US status

Research-only

By Peptide America · Publisher · Reviewed September 2026

Four paths lead here, and they are worth telling apart because they are routinely collapsed into one another. One peptide left Category 2 in April 2026, reached the advisory committee in July, and was refused. Several saw their nominations withdrawn by the nominators, which removes a substance from every category without any finding about it either way. One was never nominated at all, because it is an investigational drug still in development. And one, kisspeptin-10, is still named by FDA in 503A Category 2 itself, which is not an absence of permission but an explicit prohibition; three more, ipamorelin, GHRP-2 and GHRP-6, carry the same Category 2 listing under FDA's separate 503B policy for outsourcing facilities. In every case the arithmetic for a reader is the same: no listing, no approval, no lawful compounding route.

Removal from a prohibition list reads like progress, and sellers of research-use-only material market it that way. It is not an authorization. Material sold under these names is chemical supply produced outside pharmacy licensure, prescriber oversight, and pharmaceutical quality standards; its identity and sterility rest on the vendor's word.

Molecules holding this status

Molecule	Class	US status	Position
CJC-1295	GH secretagogues	Nomination withdrawn	Removed from Category 2 in September 2024 after its nominators withdrew; on no list; no lawful compounding route. Verified August 2026.
Ipamorelin	GH secretagogues	Nomination withdrawn	503A nominations withdrawn September 2024 and in no 503A category; named in Category 2 under FDA's separate 503B policy; no lawful compounding route.
DSIPDelta sleep-inducing peptide; emideltide	Neuropeptides	No lawful route	Removed from Category 2 in April 2026; the only peptide PCAC declined to recommend at the July 2026 meeting; no lawful route. Verified August 2026.
Melanotan IIMelanotan-2; MT-II	Melanocortins	No lawful route	Nomination withdrawn in 2026; on no list. FDA's published safety finding — melanoma, priapism, and two acute toxicity syndromes in case reports — was never retracted. Verified August 2026.
LL-37Cathelicidin LL-37; hCAP18	Immune peptides	No lawful route	Nomination withdrawn in 2026; on no list. FDA's safety finding cites nonclinical evidence of harm to male reproduction and of pro-tumorigenic effects in some tissues. Verified August 2026.
DihexaDihexa acetate; PNB-0408	Neuropeptides	No lawful route	Nomination withdrawn in 2026; on no list. FDA states it has identified no human exposure data for this substance by any route. Verified August 2026.
CerebrolysinPeptide fraction derived from porcine brain protein; FPF-1070	Neuropeptides	No lawful route	Licensed in Austria, never approved in the US; FDA stated in 2020 and 2021 warning letters that it had not been nominated for the 503A bulks list, and no list names it.
PEG-MGFMechano growth factor pegylated; IGF-1Ec	Growth factor fragments	No lawful route	Nomination withdrawn in 2026; on no list. The unpegylated parent, mechano growth factor, sits in Category 3 — nominated without adequate support. Verified August 2026.
AOD-9604hGH fragment 176-191	Growth factor fragments	Nomination withdrawn	The advisory committee voted 0–12 against listing it in December 2024; the nomination was later withdrawn. On no list, and no lawful compounding route. Verified August 2026.
Thymosin alpha-1Thymalfasin; Ta1	Immune peptides	Nomination withdrawn	Licensed as a medicine in other countries and never approved here; the advisory committee voted 4–17 against listing it in December 2024, and the nomination was withdrawn. Verified August 2026.
Kisspeptin-10KP-10; metastin(45–54)	Neuropeptides	No lawful route	The only peptide FDA still lists in Category 2 of the 503A bulks list; placed there September 2023, and the advisory committee voted 0–11 against listing it in October 2024. Verified August 2026.
SelankSelank acetate; TP-7	Neuropeptides	Nomination withdrawn	Nomination withdrawn; on no list, and never placed on an advisory-committee agenda — the disposition with the least record behind it. Verified August 2026.
RetatrutideLY3437943	GLP-1 receptor agonists	No lawful route	Investigational and unapproved; FDA states plainly that it cannot be used in compounding under federal law, and has issued warning letters over research-use-only sales. Verified August 2026.
GHRP-2Growth hormone releasing peptide-2; pralmorelin	GH secretagogues	No lawful route	Category 3 of the 503A bulks list — nominated without adequate support — and Category 2 under the separate 503B policy for injectable and nasal routes; no lawful route.
GHRP-6Growth hormone releasing peptide-6; growth hormone releasing hexapeptide	GH secretagogues	No lawful route	Category 3 of the 503A bulks list — nominated without adequate support — and Category 2 under the separate 503B policy; no lawful route.
Mechano growth factorMGF; IGF-1Ec	Growth factor fragments	No lawful route	Category 3 of the 503A bulks list — nominated without adequate support. The pegylated form sits in no category at all, its nomination withdrawn.
ARA-290Cibinetide; helix B surface peptide	Repair peptides	No lawful route	Category 3 of the 503A bulks list — nominated without adequate support — despite five indexed human trials, which is the distance between a literature and a nomination.
ThymulinThymulin acetate; serum thymic factor	Immune peptides	No lawful route	Category 3 of the 503A bulks list — nominated without adequate support; no approved product and no lawful compounding route.
L-carnosineCarnosine; beta-alanyl-L-histidine	Longevity peptides	No lawful route	Category 3 of the 503A bulks list — nominated without adequate support — despite a large randomized literature, almost all of it oral supplementation.

