None of the six peptides FDA’s compounding advisers backed in July 2026 has a completed, peer-reviewed controlled trial of the compound itself in humans. BPC-157, Semax and Epitalon have small or uncontrolled human studies. TB-500, KPV and MOTS-c have no published human dosing data at all, according to FDA’s own briefing documents. The votes were real. The evidence base is thin.
As of October 9, 2026, FDA’s meeting page posts the briefing documents and voting questions but no minutes. The tallies below come from trade press reports, and each compound actually received two votes, one for the free base and one for the acetate salt. What happens procedurally after the vote is covered in what happens next after the advisory vote.
FDA staff recommended against all six, on the same core grounds
Each briefing document reached the same conclusion: neither form should be added to the 503A bulks list. The recurring reasons were that the substance is not well characterized (no standard name, no public specifications for impurities, aggregates or endotoxin), that peptides given by injection or nasal spray may carry an immunogenicity risk, and that FDA-approved therapies exist for the nominated uses. The committee voted the other way. One voting pharmacist said his yes vote was meant to “put this decision back into the hands of the patient, the physician and the pharmacist,” Pharmaceutical Executive reported.
| Peptide | Origin | Best human evidence | Key citation | FDA staff concern | Reported vote |
|---|---|---|---|---|---|
| BPC-157 | Synthetic 15-amino-acid fragment of a gastric protein | Small, uncontrolled pilots; one controlled trial known only from a 2005 meeting abstract | PMID 39325560 | Immunogenicity; no human PK; nonclinical toxicology too limited | 8-6, 1 abstention |
| TB-500 | Synthetic Ac-LKKTETQ, residues 17 to 23 of thymosin beta-4 | None for TB-500 itself | PMID 22962027 (identity) | No human data by any route; no nonclinical toxicity studies | 8-6, 1 abstention |
| KPV | Tripeptide from the tail of alpha-MSH | None | PMID 18061177 (mice) | No human data; immunogenicity not assessed | 8-6, 1 abstention |
| MOTS-c | 16-amino-acid mitochondrial-encoded peptide | None for administered MOTS-c | PMID 25738459 (mice) | No human data; molecular target unknown | 7-5, 2 abstentions |
| Semax | Synthetic ACTH(4-10) analog, registered in Russia | Russian-language clinical studies; FDA reviewed only two English references | PMID 29798983 | Possible bleeding risk; dopamine signal in mice | 8-5 (one outlet adds 1 abstention) |
| Epitalon | Synthetic tetrapeptide (Ala-Glu-Asp-Gly) | One small placebo-controlled study of melatonin markers, no sleep outcomes | PMID 33280326 | Telomerase activation and theoretical cancer risk; no human safety data | 7-4 or 7-5, 1 abstention (reports differ) |
Vote sources: Pharmaceutical Executive and the American Med Spa Association for July 23; RAPS and AmSpa for July 24.
BPC-157 has the most human data, and none of it is conclusive
FDA located five clinical reports. The only controlled one, a 53-patient ulcerative colitis trial of a BPC-157 enema, exists as a 2005 meeting abstract; FDA calculated that the difference from placebo was not significant and called the data inadequate. A retrospective chart review of 16 reachable patients reported knee pain relief after intra-articular injection, with some patients also receiving thymosin beta-4 (PMID 34324435). A 12-patient uncontrolled pilot reported symptom resolution in 10 women with interstitial cystitis (PMID 39325560). A two-person IV infusion study reported no side effects (PMID 40131143).
FDA’s concern: no human pharmacokinetic data, no study by the proposed oral, subcutaneous, nasal or transdermal routes, and FAERS reports of injection site reactions, shortness of breath and skin darkening whose relationship to BPC-157 FDA called unclear.
Supporters’ strongest point: every human report published so far describes the peptide as well tolerated, and the interstitial cystitis pilot used product from a 503A pharmacy (PMID 39325560). Status: BPC-157.
TB-500 is a fragment, and the human trials used the full protein
TB-500 is the acetylated heptapeptide Ac-LKKTETQ, identified by a doping-control lab in the product sold under that name (PMID 22962027). FDA states that TB-500 and thymosin beta-4 “are not the same substance” and found no article in which TB-500 was given to humans. FDA also cited an in vitro study in which TB-500 did not close scratch wounds in fibroblasts.
