U.S. regulatory status

Retatrutide

Also known as LY3437943 · GIP/GLP-1/glucagon triple agonist · triple G

RestrictedInvestigational only - no approved form exists anywhere; cannot be compounded; FDA warning letters target sellers

Is Retatrutide legal right now?

Retatrutide is an investigational drug - Eli Lilly's GIP/GLP-1/glucagon triple agonist - with no approved form anywhere in the world. Five Phase 3 TRIUMPH trials have read out positively and Lilly has said it plans to submit a Biologics License Application to the FDA in the first quarter of 2027, but until approval there is no legal commercial product. Compounding is not an option either: retatrutide is not a component of any approved drug, has never been on the FDA shortage list, and is not an eligible bulk substance - so the pathways that briefly permitted compounded semaglutide and tirzepatide never applied to it. The FDA states plainly that retatrutide cannot be used in compounding, and it has sent warning letters to sellers offering it as a 'research' chemical - including under coded names - treating that framing as immaterial when the product is aimed at human use. Note this entry sits outside the 503A pipeline entirely: no advisory-committee review of retatrutide is scheduled or on record.

Restricted: Prescription-only, banned, controlled, or under active FDA enforcement.

Verified Aug 22, 2026 (ET) · status held since Sep 9, 2025

Primary source: FDA All 8 sources Reconstitution calculator Compared: vs Semaglutide

Where it sits in the process

Nominated (stalled here - not advancing)
Under review (not reached)
Rulemaking (not reached)
Compounding-legal (not reached)

Not on a path to the 503A list right now. The process stalled or reversed at this stage - read the status above. Sitting at an earlier step is not a sign it will advance.

Next scheduled dateLilly BLA submission to the FDA expected in Q1 2027 - an approval decision would follow well after - Mar 31, 2027 (in 216 days)

What changed last

No recorded changes yet - this entry has held one status since it was added.

Status elsewhere

Retatrutide: regulatory status by jurisdiction
Jurisdiction	Status	Note
United States (FDA)	Restricted	Investigational; not approved, not compoundable (never on the shortage list, not an eligible bulk substance). FDA warning letters to sellers, including products sold under coded names.
Sport / anti-doping (WADA)	Restricted	Prohibited at all times, but not listed by name - captured by the S0 catch-all for substances with no regulatory approval for human use.

Sources & transparency

Sources for this entry

FDA - FDA's concerns with unapproved GLP-1 drugs used for weight loss FDA · primaryStates that retatrutide (and cagrilintide) are not components of FDA-approved drugs and cannot be used in compounding.
FDA - warning letter, GLP-1 Solution (Sep 9, 2025) FDA · primaryRepresentative enforcement letter in the FDA's clampdown on unapproved GLP-1 products sold direct to consumers.
FDA - press announcement: 30 telehealth companies warned over compounded GLP-1 marketing FDA · primaryThe broader enforcement wave around unapproved and compounded GLP-1 products.
Eli Lilly - retatrutide Phase 3 TRIUMPH results (investor release) analysisPositive Phase 3 results in obesity; investigational status confirmed by the sponsor.
Eli Lilly - what to know about retatrutide analysisLilly's own consumer-facing statement that retatrutide is investigational and not available outside trials/early access.
BioPharma Dive - Lilly, with new data, to seek FDA approval of retatrutide analysisReports the planned Q1 2027 BLA submission.
Camino Strategy Group - retatrutide and compounding: regulations and enforcement records analysisDocuments the December 2024 and March 2026 warning-letter waves, coded product names, and a state pharmacy-board enforcement record.
USADA - the WADA Prohibited List (S0: non-approved substances) analysisS0 prohibits substances with no regulatory approval for human therapeutic use at all times.

Last verified by a human: Aug 22, 2026 (ET) · how we verify
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