The Triple-Agonist Drug Showing Up to 24% Weight Loss in Clinical Trials
Medical Disclaimer: Retatrutide is an investigational drug not yet approved by the FDA. This content is for educational purposes only. Consult a healthcare provider before making any medication decisions.
Retatrutide is an investigational "triple agonist" weight loss medication being developed by Eli Lilly. Unlike current GLP-1 medications that target one or two receptors, retatrutide activates three:
Reduces appetite and slows gastric emptying
Enhances insulin secretion and may improve fat metabolism
Increases energy expenditure and promotes fat breakdown
This triple-action mechanism produced some of the largest average weight-loss results reported in obesity trials, with participants on the highest dose losing about 24% of their body weight at 48 weeks in a phase 2 study.
Retatrutide completed Phase 2 trials with impressive results and is now in Phase 3 trials. It is NOT yet FDA-approved and is NOT commercially available. All information on this page comes from published clinical trial data.
Retatrutide has produced some of the most impressive weight loss results ever seen in obesity trials. In the Phase 2 trial published in the New England Journal of Medicine:
Eli Lilly's TRIUMPH Phase 3 program is now testing retatrutide in larger populations. Early Phase 3 data suggests even greater weight loss (up to ~29%) over longer treatment periods. FDA approval could come as early as late 2025 or 2026 if trials are successful.
Gastrointestinal side effects such as nausea, diarrhea, vomiting, and constipation were common in trials and increased with higher doses. These effects were typically:
This side effect profile is similar to other GLP-1–based medications like semaglutide and tirzepatide. The gradual dose titration approach used in trials helped minimize these effects.
The slow titration approach helps minimize these effects.
| Medication | Receptor Targets | Max Weight Loss |
|---|---|---|
| Retatrutide | GLP-1 + GIP + Glucagon | ~24% at 48 weeks |
| Tirzepatide (Zepbound) | GLP-1 + GIP | ~22% at 72 weeks |
| Semaglutide (Wegovy) | GLP-1 only | ~15% at 68 weeks |
Retatrutide's added glucagon receptor activity is hypothesized to contribute to greater energy expenditure and fat loss, which may help explain the larger average weight loss seen at high doses in trials. However, this also appears to come with more gastrointestinal side effects at those doses.
Compare Tirzepatide vs Retatrutide in DetailDetailed titration schedules, dose levels, and injection information from clinical trials.
View dosing detailsExpected pricing, insurance coverage prospects, and cost comparisons with current options.
View cost infoCurrent availability, clinical trial enrollment, and when it might become commercially available.
View availabilityRetatrutide isn't available yet, but several effective options exist today:
Compounded Tirzepatide
$297/month
Check EligibilityCompounded Semaglutide
$199/month
Check EligibilityBrand Wegovy/Zepbound
$349+/month
Check EligibilityWe'll notify you when retatrutide receives FDA approval, pricing is announced, and providers start offering it.
