Mounjaro® vs Wegovy® For Weight Loss

How Effective is Mounjaro® vs Wegovy®

Both Wegovy® and Mounjaro® are very effective at lowering body weight along with diet and exercise. The effectiveness of these medications is demonstrated in the following major studies:

The SURMOUNT-1 trial published in 2022 was a large phase 3 clinical trial with over 2500 participants that looked at how effective tirzepatide (the primary active ingredient in Mounjaro®) was at managing obesity. (1) Tirzepatide was given at different doses for a period of 72 weeks to groups of non-diabetic participants who were struggling with weight gain. The participants were also enrolled in a calorie-restricted diet, expected to engage in 150 minutes of exercise per week, and were regularly scheduled to meet with a dietician. 

‍They found that after 72 weeks, those taking tirzepatide experienced 15-21% weight loss, which was significantly more than the 3% weight loss experienced by those in the placebo group. This showed us that the use of Mounjaro® in combination with diet and exercise is very effective at treating obesity. 

‍The STEP 1 Trial was another large randomized control trial with around 1900 participants that examined how effective semaglutide (the primary active ingredient in Wegovy®) was at treating obesity in non-diabetic patients (2). Semaglutide was given as a once-weekly pen injection over a period of 68 weeks. Like the SURMOUNT trial, all participants also underwent a calorie-restricted diet, exercised for 150 minutes per week, and met regularly with dieticians. 

They found that participants taking semaglutide experienced an average of 14.9% weight loss compared to only 2.4% in the placebo group. The study also reported increased participant-reported physical function after the study, which was not measured in the SURMOUNT trial.‍

The mean change in body weight across both studies was about the same (~15%); however, more participants achieved at least a 5% reduction in body weight when taking Mounjaro® compared to Wegovy® based on the data reported in the two trials. Ultimately, both were very effective at managing weight loss in combination with diet and exercise.