Region — International. Neutral scientific reference — not offered for sale here.
Research reference — not for sale
Retatrutide
Blead outcome
Weight loss (obesity)
grades vary by outcome ↓
Peptide
also called — retatrutide · LY3437943 · GLP-1 / GIP / glucagon triple agonist · "triple-G" · investigational (Eli Lilly). INCI: none · GLP-3-RT
metabolicobesity / weighttype-2 diabetes (investigational)
Reference entry — NOT a sellable lane, and NOT approved anywhere. Retatrutide is the sharpest "demand-outruns-approval" case in the register: genuinely spectacular trial data, but an investigational drug with zero legal sellable pathway. The "research-use-only" retatrutide sold gray-market is unregulated and is not the trial compound. No dosing published here.
In brief
Retatrutide is Eli Lilly's investigational triple GLP-1/GIP/glucagon agonist ("triple-G"), which in Phase 3 (TRIUMPH-1) produced the deepest weight loss of any obesity candidate to date (~28–30%). The evidence is genuinely strong and trending toward approval — but it is not approved anywhere, the Phase 3 programme is still completing, and the "research-use-only" retatrutide sold online is unregulated and not the studied product.
Legal standing, by region
- Everywhere — investigational, NOT approved. No FDA, no EMA, no approved prescription pathway; all legitimate use is within Lilly's clinical trials.
- Gray market: "research-use-only" retatrutide is widely sold but unapproved and unregulated — unknown purity, sterility, and dosing accuracy; it is not the trial compound.
- This venture: not a sellable lane — an investigational drug; gray-market sale is illegal and unsafe.
- Sport: an investigational incretin-class agent; not a listed performance category, but athletes under testing should verify current status.
An honest grade per outcome — drawn from the evidence, not any catalogue. Hype and undemonstrated marketing claims grade low.
OutcomeEvidence base · effectGrade
Weight loss (obesity)
Phase 3 topline is positive, but not yet approved; full peer-reviewed Phase 3 data + regulatory review pending
Phase 2 (NEJM 2023, 24.2%/48wk) + Phase 3 TRIUMPH-1 topline (28.3%/80wk) · Deepest weight loss of any obesity candidate to date
BType-2 diabetes glycemic control
Topline only; not approved
Phase 3 TRANSCEND-T2D-1 topline (≤2.0% A1C, ~16.8% weight, 40wk) · Strong
BHepatic fat / energy expenditure (the glucagon arm)
The arm neither semaglutide nor tirzepatide has; long-term effects still being characterised
Mechanistic + trial signals · Promising / distinguishing
CSafety / long-term
Long-term and glucagon-arm safety being established in Phase 3; gray-market product safety is unknown
Phase 2/3 (incretin-class GI AEs, mostly mild-moderate on escalation) · GI-predominant
—Disclosure
Vallydia sells its own cosmetic serums, and some ingredients graded here belong to the same categories as those products. Grades are drawn from the published evidence by the method we publish, and applied to our own ingredients on the same terms — our copper-peptide serum is graded no more kindly than the peptides it competes with. We disclose the interest so you can weigh it.
Trade names shown here (for example Matrixyl, Argireline, Syn-Ake) are the property of their respective owners and are used only to identify the ingredient under discussion. Their appearance implies no affiliation with, or endorsement by, the proprietor.
Evidence changes
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Identity
a single engineered synthetic peptide that activates three receptors — GLP-1, GIP, and glucagon — once weekly. The first triple agonist to reach Phase 3. (Semaglutide is a GLP-1 mono-agonist; tirzepatide is a GLP-1/GIP dual agonist; retatrutide adds the glucagon arm.)
Mechanism (as proposed)
a single peptide acting as a triple agonist — GLP-1 (appetite suppression, slowed gastric emptying) + GIP (insulinotropic, satiety) + glucagon (raises basal energy expenditure and reduces hepatic fat). Lilly attributes the unusually deep weight loss partly to adding glucagon agonism on top of the GIP/GLP-1 pathways.
Sources — 2 cited
01Jastreboff AM, et al. Triple-hormone-receptor agonist retatrutide for obesity — a Phase 2 trial. N Engl J Med. 2023.
02Eli Lilly — TRIUMPH-1 Phase 3 topline (21 May 2026); TRANSCEND-T2D-1 topline (19 Mar 2026); TRIUMPH programme design (Diabetes Obes Metab, 2026).
Updated 2026-07-13 (fast-moving — re-check TRIUMPH-2/-3 readouts and any regulatory filing)
Grades reflect the published evidence, not our interest. No dosing, reconstitution, or administration is published for research compounds — that restraint is deliberate.
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Region — International
This site provides neutral scientific reference and sells only products lawful in your region. Nothing here is medical advice, a recommendation, or an offer to supply unapproved medicines. No dosing or administration is published for research compounds. Cosmetic peptides per Regulation (EC) 1223/2009. Unapproved injectable peptides are neither sold nor advertised in the EU (Directive 2001/83/EC, Title VIII). © 2026 Vallydia.