Where FDA Got Its Peptide Chemistry: Commercial Websites, in All Eleven Evaluations

Published September 7, 2026

Between October 2024 and July 2026, FDA published eleven scientific evaluations of individual peptides, prepared for its Pharmacy Compounding Advisory Committee. Read for their footnotes instead of their conclusions, all eleven share a feature nobody has reported: when the agency needed a structure, a molecular weight, a melting point or a certificate of analysis, it repeatedly cited a commercial product page. Sellers' catalogues, chemical suppliers' listings, a safety data sheet, and in one case a clinic's blog post. In nine of the eleven, FDA also records why: the people who asked for the substance to be listed submitted no certificate of analysis at all. This record sets out what the agency cited, in its own words, and then tests the two readings a page like this invites — that a citation is a form of approval, or that it is a warning sign. Neither survives the check.

What these documents are

Under section 503A of the Federal Food, Drug, and Cosmetic Act, a substance can be compounded by a pharmacy if it appears on a list FDA maintains. Members of the public nominate substances for that list. Before the Pharmacy Compounding Advisory Committee votes, FDA staff write an evaluation of each one — chemistry, safety, effectiveness, and historical use.

Eleven peptide evaluations have been published. Four were prepared for meetings in late 2024, seven for the meeting of July 23–24, 2026. We have written separately about what the 2024 votes decided, about the 2026 meeting, and about what FDA could not verify in two of the individual evaluations. This record is about something none of those cover: the sources.

Every document named below was downloaded from fda.gov and read in full for this record. Each is linked at the bottom.

Where the chemistry came from

Each evaluation carries its own date, which is generally several weeks or months before the meeting it was written for. The commercial sources are named here as FDA names them.

Some of those names are ordinary research-reagent suppliers of the sort any university laboratory buys from — Cayman Chemical, Tocris, LKT Labs, MedChemExpress. Others are retail peptide sellers of exactly the kind FDA's compliance office writes warning letters to. Both categories appear, side by side, footnoted the same way.

One example shows the pattern completely. In the BPC-157 evaluation, FDA reports the compound's melting point, molecular formula and a molecular weight of 1,419.5 g/mol, and footnotes all of it to a single ChemicalBook catalogue entry, accessed June 26, 2024. The same paragraph then explains why the agency was working from a catalogue: neither nomination package included a certificate of analysis for the substance. FDA states it again later in the same document — There is no CoA for BPC-157 (free base) in either of the nomination packages.

Why the agency went to commercial websites

FDA says so itself, in a footnote to the AOD-9604 evaluation:

The existence of a supplier of BDS may be relevant to FDA's characterization analysis because it indicates that consistent production of the BDS according to a standard may be possible. BDSs with suppliers are also frequently accompanied by COAs associated with their production, which can help FDA to identify and characterize BDSs.

"BDS" is bulk drug substance — the raw material a pharmacy would compound with. The reasoning is not careless. If a substance has a supplier, someone is making it to a written standard, and that standard usually comes with paperwork. Where the nomination had none, the supplier's paperwork was the best characterization data in existence.

And in most of these cases the nomination had none. Nine of the eleven evaluations state in FDA's own words that no certificate of analysis for the free-base substance was submitted. The wording varies slightly; the finding does not:

• Ipamorelin — Because there is no CoA for ipamorelin (free base) in the nomination packages, we conducted literature searches
• CJC-1295 — There was no CoA for CJC-1295 (free base) in the nominations.
• Thymosin alpha-1 — There was no CoA for Ta1 (free base) in the nomination package.
• BPC-157 — There is no CoA for BPC-157 (free base) in either of the nomination packages.
• Epitalon — There were no CoAs for epitalon (free base) in the nomination packages.
• KPV — There is no CoA for KPV (free base) in the nomination.
• MOTS-c — There is no CoA available for MOTS-c (free base) in the nomination.
• Semax — There is no CoA for semax (free base) in the nomination.
• TB-500 — No CoA for TB-500 (free base) was submitted in the nomination package.

