Mounjaro beats Ozempic for weight loss in early trial

The diabetes drug Mounjaro prompted more weight loss among overweight and obese adults than Ozempic did in a real-world setting, researchers report.

Both Mounjaro (tirzepatide) and Ozempic (semaglutide) mimic the effects of the gut hormone GLP-1, which triggers insulin production, helps control appetite and slows the movement of food through the stomach. But Mounjaro also stimulates a second gut hormone known as GIP, which may explain the findings, the investigators said.

Both medications treat type 2 diabetes, but they have become wildly popular because they also help people shed unwanted pounds.

Because of that, the U.S. Food and Drug Administration has approved higher doses of both Mounjaro and Ozempic for weight loss under the brand names Zepbound and Wegovy, respectively.

The new study was published recently on the preprint server MedRxiv and hasn't yet undergone peer-review so should be considered preliminary.

Many doctors have suspected Moinjaro might be more potent after seeing how their diabetes patients fared on both drugs, CNN reported. However, there haven't been many studies that compared the drugs head-to-head, especially in people who don't have diabetes.

"Over 70% of American adults have overweight or obesity, and so there's this huge potential for these medications to be used and [there's] really a lack of information," lead study author Dr. Patricia Rodriguez, a senior applied scientist at Truveta Research, told CNN.

The study was conducted by Truveta, a data analytics company owned and operated by 30 US health care systems. It looked only at the lower doses, which are used to treat type 2 diabetes.

Rodriguez and her team combed through thousands of patient records to find overweight and obese adults on Mounjaro or Ozempic. Of more than 18,000 people included in the study, 52% had type 2 diabetes. The other 48% had no history of diabetes, so researchers believe patients in this group were probably prescribed the medications off-label for weight loss.

Patients lost more weight the longer they stayed on either medication. Still, nearly half of people in the study stopped taking the drugs during the study period, which ran from May 2022 to September 2023.

While it's hard to say why so many quit the medications, both Mounjaro and Ozempic have been in short supply, the researchers noted. The most common side effects reported were nausea and vomiting, affecting about 1 in 5 patients. Meanwhile, gallstones were reported for roughly 1 in 6 patients.

People lost more weight on the medications if they didn't have diabetes, but those taking Mounjaro lost a greater percentage of their starting weight than those taking Ozempic, the study found.

The average weight loss was about 6% for Mounjaro users at three months, compared with nearly 4% for those on Ozempic. After six months, the average weight loss with Mounjaro was 10%, compared with 6% for Ozempic. At 12 months, people had dropped an average 15% of their body weight on Mounjaro, compared with about 8% on Ozempic.

Ozempic's maker Novo Nordisk took issue with the new study.

"The doses of semaglutide evaluated in this analysis have not been investigated for chronic weight management, and there are no head-to-head trials that have reported which evaluate Wegovy and tirzepatide," a company spokesperson said in a statement.

The company pointed out that semaglutide is used at a higher dose when weight loss is the goal.

The findings largely mirror results posted from earlier clinical trials, so they aren't surprising, Dr. Mopelola Adeyemo, who treats people with diabetes and obesity at the University of California, Los Angeles, told CNN.

But he added that he sees room for both company's drugs in the future.

"I think there's going to be roles for both of them, definitely, because both have been shown to not only help with weight loss but also diabetes and another cardiovascular benefits, as well," Adeyemo said.

Copyright © 2023 HealthDay. All rights reserved.