Supporters’ strongest point: full-length thymosin beta-4 (43 amino acids) has reached phase 2. A topical gel trial in 73 patients with venous ulcers reported acceptable safety (PMID 20536470), and an eye-drop trial in 72 patients missed its primary endpoints but reported secondary improvements (PMID 26056426). Those studies used the full protein, so they do not answer questions about the fragment. Status: TB-500.
KPV and MOTS-c have no human dosing data
For KPV, nominated for wound healing and inflammatory conditions, FDA “did not find any information on the use of these substances administered in humans.” The supporting science is cell and mouse work: oral KPV reduced inflammation in two mouse colitis models (PMID 18061177).
For MOTS-c, nominated for obesity and osteoporosis, FDA found no human data by any route and noted that its molecular targets remain unknown. Supporters point to the discovery paper, where MOTS-c prevented diet-induced obesity and insulin resistance in mice (PMID 25738459), and to a study reporting that exercise raises the body’s own MOTS-c levels in humans (PMID 33473109). Endogenous levels are a different question from injected product. Status: MOTS-c.
Semax and Epitalon rest mostly on Russian research
Semax is registered in Russia as nasal drops. FDA set aside Russian-language references without certified translations and reviewed two English sources for migraine and trigeminal neuralgia, which it said showed lack of effectiveness in small samples. A Russian study of 110 stroke patients reported higher plasma BDNF and better Barthel index recovery in the semax subgroups (PMID 29798983); the abstract does not describe randomization. FDA flagged a possible antithrombotic effect, with bleeding risk, and a mouse finding that semax potentiated amphetamine-induced dopamine release. Status: Semax.
For Epitalon, nominated for insomnia, the best human study described a placebo-controlled trial in 40 middle-aged women on night shifts with low melatonin markers; a sublingual spray raised a urinary melatonin metabolite 1.7-fold (PMID 33280326). FDA noted it measured no sleep outcomes, did not specify blinding, and used a different route from the proposed injection. FDA also wrote that epitalon “has the potential to be carcinogenic” mechanistically, because it activates telomerase, and that mouse tumor studies were too limited to settle the question. Status: Epitalon.
A committee vote measures opinion, not efficacy
An advisory vote tells you how a panel weighed incomplete evidence. It adds no data. Every trial cited above existed before July 23, and FDA’s reviewers read the same record and reached the opposite conclusion. Listing on 21 CFR 216.23 requires notice-and-comment rulemaking, and even a listing would make a substance eligible for 503A compounding. It would not establish that the substance works or is safe for any use.
What this means for you
Keep all six off your menu until a lawful pathway exists, and treat any listing as the start of your diligence. If FDA lists one, require four things before offering it: the published rule in hand; product sourced only from a licensed 503A pharmacy filling patient-specific prescriptions, with a certificate of analysis that covers identity, impurities and endotoxin (see 503A vs 503B sourcing); a written informed consent that states the evidence level from this page; and adverse-event tracking under a protocol your medical director has signed (adverse event response). If you want that framework built before a rule arrives, book a call.
Frequently asked questions
Is there a human clinical trial of BPC-157?
FDA identified one randomized, placebo-controlled trial, a 2005 ulcerative colitis study of an enema, published only as a meeting abstract. FDA found the data inadequate. The other human reports are a retrospective chart review, an uncontrolled 12-patient pilot and a two-person infusion study, all small and short.
Is TB-500 the same as thymosin beta-4?
No. TB-500 is the seven-amino-acid acetylated fragment Ac-LKKTETQ. Thymosin beta-4 is the 43-amino-acid protein. FDA’s July 2026 briefing states they are different substances, and the phase 2 human trials used the full protein, so their results do not transfer to the fragment.
Did the FDA approve these peptides in July 2026?
No. An advisory committee voted, in nonbinding votes, to recommend adding six peptides to the 503A bulks list. FDA staff had recommended against all six. As of October 9, 2026, no proposed rule has appeared, and a listing would permit compounding without approving anything.
Has MOTS-c been tested in humans?
FDA’s briefing found no human data for administered MOTS-c by any route. Published research is in cells and mice. One study reported that exercise raises the body’s own MOTS-c levels in people, which is a separate question from injecting a compounded product.
This is general information, not legal advice. Rules vary by state and change. Confirm your own facts with counsel.