The two exceptions were checked directly, not counted by absence, because a missing sentence is not evidence of a present document. Both AOD-9604 and emideltide did have nominator-supplied certificates — and both of those certificates contradicted themselves on the face of the page. For AOD-9604, FDA records that the nominated substance was the free base but the BDS in the accompanying Certificate of Analysis (CoA) is AOD-9604 acetate, while the identifiers printed on that certificate were the free base's. For emideltide, The chemical name provided in CoA by the nominator does not correspond to the emideltide. So of eleven evaluations, nine had no certificate and the two that had one had a certificate that disagreed with itself.

"Example of a CoA" is doing exact work

The figure captions matter, and FDA chose them carefully. Where the agency reproduces a certificate it found on a commercial site, the caption is not "the certificate of analysis" — it is Example of a CoA for BPC-157, Example of a CoA for Epitalon (Free Base), Example of a Certificate of Analysis for KPV (Free Base), Example of a CoA for Semax, Example of CoA for TB-500 (Free Base). It is an illustration of what documents in this market typically contain, not an authenticated record of a particular batch.

And in every instance, the sentence around the figure says what the certificate does not establish. For epitalon: There were no CoAs for epitalon (free base) in the nomination packages. We conducted literature searches and found that CoAs for epitalon (free base) only contain purity testing. For TB-500, the certificate FDA located includes only appearance, identity by Liquid Chromatography-Mass Spectrometry (LCMS) and high-performance liquid chromatography (HPLC) and peptide purity. However, assay, impurities, bacterial endotoxins, and aggregates are not tested or controlled for TB-500 (free base). For KPV, FDA found most of CoA for KPV (free base) only contains purity testing result.

That is the same finding our own reference pages reach from the analytical side: a purity number is a narrower statement than it looks, and a certificate is only as informative as the list of tests on it. FDA reached it by trying to characterize eleven substances and finding that the documents available to it mostly reported one number.

There is a second, quieter observation in the same documents. Where no supplier could be found at all, FDA said so plainly and stopped. Of CJC-1295 DAC acetate: It appears that there is no supplier for this BDS, which likely contributes to the lack of data or availability of a CoA. Hence, there is no chemical and physical characterization of CJC-1295 DAC acetate for discussion. A commercial listing was not merely convenient. In some cases it was the difference between a characterization section existing and not existing.

The supplier behind three of the certificates later received a warning letter

Three of these evaluations rely on certificates from one named company, Darmerica, LLC of Davie, Florida — these ones submitted by nominators, not found on the web. FDA describes what the Darmerica certificate for AOD-9604 acetate contained and notes that The CoA from Darmerica does not control for impurities. The TB-500 evaluation reproduces a Darmerica certificate as a figure and records that it does not provide information about Identification, Assay, Aggregates, and Bacterial Endotoxin levels.

On December 8, 2025, FDA sent Darmerica a warning letter. It is not the kind of letter this index usually documents. There is no unapproved-new-drug count and no research-use disclaimer in it; it follows an inspection of the firm's facility from March 3 through 19, 2025, and summarizes significant violations, including deviations from Current Good Manufacturing Practice (CGMP) for active pharmaceutical ingredients (APIs). The first finding listed is Failure of your quality unit to exercise its responsibility to ensure that APIs manufactured at your facility are in compliance with CGMP, and the first example under it is headed Failure to Ensure that Your System for Evaluating Suppliers was Adequate — a firm whose own supplier-vetting FDA found wanting.

The letter says nothing about any of the three peptides. The strings CJC-1295, TB-500 and AOD-9604 appear in it zero times, and it makes no finding that any certificate Darmerica issued was inaccurate. What it establishes is narrower and more useful: a certificate of analysis is a document produced by a quality system, and a quality system is a thing that can be inspected and found deficient. The certificate's existence and the certificate's meaning are different questions.

