The FDA compounding fight, explained: Category 2, the 503A lists and the 2026 panel votes

Between March and April 2026, several peptides left Category 2 of the FDA's compounding policy after their nominators withdrew them, and in July an advisory panel voted on seven of them. There seems to be confusion about what is a list, what is a category and what is a vote. We use the FDA's own website and public filings to lay out what has happened.

For laboratory research use only. Not for human or veterinary use. Nothing here is medical advice.

503A, 503B and the bulks lists

Federal law sets up two kinds of compounders. Under section 503A, state-licensed pharmacists and physicians compound. Under section 503B, registered "outsourcing facilities" do.[1][2]

A 503A compounder may use a bulk drug substance only if it meets a USP or NF monograph, is a component of an FDA-approved drug, or appears on "FDA's list of bulk drug substances that can be used in compounding (the 503A bulks list)."[1] That list is a regulation, 21 CFR 216.23. As of October 11, 2026, it names six substances, none of them a peptide. Its last change was in March 2019.[15]

A 503B facility may use a bulk substance only if it is on the 503B bulks list, which covers substances "for which there is a clinical need," or if the drug is on FDA's shortage list.[2]

The interim policy and Categories 1, 2 and 3

While FDA evaluates nominations, an interim policy sorts nominated substances into three categories. FDA's short definitions:[1]

• Category 1: substances that "were nominated with sufficient supporting information for FDA to evaluate them." For these, FDA "does not intend to take action" if the guidance conditions are met.
• Category 2: "FDA has identified significant safety risks relating to the use of these substances in compounding pending further evaluation." For these, FDA "would consider taking action against a compounder."
• Category 3: substances that "were nominated with insufficient supporting information for FDA to evaluate them."

FDA's 503A page says the revised guidance "states the agency does not intend to place bulk drug substances nominated on or after January 7, 2025, into these categories."[1] A category is an enforcement policy, not a listing decision.

Category 2 and peptides

FDA's Category 2 table, as archived in a copy captured March 5, 2026, gave September 29, 2023 as the date fourteen 503A entries were added. They included BPC-157, Emideltide (DSIP), Epitalon, KPV, MOTs-C, Semax (heptapeptide) and "Thymosin beta-4, fragment (LKKTETQ)," which FDA calls TB-500.[4]

The live FDA page, dated April 22, 2026, now has a second table: "Bulk drug substances nominated but withdrawn." FDA describes it as substances "previously in category 2" that "were withdrawn by the nominators." BPC-157 and the other six peptides above are in it, with FDA's risk notes still attached.[3] The page does not state the date of each move.

Withdrawal did not end FDA's review. In its July 2026 briefing document, FDA writes of BPC-157: "The nominations were withdrawn and FDA is evaluating the substances at its discretion." It then states that "FDA has decided to evaluate both on its own initiative," meaning the free base and the acetate.[11] FDA's briefing introduction says it is "electing to proceed" with presenting the withdrawn peptides to its advisory committee.[10]

Kisspeptin-10 remains in 503A Category 2, dated September 29, 2023.[3][5]

The advisory committee

The Pharmacy Compounding Advisory Committee (PCAC) advises FDA on bulks-list decisions. FDA's own page says advisory committees make "non-binding recommendations" and that FDA "is not legally bound" to follow them.[8]

2024 meetings

In each vote below, FDA had proposed not listing the substance. The committee then voted on whether each substance should be placed on the list. The counts are from FDA's final summary minutes.[6][7]

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July 23-24, 2026

FDA's meeting page lists seven substance families, each as a free base and an acetate.[8] On July 23, the committee took up BPC-157, KPV, TB-500 and MOTs-C. On July 24, it took up Emideltide (DSIP), Semax and Epitalon. Each was evaluated against specific uses named on FDA's page. FDA's question sheet calls for two votes per family, one on the free base and one on the acetate.[9]

FDA staff's position. All seven briefing documents reach the same conclusion. For BPC-157, "a balancing of the criteria weighs against" listing either form. FDA writes, "we propose not adding BPC-157 (free base) or BPC-157 acetate to the 503A Bulks List."[11] The other six documents, TB-500 included, end with the same "we propose not adding" sentence.[12]

The votes. FDA has posted no minutes, transcript or vote tallies for this meeting. Its page, "Content current as of 08/06/2026," lists only pre-meeting materials and FDA presentations. It was unchanged when fetched October 11, 2026.[8]

The counts below are as reported by two law firms, on July 24 and July 27, 2026, not from an FDA record.[19][20] One of them reports that for BPC-157, KPV and TB-500 the panel reached the same 8-6-1 count "separately for both the free base and the acetate forms."[19] ABC News reported the same BPC-157 count on July 23 and notes the vote "is non-binding and still needs sign-off from the FDA."[13]

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Until the FDA posts its minutes, these remain reported counts.

What happens next

No rule yet. As of October 11, 2026, the Federal Register shows no proposed or final rule amending the 503A bulks list after September 5, 2019.[14] FDA's 503A page still says, of that 2019 proposal, "the agency will issue a final regulation."[1]

A court filing with a date. In Evexias Medical Centers, PLLC v. FDA (N.D. Tex., No. 4:24-cv-00293-O), the only remaining claim was that FDA had delayed deciding on four substances: AOD-9604, CJC-1295, ipamorelin acetate and Thymosin Alpha-1.[16] In a joint status report filed August 18, 2025, FDA said that "by the end of February 2027, the agency expects to submit" a final rule on those four to the Office of the Federal Register. A footnote allows for delay from events "outside the reasonable control of FDA."[16] This filing does not cover BPC-157 or the other 2026 peptides.

