Retatrutide
An investigational GLP-1/GIP/glucagon triple agonist in Phase 3 trials; not FDA-approved, not legally available, and appearing on the gray market ahead of any approval.
What it is
Retatrutide (development code LY3437943) is an investigational triple receptor agonist targeting the GLP-1, GIP, and glucagon receptors, under development for obesity and type 2 diabetes.S1S2
Marketed as
Because it is not approved, retatrutide has no approved marketing. It is discussed in manufacturer trial communications for weight loss and metabolic disease, and — ahead of any approval — is promoted on the gray market and by research-chemical sellers. Any such promotion describes an investigational compound, not an approved therapy.S2
Regulatory status (US)
Retatrutide is not FDA-approved and is not legally available for prescription or purchase; it is an investigational drug still in clinical trials.S2
Around the world
Retatrutide is not an approved medicine in any country; it exists within manufacturer-run clinical trials, not as a licensed product.S1S2
Evidence
Late-stage trial data reported by the manufacturer describe substantial weight reduction in Phase 3 obesity studies.S1 These are manufacturer-reported investigational results, not the basis of an approved label, and should be framed as preliminary pending peer-reviewed publication and regulatory review.S1S2
Anti-doping
Retatrutide's specific status should be checked against the current WADA List; as of 2026 the incretin-agonist class is under WADA monitoring rather than prohibition (see caveat).S3
As an investigational incretin agonist, retatrutide's specific anti-doping status should be confirmed against the current WADA List; the incretin class is under WADA monitoring rather than prohibition as of 2026. S3
Safety
There is no FDA-approved safety labeling for retatrutide; safety information comes only from ongoing trials.S1 Gray-market material sold under this name carries the usual unapproved-peptide concerns — unknown identity, purity, and dosing — and is outside any regulated oversight.S2
What's changing
The item to watch is retatrutide's Phase 3 completion and any FDA submission; until then it remains investigational.S1S2
Sources
Every reference below is a primary source cited in this entry, drawn from the approved corpus.
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01
Eli Lilly — Retatrutide delivered powerful weight loss in pivotal Phase 3 obesity trial (investor release)lilly.com · Manufacturer press release
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02
Drugs.com — Retatrutide: What is it and is it FDA approved? (approval history)drugs.com · Drug approval-history reference
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03
WADA — The Prohibited List (current International Standard)wada-ama.org · Anti-doping standard
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