ECO2025: Tirzepatide Wins on Weight and Cardiometabolic Data

This is quite a day for the folks who have invested energy and others who have invested a great deal of money into developing tirzepatide for obesity. They took the risk of doing a head-to-head study of this drug against semaglutide and it clearly paid off. In the SURMOUNT-5 study, tirzepatide came out ahead on both weight and cardiometabolic outcomes. On weight, the outcome was 47% better. That’s big. But also, tirzepatide produced clearly better outcomes on parameters of cholesterol, blood pressure, and glucose control.

Today, the New England Journal of Medicine published the full results of this study. Lead author Lou Aronne summed it up clearly and succinctly:

“You can see that the semaglutide results were quite good. The tirzepatide results were better.”

We love it when results are this clear and crisp – especially with such clear articulation.

More of the Roller Coaster Ride

Recent days have been quite a roller coaster ride for tirzepatide and its maker, Eli Lilly and Company. Eleven days ago their competitor, Novo Nordisk, seemed to have the upper hand with the announcement that the biggest PBM in America, CVS Caremark, was giving semaglutide preferred status on its benchmark formulary. That would make it tough for people to get access to tirzepatide.

Lilly’s stock dropped by 11% on that bit of news. But now, this gives Lilly bragging rights

This will not be the end of it. People living with obesity are ticked that the Caremark PBM is trying to deny them access to the most effective drug available (for now) to treat obesity. A Change.org petition is out there to tell them to cut it out. It’s wrong and people clearly don’t like PBMs jerking them around.

We sympathize and this news, that tirzepatide yields better weight and cardiometabolic outcomes, will simply add fuel to the fire. The competition will get hotter.

Click here for the NEJM publication, here for further reporting, and here for Aronne presenting the results.

Spanish Ibex on the El Torcal rocks in the province of Málaga, photograph by Tuxyso, licensed under CC BY-SA 3.0

Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.

May 12, 2025