Lilly Says Its Experimental Weekly Injection Topped Ozempic's Highest Dose in a Diabetes Trial

Eli Lilly announced topline results on Oct. 28, 2026, from a head-to-head trial in which its experimental weekly injection retatrutide lowered blood sugar more than Ozempic's highest approved dose and produced more than twice as much weight loss in 1,298 adults with type 2 diabetes. The numbers are the company's own and have not been presented at a medical meeting or published in a journal.

Kenneth Custer, who leads Lilly's cardiometabolic health business, said trials that compare a new medicine directly against a treatment already in use show patients and doctors how it measures up against today's options. He said that, if approved, retatrutide "could shift the treatment paradigm for people living with type 2 diabetes, obesity and related cardiometabolic conditions."

By Lilly's own account in its release, retatrutide at either dose lowered A1C, a measure of average blood sugar, by 2.2% over 80 weeks. Semaglutide 2 mg, sold as Ozempic, lowered it by 1.8%. People on retatrutide lost an average of 44.3 pounds on the lower dose and 47.4 pounds on the higher one. Those on semaglutide lost 20.9 pounds.

The company said the trial, called TRANSCEND-T2D-2, enrolled adults whose diabetes was not controlled by metformin alone, and tested retatrutide at 9 mg and 12 mg. The trial was open-label, meaning everyone knew which drug they were getting, and its stated aim was to show the higher retatrutide dose was no worse than semaglutide at lowering A1C.

Lilly also reported that stomach and bowel problems were the most common side effects on retatrutide, that most were mild to moderate, and that more people stopped treatment because of side effects on retatrutide than on semaglutide.

Lilly said retatrutide is not approved by the Food and Drug Administration or any other regulator and cannot legally be sold. The company said detailed results from the trial will be presented at a future medical meeting and published in a peer-reviewed journal.

Lilly said it is also studying retatrutide in obesity, sleep apnea and knee osteoarthritis pain, and is running a separate trial comparing it with tirzepatide, sold as Mounjaro.