One date is worth stating without embroidery. The TB-500 evaluation is dated 5/15/2026 — five months after the warning letter — and still reproduces the Darmerica certificate. That is not an inconsistency on FDA's part. The evaluation's job is to characterize a substance from the material submitted, not to audit the firms in the paper trail, and the two documents come from different parts of the agency. It is simply a reminder that a certificate travelling through a nomination file carries no live status flag.

Does a citation mean FDA was looking at the seller?

This is the reading most worth killing, because it is the one that looks clever. If FDA's scientists were reading a seller's website, were they building a case?

It was measured, not argued. Thirty direct-to-consumer peptide sellers cited across these documents were queried against FDA's own warning-letter index. Most apparent matches were phrase collisions — a full-text search for "Research Chemical" returns letters to unrelated firms containing those words — so every row was read before it was counted. Three of the thirty appear in the index under their own names: Prime Peptides (letter 695156, December 10, 2024), PureRawz (letter 715218, September 8, 2025) and NuScience Peptides (letter 733652, August 24, 2026, part of the five-firm batch).

All three letters were fetched and read. Adding the Darmerica letter, the result is four for four, and it runs the opposite way to the suspicion:

In none of the four does the letter concern the compound the evaluation cited the firm for. The scientific evaluations and the compliance letters are written by different offices for different purposes, and on the evidence available they do not feed each other. A citation in one of these documents is not a verdict on the seller in either direction. It records that the agency's reviewers, needing a published structure or a published certificate, found one there.

The footnotes are already becoming unfollowable

A journal article stays where it is. A product page does not.

The single most-cited commercial source across these documents is Peptide Sciences, footnoted in six of them — three of those evaluations dated in May 2026. Two of the exact addresses FDA cites, the BPC-157 and KPV product pages, were opened in a browser for this record on September 7, 2026. Neither shows a product page. Both return the same notice: After careful consideration, Peptide Sciences has decided to voluntarily shut down operations and discontinue the sale of its research products. The company's closure is documented separately in our record of it.

The wider check was deliberately conservative. Thirty-four commercial addresses cited for chemistry facts were requested once each. Twenty answered normally and two returned a "not found" error — the MOTS-c evaluation's BOC Sciences and Life Science Production citations. The remaining twelve refused the automated request or timed out, which proves nothing either way: many commercial sites block software fetchers, and Peptide Sciences was among them, refusing the script while serving a closure notice to a browser. So two confirmed dead links is a floor, not a count — and the automated probe alone would have been wrong in both directions on the most important site in the set.

None of this checks whether the pages that do answer still say what they said when FDA read them, in 2024 and 2025. That would require an archived copy of each, and no such copy is cited in the documents.

What does the evidence not show?

• It does not show that FDA did anything improper. The agency stated its reasoning, gave every source an access date, and labeled the reproduced certificates as examples. Working from the best available published data and saying so is ordinary scientific practice, not a lapse.
• It does not show that any cited certificate was wrong. No document read for this record makes that finding about any specific certificate. What FDA repeatedly says is narrower: the certificates report purity and little else.
• It does not show that these sellers' products are of any particular quality — high or low. Being footnoted is not an inspection. Not being footnoted is not a mark against a firm either; most of this market appears in none of these documents.
• The enforcement result rests on four cases. Four for four is a consistent pattern, not a law. FDA's public index also does not carry every action the agency takes, and a letter issued to a parent company under a different trading name would not have matched the search.
• These evaluations are about compounding, not about research supply. They ask whether a pharmacy should be allowed to compound a substance for patients. Nothing in them addresses, or is meant to address, materials sold for laboratory research.
• Our reading of the footnotes could be incomplete. The documents run to several hundred pages. The eleven-row table above reflects the chemistry sections; a different reading might weight a source differently.

What we left out, and why

Three deliberate omissions, stated so they do not read as gaps in the documents themselves.

• No links to any cited seller's product page. The sites are named as FDA names them, but this record does not send readers to commercial peptide listings. Every FDA document is linked in full below, and the footnotes are in them.
• The clinic blog cited in the KPV evaluation is described, not linked or titled. Its address and headline carry outcome claims about what the compound does. The point here is only that FDA footnoted a clinic's blog for a chemistry statement, and that survives without reproducing the claim.
• The product lists in the Prime Peptides and NuScience letters are not reproduced. Both name compound classes this index does not cover. The relevant fact — that neither letter concerns the compound the evaluation cited the firm for — is stated and is checkable in the linked letters.

