Retatrutide research initially attracted attention because of the amount of weight participants lost. But the Phase 3 research program is increasingly asking a different question: What happens to the health conditions associated with obesity when body weight falls by 20%, 25%, or even more? By mid-2026, retatrutide had produced reported improvements in several areas beyond … Read more
Glucagon has traditionally been associated with one thing: raising blood glucose. So it can sound counterintuitive that retatrutide, a molecule being studied for obesity and type 2 diabetes, was deliberately designed to activate the glucagon receptor. That receptor activity is not an accidental side effect. It is one of the defining features of retatrutide. Retatrutide, … Read more
TLDR Retatrutide has now produced significant improvements in both glycemic control and body weight in peer-reviewed Phase 2 and Phase 3 trials involving people with type 2 diabetes. The 2023 Phase 2 study found A1C reductions of about 2 percentage points at the higher doses and weight loss approaching 17% after 36 weeks. The evidence … Read more
Updated September 4, 2026 Retatrutide is no longer a drug candidate supported by one or two promising trials. Eli Lilly has built a broad clinical development program around the investigational triple hormone receptor agonist, testing it across obesity, type 2 diabetes, cardiovascular disease, chronic kidney disease, obstructive sleep apnea, knee osteoarthritis, chronic low back pain, … Read more
Retatrutide’s Phase 3 results are now large enough that one number no longer describes the drug. Depending on which trial you look at, the highest-dose retatrutide group lost an average of about 20.8%, 22.6%, 28.3%, or 28.7% of body weight. Those differences are not contradictions. They come from four trials that studied very different people. … Read more
Retatrutide has now been studied in thousands of people across Phase 2 and Phase 3 clinical trials. That gives researchers a much clearer picture of its safety profile than was available when the first obesity results appeared in 2023. The most consistent finding is not surprising: gastrointestinal side effects are the most common adverse events, … Read more
Large reductions in body weight almost never come entirely from body fat. Some fat-free mass is usually lost as well. That has made muscle loss an important question for newer incretin-based drugs, especially retatrutide, which has produced particularly large weight reductions in clinical trials. The good news is that researchers now have direct body-composition data … Read more
