New research suggests people lose more weight when taking tirzepatide – the drug in Zepbound and Mounjaro – than when using semaglutide – the drug in Wegovy and Ozempic.
The study, published Monday in JAMA Internal Medicine, compared medical data from 18,000 U.S. adults who were overweight or obese and taking either tirzepatide or semaglutide for the first time. The “…use of tirzepatide was associated with significantly greater weight loss than semaglutide,” according to the researchers.
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Within 12 months, approximately 82% of adults taking tirzepatide lost 5% or more of their body weight compared to approximately 67% of adults taking semaglutide. More than 42% of people taking tirzepatide had 15% or greater weight loss than the approximately 18% taking semaglutide.
Tirzepatide is produced by Eli Lilly and sold under the brand names Zepbound for weight loss and Mounjaro for diabetes treatment. Semaglutide is manufactured by Novo Nordisk and sold as Wegovy for weight loss and Ozempic for diabetes treatment.
Similar to findings in other studies, the new research suggest that people on these medications who had obesity and diabetes lost less weight than those without diabetes.
The average age of participants in the study was 52 and 70% were female, 77% were white and 11% were Black. The participants started taking one of the two medications between May 2022 and September 2023.
“Future work is needed to compare the effect of tirzepatide and semaglutide on other key end points,” including the drugs’ potential to reduce major cardiovascular events, researchers said.