Compare · GLP-1 agonist
Retatrutide vs Tirzepatide
Both are glp-1 agonist compounds. Here's how they line up on the evidence — graded the same way.
| Retatrutide | Tirzepatide | |
|---|---|---|
| Evidence | Preliminary human | Strong human |
| Class | GLP-1 agonist | GLP-1 agonist |
| Summary | An investigational triple-hormone agonist with striking weight-loss data in trials, but not yet FDA-approved and with no peer-reviewed Phase 3 results. | A dual GIP/GLP-1 receptor agonist with strong RCT evidence for type 2 diabetes, weight loss, and sleep apnea; GI side effects are common. |
| Full profile → | Full profile → |
Retatrutide
Retatrutide (Lilly code LY3437943) is an investigational injectable drug for obesity and type 2 diabetes. It has produced some of the largest weight-loss figures seen in trials so far, but as of June 2026 it is not approved anywhere and its pivotal Phase 3 data have not yet been peer-reviewed.
Tirzepatide
Tirzepatide is a once-weekly injectable peptide sold as Mounjaro (for type 2 diabetes) and Zepbound (for weight management and sleep apnea). Unlike most compounds we cover here, it has been tested in large, well-run human trials, and the results are unusually consistent. This is not medical advice.