MONDAY, July 8, 2024 (HealthDay News) -- Mounjaro outperforms Ozempic in helping people lose weight, a new study shows.

People taking tirzepatide (Mounjaro, Zepbound) dropped significantly more pounds than those taking semaglutide (Ozempic, Wegovy), researchers reported July 8 in the journal JAMA Internal Medicine.

“Individuals with overweight or obesity treated with tirzepatide were significantly more likely to achieve clinically meaningful weight loss and larger reductions in body weight compared with those treated with semaglutide,” concluded the research team led by Dr. Nicholas Stucky, vice president of research with Truveta Inc., a medical research collective.

For the study, researchers tracked more than 18,000 overweight and obese people who were prescribed either drug to help control their type 2 diabetes between May 2022 and September 2023.

Both drugs initially were developed as type 2 diabetes medications, but were later approved for use in weight loss.

Results show that both drugs are effective in promoting some weight loss. Nearly 82% of patients taking Mounjaro lost 5% or more of their body weight, compared to nearly 67% of those taking Ozempic, researchers found.

However, Mounjaro users were more likely to achieve greater weight gain. About 42% of Mounjaro patients lost 15% or more of their body weight, compared to about 18% of those taking Ozempic.

Overall, patients on Mounjaro were 76% more likely than those on Ozempic to lose 5% or more of their body weight; 2.5 times more likely to lose 10% or more of their body weight; and 3.2 times more likely to lose 15% or more of their body weight, results show.

Mounjaro patients also experienced larger reductions in body weight throughout their first year on the drug, researchers added.

After three months, Mounjaro patients had lost about 6% of their body weight compared to under 4% for Ozempic patients. The difference was 10% versus 6% at six months, and 15% to 8% at one year.

Both drugs work by mimicking the effects of the gut hormone GLP-1, which plays a role in maintaining stable blood sugar levels. This action also slows digestion and increases satiety.

However, Mounjaro also stimulates a second gut hormone called GIP, which might explain the boosted effects found in this study.

More information

Rush University has more about weight-loss drugs.

SOURCE: JAMA Internal Medicine, news release, July 8, 2024