Investigational Weight-Loss & Metabolic Peptide
Retatrutide
LY3437943 · GGG tri-agonist · "triple G" peptide
Also known as the "triple-G" peptide
An investigational triple-receptor agonist (GLP-1 · GIP · glucagon) studied for weight management.
Retatrutide (research code LY3437943) is an investigational medicine being developed by Eli Lilly and studied in clinical trials for chronic weight management and related metabolic conditions. It is often described as a "triple agonist" because, unlike GLP-1 medicines such as semaglutide or the dual GLP-1/GIP medicine tirzepatide, it is designed to act on three different receptors at once. It is important to know that retatrutide is still investigational — it has not been approved by the U.S. FDA and is not sold or prescribed through Rx.com today.
What Retatrutide is being researched for
People most often look into Retatrutide in connection with the areas below. These are research directions — not approved or proven treatments.
- Chronic weight management research
- Type 2 diabetes research
- Metabolic & cardiometabolic health
- Non-alcoholic fatty liver disease (NAFLD) research
- Obesity-related condition research
What is retatrutide?
Retatrutide is an experimental peptide medicine in the same broad family as today's GLP-1 weight-loss and diabetes drugs, but with a wider mechanism. Where Ozempic and Wegovy (semaglutide) act mainly on the GLP-1 receptor, and Mounjaro and Zepbound (tirzepatide) act on both GLP-1 and GIP, retatrutide is being studied as a single molecule that targets three hormone pathways. It is given as a weekly under-the-skin injection in clinical trials.
How is retatrutide thought to work?
Retatrutide is designed to activate three receptors involved in appetite, blood sugar, and energy use: GLP-1 (helps reduce appetite and slow stomach emptying), GIP (involved in insulin and fat handling), and glucagon (involved in how the body burns stored energy). Researchers are studying whether combining all three could affect weight and metabolism. These are research directions, and results in trials do not guarantee how an approved product would perform or be dosed.
What have clinical trials shown?
In published mid-stage (Phase 2) research, participants taking higher doses of retatrutide experienced substantial average weight reduction over roughly a year compared with placebo, and separate trials have explored its effects in type 2 diabetes and fatty liver disease. Larger Phase 3 trials are ongoing to confirm how well it works and how safe it is. As with all GLP-1-type medicines, reported side effects were most often digestive (such as nausea). Trial findings are reported here for education only and are not a promise of results.
Is retatrutide FDA approved or available?
No. Retatrutide is not FDA approved and is not available to purchase or be prescribed through Rx.com. It remains an investigational drug in clinical development. If it earns FDA approval in the future, Rx.com plans to help eligible patients compare prices and access it safely. In the meantime, several FDA-approved weight-management medicines already exist, and a licensed provider can help you understand your options.