research/compliance/fda-category-2-peptides

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  title        = {FDA's Category 2 peptide list now names one peptide for pharmacies, kisspeptin-10, after 17 withdrawals},
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  urldate      = {2026-11-03},
  note         = {Last reviewed 2026-11-03}
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