This article is for educational and informational purposes only. Retatrutide is an investigational drug currently in Phase 3 clinical trials. It is NOT approved by the FDA or any regulatory authority for any use. It should not be purchased, obtained, or used outside of official clinical trials. Do not use any investigational compound without medical supervision.
Retatrutide is an investigational drug being studied as a possible new medication to help people lose weight and improve blood-sugar control. It is made by Eli Lilly — the same pharmaceutical company that created Mounjaro (tirzepatide) and Zepbound.
Retatrutide is currently in Phase 3 clinical trials. This means it has passed initial safety screening and showed promising results in early studies, but it has not yet been approved for use. No one outside of an official, supervised clinical trial should have access to or use this compound.
Reduces appetite and slows stomach emptying. Shared with semaglutide and tirzepatide.
Enhances insulin response and complements GLP-1 action. Also targeted by tirzepatide.
Boosts energy expenditure and fat breakdown. Unique to Retatrutide among approved or near-approved drugs.
Compare: Semaglutide targets one switch. Tirzepatide targets two. Retatrutide targets all three — which may explain its stronger early weight-loss signal.
GLP-1 only
~15%
GLP-1 + GIP
~20%
GLP-1 + GIP + Glucagon
~24%
In a Phase 2 clinical trial published in The New England Journal of Medicine (2023), adults taking Retatrutide for approximately 48 weeks lost, on average, about 24% of their body weight — a striking result that exceeded prior drug classes.
Note: Because Retatrutide also targets glucagon receptors, researchers monitor for small increases in resting heart rate and changes in liver enzymes. These have not been serious so far, but larger studies will reveal the full safety profile.
Retatrutide is currently advancing through Phase 3 trials — the largest and most rigorous stage of the clinical development process. Phase 3 trials typically involve thousands of participants and track both efficacy and long-term safety across diverse populations.
Even if Phase 3 results are positive, the journey to FDA approval — manufacturing scale-up, regulatory review, labeling, pricing — means Retatrutide could be several years away from reaching patients, even in an optimistic scenario.
| Authors | Year | Journal | Key Findings |
|---|---|---|---|
| Jastreboff et al. | 2023 | New England Journal of Medicine | Phase 2 trial: up to 24.2% body weight loss at 48 weeks; improved metabolic markers |
This article is for educational and informational purposes only. Retatrutide is an investigational drug currently in Phase 3 clinical trials. It is NOT approved by the FDA or any regulatory authority for any use. It should not be purchased, obtained, or used outside of official clinical trials. Do not use any investigational compound without medical supervision.