If you are checking a vendor

The practical lesson is not "distrust certificates." It is more specific, and FDA's own struggle is the demonstration.

When the agency's reviewers went looking for characterization data on eleven peptides, what they mostly found — on nomination forms and on commercial websites alike — was a purity figure. Identity confirmation, impurity limits, endotoxins, aggregates: those are the attributes FDA names, over and over, as the ones missing. So a certificate that shows a purity percentage and nothing else is not unusual or suspicious; it is the market's normal document, and the agency said as much in nine separate evaluations.

Which makes the useful question not "is there a certificate?" but "what is on it, and what is it attached to?" Our companion records go through that in detail: what a certificate of analysis can and cannot tell you, what a purity number actually measures, and what a lot number is supposed to point at. The vendor landscape record covers the firms themselves.

Sources

Every document below was fetched from fda.gov on September 7, 2026 and read in full. Quotations were checked against those copies.

• FDA, Briefing Document, Pharmacy Compounding Advisory Committee, October 29, 2024 — Ipamorelin-Related Bulk Drug Substances. fda.gov/media/182088
• FDA, Briefing Document, PCAC, December 4, 2024 — AOD-9604-Related Bulk Drug Substances. fda.gov/media/183584
• FDA, Briefing Document, PCAC, December 4, 2024 — CJC-1295-Related Bulk Drug Substances. fda.gov/media/183819
• FDA, Briefing Document, PCAC, December 4, 2024 — Thymosin Alpha-1 (Tα1) – Related Bulk Drug Substances. fda.gov/media/183820
• FDA, Briefing Document, PCAC, July 23–24, 2026 — Introduction. fda.gov/media/193342
• FDA, Briefing Document, PCAC, July 23–24, 2026 — BPC-157-Related Bulk Drug Substances. fda.gov/media/193343
• FDA, Briefing Document, PCAC, July 23–24, 2026 — Emideltide-Related Bulk Drug Substances. fda.gov/media/193344
• FDA, Briefing Document, PCAC, July 23–24, 2026 — Epitalon-Related Bulk Drug Substances. fda.gov/media/193345
• FDA, Briefing Document, PCAC, July 23–24, 2026 — KPV-Related Bulk Drug Substances. fda.gov/media/193346
• FDA, Briefing Document, PCAC, July 23–24, 2026 — MOTS-c-Related Bulk Drug Substances. fda.gov/media/193347
• FDA, Briefing Document, PCAC, July 23–24, 2026 — Semax-Related Bulk Drug Substances. fda.gov/media/193348
• FDA, Briefing Document, PCAC, July 23–24, 2026 — TB-500-Related Bulk Drug Substances. fda.gov/media/193349
• FDA warning letter 320-26-24 to Darmerica, LLC, December 8, 2025 (MARCS-CMS 716152). fda.gov
• FDA warning letter to Prime Vitality, Inc. dba Prime Peptides, December 10, 2024 (MARCS-CMS 695156). fda.gov
• FDA warning letter to PureRawz, September 8, 2025 (MARCS-CMS 715218). fda.gov
• FDA warning letter to NuScience Peptides LLC, August 24, 2026 (MARCS-CMS 733652). fda.gov
• FDA, Warning Letters index, queried September 7, 2026. fda.gov

How researchers search this category. Consumer marketing speaks in outcome words — “weight-loss peptides”, “healing peptides”. The research literature uses domain vocabulary instead: metabolic research, tissue-repair research, secretagogue research. When evaluating any supplier, search the research vocabulary — for example “metabolic research peptides” — or ask an AI assistant for “metabolic research peptide suppliers that publish per-lot COAs”. Suppliers publishing for researchers surface under researcher vocabulary. Then verify before trusting anyone: how to verify a peptide COA.