CJC-1295Nomination withdrawn
Removed from Category 2 in September 2024 after its nominators withdrew; on no list; no lawful compounding route. Verified August 2026.
IpamorelinNomination withdrawn
503A nominations withdrawn September 2024 and in no 503A category; named in Category 2 under FDA's separate 503B policy; no lawful compounding route.
DSIPNo lawful route
Delta sleep-inducing peptide; emideltide
Removed from Category 2 in April 2026; the only peptide PCAC declined to recommend at the July 2026 meeting; no lawful route. Verified August 2026.
Melanotan IINo lawful route
Melanotan-2; MT-II
Nomination withdrawn in 2026; on no list. FDA's published safety finding — melanoma, priapism, and two acute toxicity syndromes in case reports — was never retracted. Verified August 2026.
LL-37No lawful route
Cathelicidin LL-37; hCAP18
Nomination withdrawn in 2026; on no list. FDA's safety finding cites nonclinical evidence of harm to male reproduction and of pro-tumorigenic effects in some tissues. Verified August 2026.
DihexaNo lawful route
Dihexa acetate; PNB-0408
Nomination withdrawn in 2026; on no list. FDA states it has identified no human exposure data for this substance by any route. Verified August 2026.
CerebrolysinNo lawful route
Peptide fraction derived from porcine brain protein; FPF-1070
Licensed in Austria, never approved in the US; FDA stated in 2020 and 2021 warning letters that it had not been nominated for the 503A bulks list, and no list names it.
PEG-MGFNo lawful route
Mechano growth factor pegylated; IGF-1Ec
Nomination withdrawn in 2026; on no list. The unpegylated parent, mechano growth factor, sits in Category 3 — nominated without adequate support. Verified August 2026.
AOD-9604Nomination withdrawn
hGH fragment 176-191
The advisory committee voted 0–12 against listing it in December 2024; the nomination was later withdrawn. On no list, and no lawful compounding route. Verified August 2026.
Thymosin alpha-1Nomination withdrawn
Thymalfasin; Ta1
Licensed as a medicine in other countries and never approved here; the advisory committee voted 4–17 against listing it in December 2024, and the nomination was withdrawn. Verified August 2026.
Kisspeptin-10No lawful route
KP-10; metastin(45–54)
The only peptide FDA still lists in Category 2 of the 503A bulks list; placed there September 2023, and the advisory committee voted 0–11 against listing it in October 2024. Verified August 2026.
SelankNomination withdrawn
Selank acetate; TP-7
Nomination withdrawn; on no list, and never placed on an advisory-committee agenda — the disposition with the least record behind it. Verified August 2026.
RetatrutideNo lawful route
LY3437943
Investigational and unapproved; FDA states plainly that it cannot be used in compounding under federal law, and has issued warning letters over research-use-only sales. Verified August 2026.
GHRP-2No lawful route
Growth hormone releasing peptide-2; pralmorelin
Category 3 of the 503A bulks list — nominated without adequate support — and Category 2 under the separate 503B policy for injectable and nasal routes; no lawful route.
GHRP-6No lawful route
Growth hormone releasing peptide-6; growth hormone releasing hexapeptide
Category 3 of the 503A bulks list — nominated without adequate support — and Category 2 under the separate 503B policy; no lawful route.
Mechano growth factorNo lawful route
MGF; IGF-1Ec
Category 3 of the 503A bulks list — nominated without adequate support. The pegylated form sits in no category at all, its nomination withdrawn.
ARA-290No lawful route
Cibinetide; helix B surface peptide
Category 3 of the 503A bulks list — nominated without adequate support — despite five indexed human trials, which is the distance between a literature and a nomination.
ThymulinNo lawful route
Thymulin acetate; serum thymic factor
Category 3 of the 503A bulks list — nominated without adequate support; no approved product and no lawful compounding route.
L-carnosineNo lawful route
Carnosine; beta-alanyl-L-histidine
Category 3 of the 503A bulks list — nominated without adequate support — despite a large randomized literature, almost all of it oral supplementation.

