PeptidesInfo

Research area

Regulation and approval

Regulatory status is a fact about a decision, not an opinion about evidence, and it changes. This hub tracks the U.S. status of profiled peptides, explains the compounding categories that shape what clinics can legally offer, and links to the primary FDA sources.

Abstract illustration of a peptide chain used as the regulation and approval research hub image

Evidence map: peptides studied in this area

How grades work →
PeptideEvidence for this areaRegulatory statusWhat has been studied
SemaglutideEstablished evidenceFDA-approved for this useFDA-approved (Ozempic 2017, Rybelsus 2019, Wegovy 2021; CV indication 2024). Was on the FDA drug-shortage list, enabling compounding, until the shortage was declared resolved in February 2025.
TirzepatideEstablished evidenceFDA-approved for this useFDA-approved (Mounjaro 2022, Zepbound 2023). Shortage declared resolved in late 2024, ending the compounding window.
TesamorelinEstablished evidenceFDA-approved for this useFDA-approved (Egrifta 2010) for HIV-associated lipodystrophy abdominal fat.
PT-141Established evidenceFDA-approved for this useFDA-approved as bremelanotide (Vyleesi, June 2019) for HSDD in premenopausal women.
Collagen peptidesEstablished evidenceNot FDA-approvedRegulated as a food/dietary supplement ingredient (GRAS), not a drug; no approval process applies.
BPC-157Unsupported evidenceNot FDA-approvedNot FDA-approved. Placed in category 2 of the compounding interim policies (Sept 2023); nomination later withdrawn, which does not make it compoundable.
TB-500Unsupported evidenceNot FDA-approvedNot FDA-approved. Thymosin beta-4 has been in registered clinical trials; the TB-500 fragment has not.
CJC-1295Unsupported evidenceNot FDA-approvedNot FDA-approved; development discontinued. Category 2 nomination withdrawn; still not on the 503A bulks list.
IpamorelinUnsupported evidenceNot FDA-approvedNot FDA-approved; development discontinued. Ipamorelin acetate remains in category 2 under the 503B policy.
GHK-CuUnsupported evidenceNot FDA-approvedNot FDA-approved as a drug; used as a cosmetic ingredient. Injectable GHK-Cu products are unapproved drugs.

Grades reflect the strength of evidence for this research area specifically. Definitions: Established, Promising, Preliminary, Preclinical, Unsupported, Conflicting.

Why we track regulation separately

Approval tells you a regulator reviewed a specific product for a specific use and judged the benefit–risk acceptable. It does not tell you the drug works for every use people put it to, and non-approval does not tell you a compound is ineffective — it may simply never have been submitted. That is why every page on this site shows regulatory status and an evidence level. On this hub, the "evidence" column grades how well the regulatory position itself is documented from primary sources.

The categories that matter in the U.S.

  • FDA-approved drug: reviewed under an NDA/BLA; has a label with indications, warnings and dosing. Semaglutide, tirzepatide, tesamorelin and bremelanotide are in this group.
  • Off-label use of an approved drug: legal for a prescriber, but the evidence for the off-label use may be thin. Tesamorelin for body composition outside HIV lipodystrophy is the clearest peptide example.
  • Investigational: being studied under an IND in registered trials; not available for marketing.
  • Compounding under 503A/503B: a pharmacy may compound from a bulk substance only if it has a USP/NF monograph, is a component of an approved drug, or is on the 503A bulks list. While nominations are evaluated, FDA sorts them into interim categories; category 2 holds substances it judges to present significant safety risks. Several popular peptides were placed there in September 2023; by the list current at 22 April 2026 most of those nominations had been withdrawn by the nominators, while ipamorelin acetate (503B) and kisspeptin-10 (503A) remain. None of it makes these peptides compoundable. Compounding of semaglutide and tirzepatide was separately permitted while those drugs were on the shortage list; both shortages have since been declared resolved.
  • "Research use only" (RUO): a labelling convention, not an FDA category. Products sold this way for human use are unapproved drugs, and their manufacturing is not held to pharmaceutical standards.

What changed recently, and what we watch

  • Shortage resolutions for tirzepatide (2024) and semaglutide (2025) closed the legal window for most compounded versions; the FDA has since acted against sellers of compounded and counterfeit GLP-1 products.
  • The FDA's compounding-category lists change: the category 2 page was current as of 22 April 2026 at our last check, and the Pharmacy Compounding Advisory Committee met on 23–24 July 2026 to consider several peptides for 503A eligibility. We have not yet been able to verify the outcome of that meeting from a primary FDA document, so we do not state one. We re-check quarterly.
  • State-level actions against peptide clinics and telehealth sellers are increasing.

