Whether a GLP-1 medication is approved for diabetes or chronic weight management, declaring one therapy as "best" for weight loss is tricky.
Trials that test these drugs for weight loss results are not uniform, with studies lasting anywhere from 13 to 72 weeks. Add in weak medication adherence and varying results for different Body Mass Index classes, and the equation becomes more muddled.
Researchers recently compared Mounjaro and Ozempic, which are both approved for Type 2 diabetes, to see which led to greater weight loss. In their review of more than 18,000 patient records, Mounjaro surpassed Ozempic at three, six and 12 months for larger reductions in body weight.
Diana Thiara, MD, medical director of UCSF Health's weight loss program in San Francisco, and Susan Z. Yanovski, MD, co-director of the Office of Obesity Research at the National Institute of Diabetes and Digestive and Kidney Diseases, told The New York Times current data does not point to a first-line therapy.
Dr. Thiara said the only available information stems from "highly flawed studies," including the Mounjaro-versus-Ozempic research. EHR data does not specify why the patients are taking the medications, Dr. Yanovski said, and many of the patients had off-label prescriptions. By the end of the trial, less than half of patients continued their regimen.
The researchers noted when a prescription was filled, but it is unknown what the doses were, which adds another murky level since different doses can lead to different weight loss results, lead researcher Tricia Rodriguez, PhD, told the Times.
Future trials might yield clearer results, the Times reported July 19. Eli Lilly is currently testing its weight loss medication Zepbound against Wegovy, Novo Nordisk's weight loss drug, in people with obesity who do not have diabetes. The study is expected to end later this year.