Eli Lilly reported record results for its new anti-obesity drug, with weight loss of up to 28.7% in the completed study.
In the 68-week study, the highest dose of Retatrutide resulted in an average weight loss of 23.7% when all participants were included, even those who discontinued treatment. Among patients who completed therapy, the average weight loss was 28.7%. Eli Lilly said some patients dropped out because of the loss “excessive” in weight, writes the News.
The TRIUMPH-4 study is the first advanced phase for retatrutide, considered the future strategic pillar of the Lilly portfolio in obesity therapy, after the Zepbound injection. The drug works by mimicking three hormones that regulate appetite, GLP-1, GIP and glucagon, a mechanism that seems to generate stronger effects than existing treatments.
In addition to remarkable weight loss, retatrutide reduced knee osteoarthritis pain by up to 62.6% on average, and more than one in eight patients reported no pain at all at the end of the study.
A sensitive point for modern antiobesity therapies is the loss of muscle mass. However, the consulted specialists emphasized that patients with severe obesity showed improvements in physical function.
Adverse reactions were notable, however: at the maximum dose, 18% of patients discontinued treatment due to side effects, a figure similar to that observed in the Zepbound and Wegovy trials for patients with very high BMI. The most common effects included nausea (43%), diarrhea (33%) and vomiting (20.9%), as well as dysesthesia, an unpleasant sensation in the nerves.
The results beat analysts’ expectations, and Eli Lilly shares rose more than 3% after the announcement. The company estimates that retatrutide may become an important option for patients with severe obesity and associated complications.
Eli Lilly will publish the results of seven more major clinical trials by the end of 2026, which will clarify the full profile of the drug.
Meanwhile, Novo Nordisk is working on a similar experimental treatment, recently acquired from China, but it is in an early stage of development and will not reach the market for several years.