Regulatory positions are dated on every profile. If a status here is more than a quarter old, verify it against the FDA source before relying on it.

Analyses in regulation and approval

Foundations4 min read

FDA-Approved vs Proven Effective: Why They Are Not the Same

"FDA-approved" and "works" are different questions, and conflating them is how most peptide confusion starts. This explains the two independent axes — regulatory status and evidence level — with four worked examples.

Safety4 min read

Counterfeit and Fake GLP-1 Products: How to Spot Them

Fake and counterfeit versions of semaglutide and tirzepatide are being sold online, sometimes with made-up pharmacy labels. Here is how the FDA says to recognize them and buy safely.

Regulation4 min read

Compounded Semaglutide: What the FDA Actually Says

Compounded semaglutide is not the same as Ozempic or Wegovy. It is not FDA-checked, the shortage that made it common is over, and the FDA has linked it to dosing errors and hospital visits. Here is the plain version.

Benefits5 min read

GLP-1 Benefits Beyond Weight Loss: Heart, Kidney, Liver, and Sleep

Semaglutide and tirzepatide have now shown benefits in cardiovascular events, kidney disease, liver disease, heart failure and sleep apnoea — each in its own trial, in its own population. Here is what each one actually demonstrated.

Research analysis5 min read

GLP-1 Peptides: Established Uses Versus Emerging Research

Semaglutide and tirzepatide are the best-evidenced peptides in medicine — for specific uses. We separate the approved indications with large trials from the emerging research (kidney, liver, heart failure, sleep apnoea, Alzheimer's) and the open questions about regain, muscle loss and compounded products.

Research analysis6 min read

BPC-157: Human Evidence, Animal Research, and Open Questions

BPC-157 has hundreds of positive animal studies and almost no controlled human data. We separate what the rat research shows, what the few human reports show, what the FDA has said, and what would have to happen for the evidence grade to change.

Safety5 min read

Peptide Purity, Contamination, and the Limits of a Certificate of Analysis

A certificate of analysis is the main reassurance offered by 'research peptide' vendors. Here is what a CoA can and cannot tell you — identity, purity, quantity, sterility, endotoxin — why '99% pure' is not what it sounds like, and what independent testing of grey-market peptides has found.

Research analysis5 min read

CJC-1295 and Ipamorelin: Growth Hormone Research and Unanswered Risks

The 'CJC/ipa' stack is sold for muscle, fat loss, sleep and anti-aging. The human evidence is a handful of short hormone-level studies, two abandoned development programmes, and no outcome trials — plus a set of risks that have never been studied because the trials were never run.

Research analysis4 min read

Tesamorelin: Approved Use, Off-Label Interest, and Clinical Evidence

Tesamorelin is the one GHRH analogue that finished phase 3 and won FDA approval — for excess abdominal fat in HIV-associated lipodystrophy. We separate that established evidence from the off-label uses it is now marketed for: general visceral fat, liver fat, and cognition.

Research analysis4 min read

TB-500 and Thymosin Beta-4: What the Research Actually Studies

TB-500 is sold on the back of thymosin beta-4 research — a different molecule with real but early human trials in wounds and eye disease. We untangle which studies are about what, and what that means for the fragment people actually buy.

Research analysis4 min read

PT-141: Mechanism, Approved Use, Benefits, and Limitations

PT-141 (bremelanotide) is FDA-approved as Vyleesi for low sexual desire in premenopausal women, with modest benefits and a lot of nausea. Its use in men — the way it is mostly marketed online — was abandoned in development. Here is what the trials actually showed.

Regulation6 min read

FDA-Approved, Off-Label, Investigational, and Unapproved Peptides

The regulatory status of a peptide is a fact about a decision, not a verdict on the evidence. This guide explains the four categories, what compounding rules changed in 2023–2025, and where every peptide we cover currently sits.

Foundations4 min read

What Are Peptides? A Research-Based Introduction

Peptides are short chains of amino acids that range from approved blockbuster drugs to unregulated 'research chemicals'. Here is what the word actually covers, how peptides differ from proteins and small-molecule drugs, and why the category tells you nothing about evidence.