Retatrutid · DOSSIER

Retatrutid

Retatrutide · LY3437943
LEGAL DE · NOT APPROVEDEVIDENCE · EARLY CLINICAL STUDIES2 STUDIES
SUMMARY

In a Phase II study (n=338), participants lost up to 17.5% of their body weight over 24 weeks.

FIG.01 — SIGNAL CHAIN
EVIDENCE LEVELSPROVEN IN HUMANSANIMAL MODELS ONLYMECHANISM ONLYUNPROVEN IN HUMANS
01

What it does in the body

Findings, each with its evidence level — animal data kept visibly apart from what's unproven in humans.

Up to 17.5% weight loss

In a Phase II study (n=338), participants lost up to 17.5% of their body weight over 24 weeks.

PROVEN IN HUMANS
Appetite down

As a GIP/GLP-1 agonist it dampens the hunger signal — the same pathway as semaglutide and tirzepatide.

MECHANISM ONLY
Metabolism up

The added glucagon activation is intended to raise basal metabolism and hepatic fat breakdown.

MECHANISM ONLY
Not yet approved

Phase III (the TRIUMPH programme) is ongoing; long-term safety and cardiovascular endpoints are pending.

UNPROVEN IN HUMANS
02

Mechanism of action

What Retatrutid does in the body — step by step.

01

Retatrutide is a triple agonist at GIP, GLP-1 and glucagon receptors (GGG agonist).

02

The additional activation of the glucagon receptor compared with dual GIP/GLP-1 agonists such as tirzepatide is intended to increase basal metabolic rate and intensify hepatic fat metabolism.

03

Eli Lilly developed the peptide with the aim of addressing all three incretin receptors simultaneously.

03

Research status

How far along is the evidence?

PRECLINICALEARLY CLINICAL STUDIESCLINICALLY ESTABLISHED
Retatrutide is in clinical development.
Retatrutide is in clinical development.
A Phase II study (2023, n=338) investigated various doses over 24 weeks in obesity and observed weight reductions of up to 17.5% of baseline weight — numerically above the values observed for semaglutide or tirzepatide in comparable Phase II studies.
Phase III studies (the TRIUMPH programme) have been started; results are pending.
Long-term safety and cardiovascular endpoints have not been conclusively investigated.
04

Known risks

Without human data, safety statements are limited. What is known:

01
Safety profile not conclusively established — no completed Phase III data
02
Gastrointestinal side effects (nausea, vomiting, diarrhoea) frequently described in Phase II studies
03
Glucagon agonism could promote blood-sugar instability in diabetics
04
Heart rate increase possible under glucagon agonism
05
Gallbladder complications with rapid weight loss
06
Interactions with other blood-sugar-lowering medications not fully characterised
07
No long-term safety data available
05

Cited studies

Chronological — links lead to the source.

2023
Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes: a randomised, double-blind, placebo- and active-controlled, parallel-group, phase 2 trial
PubMed 37366315 →
2023
Retatrutide for Obesity — Two Phase 2 Trials
PubMed 37366143 →
06

Frequently asked questions

What is Retatrutid?+

Retatrutide is a triple agonist at GIP, GLP-1 and glucagon receptors (GGG agonist).

What type of peptide is Retatrutid?+

Retatrutid belongs to the GLP-1 analog class.

What is Retatrutid used for?+

In research, Retatrutid has primarily been investigated in the context of: Metabolism. These are research findings (evidence: early clinical studies), not proven benefits in humans and not a usage recommendation.

Is Retatrutid legal in Germany?+

Retatrutid is not approved as a medicine in Germany. Obtaining it outside clinical studies is legally problematic.

Is Retatrutid FDA-approved / legal in the US?+

No. Retatrutid is not FDA-approved as a drug in the US; it is mostly sold as a research chemical and not for human consumption.

Is Retatrutid legal in Canada?+

No. Retatrutid is not authorized by Health Canada and not intended for human consumption.

Where can I buy Retatrutid?+

Peptica sells nothing and names no sources. Retatrutid is "not approved" in Germany; obtaining unapproved substances outside clinical studies is illegal and carries quality and safety risks.

What is the dosage of Retatrutid?+

Peptica publishes no dosing. There are no approved dosing guidelines for Retatrutid; figures circulating online stem from animal studies or anecdote, not from validated human protocols. This is not medical advice.

Is Retatrutid banned in sport (WADA)?+

Retatrutid is currently not on the WADA Prohibited List.

What are the known risks of Retatrutid?+

Documented risks include: Safety profile not conclusively established — no completed Phase III data; Gastrointestinal side effects (nausea, vomiting, diarrhoea) frequently described in Phase II studies. This is not a complete safety assessment and not medical advice — see the risks section for the full list.

How well researched is Retatrutid?+

The evidence is classified as “early clinical studies”. 2 studies are cited on this page.

What is the molecular weight of Retatrutid?+

Retatrutid has a molar mass of about 4731.33 Da, with a plasma half-life of ~6 days.

Which peptides are related to Retatrutid?+

Closely related entries: Tirzepatid, Semaglutid. A direct side-by-side comparison is available via the compare function.

07

Dossier

Legal · Structure · Sources.

LEGAL STATUS BY REGION
Germanynot approved

Retatrutide does not yet have market approval in the EU, Germany or Switzerland. Phase III studies are ongoing; a possible approval submission to the EMA and FDA is expected in 2026/2027 at the earliest. Obtaining it as a research chemical outside clinical studies is illegal and carries considerable safety risks.

Legal status varies by country and can change. This is not legal advice.

SOURCES & EXTERNAL DATABASES

Methodology: Peptica compiles publicly available studies and regulatory information and assigns each statement an evidence level. Not medical advice. No warranty.

RELATED PEPTIDES & FURTHER READING
08

Community notes

Note: These posts are user opinions and not medical advice. Posts containing dosages, therapeutic claims or purchase recommendations are removed. All entries are manually reviewed before publication.
This page is intended solely for factual, scientifically oriented information. No medical advice · no dosage or usage recommendations · no claims of efficacy · no substitute for medical consultation. Peptica sells no substances. Partner links are marked as advertising; Peptica may earn a commission. © 2026 Peptica · Issue 01