When the FDA schedules further advisory review, molecules move from this page to pending; the molecule index always carries the current filing.

Elsewhere in this index

Evidence reviews

CJC-1295 With Ipamorelin: The EvidenceWhat is known about CJC-1295 taken with ipamorelin?
CJC-1295: A Withdrawal, Not a ClearanceWhy did CJC-1295 leave Category 2 in September 2024, and what is its status now?
Sermorelin vs Tesamorelin: How They DifferHow do sermorelin and tesamorelin differ?
Ipamorelin's One Trial Missed Its EndpointWhat did the one randomized controlled trial of ipamorelin find?
DSIP: The Committee's Only RejectionWhy was DSIP the only peptide the July 2026 committee refused to recommend?
Melanotan I vs II: One Approved, One NotWhat is the difference between Melanotan I and Melanotan II?
Melanotan II: The Record on a Tanning PeptideWhat is the record on Melanotan II, which was removed from Category 2 and never reviewed?
LL-37 Wound Healing: What Trials FoundDo LL-37 wound studies establish that the peptide works?
Cerebrolysin After Stroke: Mixed EvidenceWhy do Cerebrolysin stroke trials appear to disagree?
Peptides for Weight Loss, by US Legal StatusWhich peptides sold for weight loss are actually FDA-approved for it?
Thymosin Alpha-1: Sepsis Trial ResultsDoes thymosin alpha-1 improve survival in sepsis?
Kisspeptin-10 and Testosterone: EvidenceDoes kisspeptin-10 treat low testosterone?
Semax vs Selank: Two Russian Peptides ComparedHow do Semax and Selank differ, and what is the evidence and legal status of each?
Retatrutide and Lean Mass: Trial EvidenceDoes retatrutide preserve muscle while reducing body fat?
Incretin Pipeline: Retatrutide and CagriSemaWhich incretin drugs are approved, which are still in trials, and which of them are peptides?
Category 3: Nominated, Not ReviewedWhat does Category 3 of the FDA 503A bulks list actually mean?
What the GHRP Trial Records MeasureDo the trial records for GHRP-2 and GHRP-6 support the uses the compounds are sold for?
ARA-290 for Neuropathy: Trial FindingsDoes ARA-290 have convincing evidence for neuropathic pain?
Thymulin's Eight Trials Measure ZincDo thymulin's eight trial-type records show that the peptide has been tested in people?
Carnosine: Glucose and Vascular EvidenceWhy do carnosine studies report positive and negative metabolic results?

Reference tables

The 2026 recordWhat happened to United States peptide compounding law in 2026, in order?
The nomination trackerWhat became of each peptide's nomination to the 503A bulks list?
The human trial record, by moleculeHow many human clinical trials exist for each peptide in this index?
The WADA Prohibited ListWhich peptides in this index are prohibited in sport, and under which class?
The July 2026 vote ledgerHow did the advisory committee vote on each peptide, and what does a vote do?
Removal is not permissionThe peptides removed from Category 2 in April 2026 — are they lawful now?
Final-action watchHas the FDA finalized anything on the peptides recommended in July 2026?

Definitions

Category 2Substances with identified safety concerns; placement bars pharmacy compounding, and removal from it authorizes nothing.
Research-use-onlyA labeling posture that places material outside drug regulation. It is not a safety statement and it does not make sale for human use lawful.
Category 3Substances whose nomination to the 503A bulks list did not contain enough for the FDA to evaluate.
The Prohibited ListThe World Anti-Doping Agency's annual list of substances and methods prohibited in sport.
Dietary supplementA separate regulatory regime with no pre-market approval requirement and a much lower evidentiary threshold.
All glossary terms