Peptide library / Digestive & weight / Retatrutide
Retatrutide
An investigational once-weekly triple agonist of the GIP, GLP-1 and glucagon receptors from Eli Lilly.
Effects studied or claimed
What it is used or promoted for, and where each effect has actually been seen
- Weight loss in obesityLarge trials
- Blood sugar control in type 2 diabetesLarge trials
- Fatty liver diseaseSmall human studies
How it is thought to work
Retatrutide adds glucagon receptor activity to the GIP and GLP-1 mechanism of tirzepatide, which may raise energy expenditure and reduce liver fat in addition to cutting appetite.
What the evidence shows
In a phase 2 trial in adults with obesity, the highest dose produced average weight loss of about 24 percent at 48 weeks, the largest figure reported for a peptide drug at that time. Phase 3 trials in the TRIUMPH program are under way, and the sponsor has begun reporting results.
Safety and unknowns
Gastrointestinal effects were the most common. Heart rate increases and skin sensation changes were also noted in early studies. Long-term safety is not yet established.
Regulatory status
Not approved anywhere at the time of writing. Check ClinicalTrials.gov for the current phase 3 status.
Regulatory status changes quickly. This entry was last reviewed on 27 October 2026. Confirm current status with the FDA before relying on it.
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General information, not medical advice. Do not buy or inject unregulated peptides.