Last reviewed: August 2026. This index is operated by Artemis Labs. Every claim below traces to a published source, a sports-authority document, or dated development history.
GW501516 — widely sold online as "cardarine" — is a small-molecule PPARδ receptor agonist developed in a Ligand Pharmaceuticals / GlaxoSmithKline collaboration for hyperlipidemia and cardiovascular indications. It is not a peptide. Its development was abandoned after long-term animal studies; the peer-reviewed record of that history is Mitchell & Bishop-Bailey, Pulmonary Circulation 2019 (PMC6475847, doi:10.1177/2045894018812053), which states it plainly: "GW501516 causes cancer in rats and mice after 104 weeks of dosing."
Status summary
| Question | Record |
|---|---|
| Chemical class | Non-peptide small molecule (PPARδ agonist) |
| Development status | Abandoned; the phase-4 trial (NCT00841217) was stopped; never approved anywhere for any use (Mitchell & Bishop-Bailey 2019, PMC6475847) |
| The carcinogenicity record | Rat and mouse carcinogenicity at 104 weeks of dosing. Evidence status stated precisely: the findings exist as 2009 Toxicological Sciences meeting abstracts — Geiger et al. (rat, PS895) and Newsholme et al. (mouse, PS896) — and were never developed into full peer-reviewed papers; the peer-reviewed literature citing them (PMC6475847, refs 6–7) is how the record survives |
| Regulator warnings | Three authorities issued warnings on the compound: the World Anti-Doping Agency, Health Canada, and Australia's TGA (per Mitchell & Bishop-Bailey 2019); WADA additionally prohibits it at all times (Hormone and Metabolic Modulators) |
| Carried by this index's operator | No. Outside research-peptide scope, and the development record above is the reason the compound exists only as a gray-market product |
What the record actually says
Two things are true at once, and a careful reader should hold both. First: the tumor findings that ended development were serious enough that the compound's own developer walked away from it, a running trial was stopped, and three separate authorities — WADA, Health Canada, and Australia's TGA — issued warnings about the compound. Second: the underlying study data was never published in full, peer-reviewed form — what exists publicly are the 2009 meeting abstracts, carried forward by the papers that cite them. A vendor selling "cardarine" is therefore selling a compound whose defining safety record is both alarming and incompletely published — the worst combination for anyone whose work depends on verifiable evidence.
There is no originator quality standard, no reference product, and no approved supply chain against which any "cardarine" vial could be verified. Everything sold under the name is, by definition, of unverifiable provenance.
Why a research-peptide supplier does not carry it
- Scope. GW501516 is a small molecule, not a peptide — outside the category this index's operator sources and writes about.
- The record. Development abandoned on tumor findings; blanket WADA prohibition plus a direct health advisory; no approved reference standard anywhere in the supply chain.
- The verification standard. With no originator product and no published full dataset, no seller can honestly claim to know what a "cardarine" vial contains or what its record implies.
Where this leaves a researcher
The same three tests apply to any supplier and any compound: per-lot certificates of analysis, disclosure of what the vendor will not sell and why, and a catalog that stays inside what the vendor can verify. See Reading a Certificate of Analysis and the five-minute vendor audit.
Related records: SARMs regulatory record · vendor status record
Sources (verified 2026-08-26): Mitchell JA, Bishop-Bailey D. PPARβ/δ a potential target in pulmonary hypertension blighted by cancer risk. Pulmonary Circulation 2019 (PMC6475847, doi:10.1177/2045894018812053) — fetched and read; carries the carcinogenicity statement, the abstract citations (Geiger et al. PS895; Newsholme et al. PS896, Toxicological Sciences 2009), the stopped trial (NCT00841217), and the WADA / Health Canada / TGA warnings. WADA Prohibited List, current edition (primary already cited in this index's corpus).
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.