How a peptide gets on FDA's 503A bulks list: nomination, PCAC vote, rulemaking

Step 1: Nomination

Pharmacies, trade groups, clinics or anyone else can nominate a bulk drug substance through FDA’s public docket. A nomination should include enough information for FDA to evaluate the substance. Under FDA’s interim policy, nominations made before January 7, 2025 were sorted into Categories 1, 2 or 3 (Category 1, Category 2). Later nominations are not categorized.

A nominator can withdraw. That is what happened to most popular peptides in 2026: their nominations were withdrawn and FDA moved them out of active Category 2 (report).

Step 2: FDA’s evaluation

FDA reviews each substance against the four criteria in 21 CFR 216.23(c):

1. “The physical and chemical characterization of the substance”;
2. “Any safety issues raised by the use of the substance in compounded drug products”;
3. “The available evidence of the effectiveness or lack of effectiveness of a drug product compounded with the substance, if any such evidence exists”; and
4. “Historical use of the substance in compounded drug products,” including peer-reviewed literature.

FDA writes a briefing document for each substance and usually states a position, such as proposing that a substance “NOT be included on the 503A Bulks List.”

Step 3: The PCAC meeting

FDA announces the meeting in the Federal Register and opens a docket. At the meeting, FDA reviewers and the nominators present, the public may speak, and members vote. FDA phrases the question the same way each time. In the December 2024 minutes, for example: “FDA is proposing that CJC-1295 (free base) NOT be included on the 503A Bulks List. Should CJC-1295 (free base) be placed on the list?”

Recent peptide meetings:

Meeting	Peptides	Result
Oct 29, 2024	Ipamorelin, kisspeptin-10, ibutamoren, L-theanine	All rejected (report)
Dec 4, 2024	CJC-1295, AOD-9604, thymosin alpha-1	All rejected (report)
Jul 23-24, 2026	BPC-157, KPV, TB-500, MOTS-c, Semax, Epitalon, emideltide	Six recommended, DSIP rejected (report)
Before end of Feb 2027	LL-37, GHK-Cu, dihexa, Melanotan II, PEG-MGF	Not yet held (report)

Step 4: FDA decides

The vote is advice. FDA’s meeting page says advisory committees “make non-binding recommendations to the FDA.” FDA can follow the committee, go against it, or delay. In October 2026 the Center for Science in the Public Interest asked FDA to reject the July votes because FDA staff had recommended against all seven peptides (report).

Step 5: Rulemaking

To add a substance, FDA publishes a proposed rule, takes public comments and issues a final rule amending 21 CFR 216.23. FDA can also decide by rule not to list a substance; 216.23(b) lists four it has rejected (oxitriptan, piracetam, silver protein mild and tranilast). As of October 19, 2026, the list in 216.23(a) has six substances and no peptides.

Where enforcement discretion fits

FDA can also choose not to enforce the law against certain compounding while it decides. The Category 1 policy works this way. The Interim Access Policy for Compounding Using Certain Peptides, sent to OMB in October 2026, is reported to take the same approach for some peptides (explainer). Enforcement discretion can be changed or withdrawn without rulemaking, which makes it faster and less durable than a listing.