In a recent study conducted in the real world, overweight and obese adults taking the injected medication Mounjaro demonstrated more significant weight loss results compared to their counterparts using a similar medication, Ozempic.
These findings have raised interest in the potential of these drugs to not only treat type 2 diabetes but also aid in substantial weight loss.
Both Ozempic, known as semaglutide, and Mounjaro, referred to as tirzepatide, work by mimicking the effects of the gut hormone GLP-1. This hormone plays a crucial role in stimulating the production of insulin, slowing down the passage of food through the stomach, and signaling the brain to control appetite. Additionally, tirzepatide activates another gut hormone called GIP, which may further enhance its effectiveness in weight management.
It’s essential to note that while this study provides valuable insights, it has not undergone peer-review and publication in a professional journal. However, its results align with previous observations from clinical trials, suggesting the potential efficacy of tirzepatide in promoting weight loss.
With over 70% of American adults struggling with overweight or obesity, there is significant interest in medications like Mounjaro and Ozempic as potential solutions.
However, there remains a lack of comprehensive information regarding their comparative effectiveness, especially in individuals without diabetes. Although a head-to-head study is currently underway, results are not expected for over a year.
The study was independently initiated by Truveta, a data analytics company owned by 30 US healthcare systems. Truveta combines anonymous patient records from these hospitals to address various research questions, including medication effectiveness.
Comparing Weight Loss Medications
The US Food and Drug Administration (FDA) has approved higher doses of both tirzepatide and semaglutide for weight loss, under the names Zepbound and Wegovy, respectively. However, this study focused solely on the doses approved for type 2 diabetes treatment, which may limit the scope of its conclusions. The study analyzed patient records spanning from May 2022 to September 2023.
Dr. Patricia Rodriguez, the lead author of the study and a senior applied scientist at Truveta Research, and her team sifted through thousands of patient records to identify overweight and obese adults using either Mounjaro or Ozempic.
Among the 18,000+ participants in the study, approximately 52% had type 2 diabetes, while the remaining 48% had no documented diabetes history in their medical records. This suggests that a substantial portion of the participants was likely using these medications off-label for weight loss. It’s worth noting that many participants discontinued the medications during the study period, possibly due to medication shortages.
Common side effects reported in the medical records included nausea and vomiting in about 1 in 5 patients and gallstones in roughly 1 in 6 patients. Notably, the study found no significant differences in side effect rates between the two medications.
Weight Loss Results
Individuals without diabetes who took Mounjaro experienced more significant weight loss compared to those using Ozempic. After three months, Mounjaro users achieved an average weight loss of approximately 6%, while Ozempic users saw nearly 4% weight loss.
At six months, Mounjaro users maintained a 10% average weight loss, while Ozempic users achieved 6%. At the one-year mark, people on Mounjaro had lost an average of 15% of their body weight, compared to about 8% for those on Ozempic. After adjusting for potential sources of bias, these differences narrowed.
The Best Choice for Weight Loss
Dr. Mopelola Adeyemo, a specialist in diabetes and obesity at the University of California, Los Angeles, emphasizes that the most suitable weight loss medication varies from person to person. Some patients may not tolerate one form of GLP-1 medication like Ozempic or Mounjaro but may find success with a different one. She suggests that both medications have demonstrated effectiveness not only in weight loss but also in managing diabetes and providing other cardiovascular benefits.
However, Novo Nordisk, the manufacturer of Ozempic and Wegovy, argues that the study does not provide a fair comparison. They highlight that the doses of semaglutide evaluated in the analysis have not been studied for chronic weight management. Additionally, there are no head-to-head trials comparing Wegovy and tirzepatide at the dosages used for weight loss.
Eli Lilly, the company behind Mounjaro and Zepbound, discourages the off-label use of its medication and urges patience as they work to gather more information. They mention their SURMOUNT-5 trial, which will compare tirzepatide (Zepbound) and semaglutide (Wegovy) for obesity treatment, with results expected in 2025.
The study suggests that Mounjaro may offer a more potent solution for weight loss compared to Ozempic, particularly in individuals without diabetes. However, the choice of the most suitable medication should be based on individual tolerance and effectiveness. Patients should consult their healthcare providers to determine the best option for their specific needs.