Lilly's New Drug Yields Dramatic Weight Loss, Rivaling Bariatric Surgery, GLP-1s

Eli Lilly recently announced phase 3 trial results for a promising new weight loss drug retatrutide. The dramatic results from the TRIUMPH-1 trial represent the greatest weight loss observed in a medication trial, rivaling current GLP-1 drugs and bariatric surgery. Retatrutide is a triple hormone receptor agonist that activates receptors for glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon.

Retatrutide led to significant improvements across various cardiovascular risk factors, including waist circumference, cholesterol, and blood pressure. Eli Lilly’s new experimental weight loss drug retatrutide showed the greatest weight loss in a medication trial to date. The phase 3 results of the TRIUMPH-1 trial showed the drug yielded up to 28% weight loss, with some participants losing up to 85 pounds. Retatrutide is a triple hormone agonist administered by once-weekly injection. The drug activates glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon, whereas weight loss drugs like Ozempic and Wegovy activate only the GLP-1 receptor. Lilly noted in a press release that at 80 weeks, all the doses of retatrutide “met the primary and key secondary endpoints for obesity, delivering clinically meaningful weight loss.” “TRIUMPH-1 highlights the importance of options and the potential for retatrutide to help people across various stages of their obesity journey,” Kenneth Custer , PhD, executive vice president and president, Lilly Cardiometabolic Health, said in a press release . “Together with Zepbound and Foundayo, retatrutide could build on Lilly’s commitment to match treatments to the needs and preferences of patients.” Experts agreed that retatrutide shows promise as a highly effective first-in-class treatment for obesity. “These results indicate that retatrutide is a promising new drug that appears more effective than currently available medications,” said Mir Ali , MD, bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA. Ali wasn’t involved in the trial. In the TRIUMPH-1 trial, participants were given either 4 mg, 9 mg, or 12 mg of retatrutide. At the end of 80 weeks, participants on each dose lost the following amount of weight on average: These numbers compare to participants who received a placebo and lost an average of 2.2%, or about 5.5 lbs. At 104 weeks, participants with a baseline body mass index (BMI) of at least 35 achieved an average weight loss of 30.3% (85 lbs) .

Key points

• Retatrutide led to significant improvements across various cardiovascular risk factors, including waist circumference, cholesterol, and blood pressure.
• Eli Lilly’s new experimental weight loss drug retatrutide showed the greatest weight loss in a medication trial to date.
• The phase 3 results of the TRIUMPH-1 trial showed the drug yielded up to 28% weight loss, with some participants losing up to 85 pounds.
• Retatrutide is a triple hormone agonist administered by once-weekly injection.
• The drug activates glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon, whereas weight loss drugs like Ozempic and Wegovy activate only the GLP-1 recep…