# Retatrutide

> Investigational triple agonist (GIP / GLP-1 / glucagon) in late-stage trials.

- Also known as: LY3437943
- Class: Metabolic
- FDA approved: No
- Canonical page: https://www.americanpeptide.com/catalog/retatrutide

## Overview

Retatrutide is an Eli Lilly–developed triple agonist targeting GIP, GLP-1, and glucagon receptors. Phase 2 trials reported ~24% mean weight reduction at 48 weeks at the highest dose.

Retatrutide (development code LY3437943) is an investigational single peptide that activates three receptors — GIP, GLP-1, and glucagon. Adding glucagon-receptor agonism to the incretin pair is studied as a way to increase energy expenditure and lipolysis on top of the insulinotropic and satiety effects of GIP and GLP-1.

Developed by Eli Lilly, it remains investigational and has not been approved. Phase 2 results reported notably large mean weight reductions at the highest doses over roughly a year, placing it among the most closely watched "triple agonist" candidates in late-stage metabolic research.

## Mechanism

GIP + GLP-1 (insulinotropic, satiety) plus glucagon (energy expenditure, lipolysis).

## Chemistry

| Property | Value |
| --- | --- |
| Molecular formula | C221H342N46O68 |
| Molecular weight | 4731.5 Da |
| PubChem CID | [171390338](https://pubchem.ncbi.nlm.nih.gov/compound/171390338) |

## Research areas

Studied in: Obesity, Type 2 diabetes, MASH.

Guides on this site:

- [Weight Loss & Metabolic Health](https://www.americanpeptide.com/research-areas/weight-loss): Incretin and metabolic peptides studied for glycemic control and fat loss.

## Key research

- Triple agonism — combines GIP/GLP-1 (insulin, satiety) with glucagon (energy expenditure, lipolysis).
- Weight reduction — Phase 2 trials reported among the largest mean reductions seen for an investigational agent.
- Type 2 diabetes — studied for glycemic endpoints alongside weight.
- MASH / hepatic fat — examined as a metabolic-liver-disease endpoint.
- Investigational status — not approved; under continued clinical evaluation.

## FAQs

### What is retatrutide?

Retatrutide is an investigational triple agonist targeting the GIP, GLP-1, and glucagon receptors, studied in late-stage trials for obesity and type 2 diabetes.

### How does a triple agonist differ from dual or single agonists?

It adds glucagon-receptor activation — studied for increased energy expenditure and fat breakdown — to the insulinotropic and satiety effects of GIP and GLP-1.

### Is retatrutide approved?

No. It is investigational and has not received FDA approval; all data comes from clinical research.

### Who develops retatrutide?

Eli Lilly. This page is a research and educational reference, not medical advice or an offer for sale.

## Latest research

Recent trials and publications mentioning Retatrutide, pulled automatically from ClinicalTrials.gov and PubMed (unfiltered search results, refreshed daily).

### Recent trials

- [A Study to Investigate the Response of Participants With Type 2 Diabetes Mellitus on Once-Weekly Retatrutide to Hypoglycemia](https://clinicaltrials.gov/study/NCT06982846) — COMPLETED · PHASE1 · NCT06982846
- [The Effect of Retatrutide Once Weekly on Cardiovascular Outcomes and Kidney Outcomes in Adults Living With Obesity (TRIUMPH-Outcomes)](https://clinicaltrials.gov/study/NCT06383390) — ACTIVE_NOT_RECRUITING · PHASE3 · NCT06383390
- [A Study of Retatrutide (LY3437943) in Participants Without Type 2 Diabetes Who Have Obesity or Overweight](https://clinicaltrials.gov/study/NCT07357415) — ACTIVE_NOT_RECRUITING · PHASE3 · NCT07357415
- [Provide Pre-approval Expanded Access of LY3437943](https://clinicaltrials.gov/study/NCT07629401) — AVAILABLE · NCT07629401
- [A Master Protocol of Multiple Agents in Adults With Metabolic Dysfunction-Associated Steatotic Liver Disease (SYNERGY-Outcomes)](https://clinicaltrials.gov/study/NCT07165028) — RECRUITING · PHASE3 · NCT07165028
- [A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight](https://clinicaltrials.gov/study/NCT05929066) — COMPLETED · PHASE3 · NCT05929066

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Source: AmericanPeptide.com — https://www.americanpeptide.com/catalog/retatrutide
Data license: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Attribution: AmericanPeptide.com.
Research reference only — computational and educational content, not medical advice.