The 503B side

The 503B bulks list page, "Updated August 21, 2023," lists five substances as included. None is a peptide.[17] Category 2 also has 503B entries. GHRP-2, GHRP-6 and Ipamorelin acetate are listed there with the date September 29, 2023.[3]

Enforcement shows how the 503B rules apply. In a warning letter dated January 20, 2026, FDA told GenoGenix LLC, a registered outsourcing facility: "Drug products compounded using 5-Amino-1MQ and NAD+ are not eligible for the exemptions provided by section 503B." The reason given is that neither substance appears on the 503B bulks list or the shortage list.[18] The same letter states that "Products such as Thymosin Beta-4 are unapproved new drugs" under section 505.[18]

What this does not mean

• A category, a list entry and a committee vote are all regulatory status. Not one of them tells you what a compound does in a person.
• A list entry is not approval either. FDA's BPC-157 briefing document says neither form "is a component of an FDA-approved drug,"[11] and the 503A bulks list in 21 CFR 216.23 contains none of the peptides named here.[15]
• Leaving Category 2 is not approval. The FDA still keeps its risk notes next to each withdrawn entry.[3]
• A committee vote is not an FDA ruling. As of October 11, 2026, FDA has posted no vote record for July 2026 and has published no rule.[8][14]

For laboratory research use only. Not for human or veterinary use, diagnostic, or therapeutic purposes.

Sources (fetched October 11, 2026)

1. FDA, "Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act" (content current as of 05/14/2026): https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503a-fdc-act
2. FDA, "Bulk Drug Substances Used in Compounding Under Section 503B of the FD&C Act" (content current as of 01/07/2025): https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503b-fdc-act
3. FDA, "Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks" (content current as of 04/22/2026): https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
4. Internet Archive copy of source 3, captured March 5, 2026 (page content current as of 07/08/2025): https://web.archive.org/web/20260305132226/https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
5. FDA, categories of bulk drug substances nominated under 503A (updated May 14, 2026): https://www.fda.gov/media/94155/download
6. FDA, Final Summary Minutes, PCAC meeting of October 29, 2024: https://www.fda.gov/media/185412/download
7. FDA, Final Summary Minutes, PCAC meeting of December 4, 2024: https://www.fda.gov/media/185642/download
8. FDA, July 23-24, 2026 PCAC meeting page (content current as of 08/06/2026): https://www.fda.gov/advisory-committees/advisory-committee-calendar/july-23-24-2026-meeting-pharmacy-compounding-advisory-committee-07232026
9. FDA, PCAC questions, July 23-24, 2026: https://www.fda.gov/media/193711/download
10. FDA, PCAC briefing document introduction, July 23-24, 2026: https://www.fda.gov/media/193342/download
11. FDA, PCAC briefing document, BPC-157-related bulk drug substances: https://www.fda.gov/media/193343/download
12. FDA, PCAC briefing documents: Emideltide https://www.fda.gov/media/193344/download ; Epitalon https://www.fda.gov/media/193345/download ; KPV https://www.fda.gov/media/193346/download ; MOTS-c https://www.fda.gov/media/193347/download ; Semax https://www.fda.gov/media/193348/download ; TB-500 https://www.fda.gov/media/193349/download
13. ABC News, "FDA advisory committee votes to add popular peptide BPC-157 to drug compounding list," July 23, 2026: https://abcnews.com/Health/fda-advisory-committee-votes-add-popular-peptide-bpc/story?id=134913891
14. Federal Register, FDA rules and proposed rules containing "503A," 2019 to October 11, 2026: https://www.federalregister.gov/documents/search?conditions%5Bagencies%5D%5B%5D=food-and-drug-administration&conditions%5Bterm%5D=%22503A%22&conditions%5Btype%5D%5B%5D=RULE&conditions%5Btype%5D%5B%5D=PRORULE
15. eCFR, 21 CFR 216.23 (version history checked October 11, 2026): https://www.ecfr.gov/current/title-21/chapter-I/subchapter-C/part-216/subpart-B/section-216.23
16. Evexias Medical Centers, PLLC v. FDA, N.D. Tex. No. 4:24-cv-00293-O, ECF 38 (filed March 13, 2025) and ECF 46, Joint Status Report (filed August 18, 2025): https://storage.courtlistener.com/recap/gov.uscourts.txnd.388121/gov.uscourts.txnd.388121.38.0.pdf ; https://storage.courtlistener.com/recap/gov.uscourts.txnd.388121/gov.uscourts.txnd.388121.46.0.pdf
17. FDA, "503B Bulk Drug Substances List" (updated August 21, 2023; content current as of 05/16/2024): https://www.fda.gov/drugs/human-drug-compounding/503b-bulk-drug-substances-list
18. FDA, Warning Letter to GenoGenix LLC, WL 718739, January 20, 2026 (content current as of 03/03/2026): https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/warning-letters/genogenix-llc-718739-01202026
19. Hyman, Phelps & McNamara, FDA Law Blog, "PEPTIDE-L WAVE! PCAC Approves Four Bulk Drug Substances for the 503A List," July 24, 2026: https://www.thefdalawblog.com/2026/07/peptide-l-wave-pcac-approves-four-bulk-drug-substances-for-the-503a-list/
20. McDermott Will & Schulte, "Bulk-list bound? PCAC backs majority of peptides in two-day public meeting," July 27, 2026: https://www.mcdermottlaw.com/insights/bulk-list-bound-pcac-backs-majority-of-peptides-in-two-day-public-meeting/