Cardarine (GW-501516)
Aliases: GW501516 · Endurobol · Cardarine
Last verified: 2026-09-23
The short version
Cardarine is the most instructive case on the entire list: it looked like a metabolic 'exercise in a pill' in early phases, and then animal studies showed rapid tumor development (including highly malignant ones) at doses relatively close to those used. Development was terminated. On the gray market it is sold as an 'endurance booster' regardless — this is buying a proven risk.
Identity & type
- Molecular type
- small-molecule
- Sequence / structure
- — (PPARδ agonist)
- Molecular weight
- ~453 Da
- Formula
- C21H18F3NO3S2
- Origin
- PPARδ agonist (GW-501516) developed for metabolism; development halted due to cancers in animals.
Mechanism of action
PPARδ activation → increased β-oxidation and fiber shift to oxidative type.
not confirmed in humans
Dosing & routes
Official / clinical context
Development was abandoned; no active regulatory document exists. There are no official indications.
Regulator-approved labeling and published study designs — never a recommendation.
Community-reported practice
Community: 10–20 mg/day (long-term use NOT recommended). Pronounced endurance (running/cardio "easier" by 20–30% subjectively) and leaning out; but the community is increasingly cautious due to rodent carcinogenicity — long-term use is recommended less and less.
Unverified self-reports. Not medical advice. Not endorsement.
Expected effects (community)
Pronounced endurance (running/cardio "easier" by 20–30% subjectively) and leaning out; but the community is increasingly cautious due to rodent carcinogenicity — long-term use is recommended less and less.
Protocol — official vs community
Official / label
No approved product. Development abandoned after carcinogenicity in rodent studies at high doses.
Duration: —
PPAR-delta agonist, not a SARM — the rodent cancer signal is the permanent asterisk.
Community (anecdotal)
10–20 mg oral daily, usually pre-cardio or with training meals.
- Cycle:
- 8–12 weeks.
- Break:
- 4+ weeks.
The cancer question is dose/species-dependent and unresolved for humans — the community treats 'unresolved' as 'fine', which is a choice.
Human evidence
Early phase I/II (lipids, insulin sensitivity) — program terminated before mature results.
Preclinical evidence
GSK Phase I/II (lipids, metabolism) — halted 2007 over tox findings.
Known risks
- Tumors at multiple sites in animals — reason development was haltedcharacterized
- WADA prohibition (metabolic modulators, S4)characterized
Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.
Unknowns & evidence gaps
- — (development abandoned due to safety signal)
Frequently asked questions
References
- Newsholme P. / GSK — termination of the GW501516 program