20.9% weight loss with retatrutide in trial comparing Lilly drug with Ozempic
Key Facts
Eli Lilly on October 28 announced positive preliminary results from the Phase 3 TRANSCEND-T2D-2 trial, which compared the investigational drug retatrutide with Ozempic injections at a 2 mg dose in adults with type 2 diabetes. After 80 weeks, average weight loss was 20.9% with the 12 mg retatrutide dose, compared with 9.4% with Ozempic. The 9 mg retatrutide dose recorded weight loss of 19.5%. The results also showed an average reduction in HbA1c of 2.2% with both retatrutide doses, compared with 1.8% with Ozempic. The trial provides a direct comparison between the investigational drug and the Ozempic dose used in the study, while the results remain preliminary, according to the company’s announcement.
The trial included 1,298 adults whose diabetes was not adequately controlled with metformin, with or without an SGLT2 inhibitor. Average weight at the start of the study was 102.4 kg, while average body mass index was 36.8 kg/m². The study tested retatrutide doses of 9 and 12 mg against Ozempic at a 2 mg dose. These figures place the weight-loss results among participants with type 2 diabetes, rather than in a general weight-loss trial. Lilly said the measurements reported in the results were taken at week 80 of the trial.
The greater reductions in weight and HbA1c came alongside higher rates of treatment discontinuation due to side effects with both retatrutide doses. A total of 4.8% of those receiving the 9 mg dose stopped treatment for this reason, compared with 7.9% with the 12 mg dose. The rate was 2.7% among those receiving Ozempic. Lilly said gastrointestinal disorders were among the common side effects. This difference adds a tolerability dimension to the comparison of efficacy results, as discontinuation rates varied between the two investigational doses and the comparator drug.
Retatrutide remains an investigational drug and has not been approved by the U.S. Food and Drug Administration or any regulatory body worldwide, according to Lilly. The company said detailed results would be presented at a future medical meeting and published in a peer-reviewed journal, without specifying a date in its announcement. Lilly is also conducting a Phase 3 trial directly comparing retatrutide with tirzepatide in adults with obesity, whether or not they have type 2 diabetes. The trial is called TRIUMPH-5, according to the company. Its anticipated results remain separate from the preliminary data announced in the TRANSCEND-T2D-2 trial.
The trial results were announced ahead of Lilly’s third-quarter results on October 29, when it said global revenue was $24.397 billion, up 39% year over year. The company raised the midpoint of its 2026 revenue forecast by $5.5 billion, to a range of $91.0 billion to $92.0 billion. At the October 30 closes, Novo Nordisk shares stood at $40, compared with $39.14 in the previous session. Lilly shares closed at $1,417.54, after $1,373.7 on October 29. The closing data show both shares rose between the sessions, without identifying on their own the reason for their moves.
The new comparison comes amid the race for obesity drugs, where competition is not limited to the result of a single trial. In August, Novo Nordisk’s chief executive said investors were underestimating how patients’ needs differ from one treatment to another, and that the obesity-drug market would not necessarily be a winner-takes-all contest. He said at the time that the company was targeting a launch of its investigational drug CagriSema the following year. An earlier story published by EL7 on September 22 also covered CagriSema results compared with Lilly’s Zepbound. That comparison provides further context for tracking the two companies’ programs, while the current retatrutide result remains tied to the patients with diabetes who participated in the trial.