Dec. 4, 2024 – People taking the weight loss drug Zepbound experienced dramatically greater weight loss than competitor Wegovy in the first head-to-head trial.
Those who took Zepbound lost on average of 50 pounds, compared to 33 pounds lost among those who took Wegovy. That’s the equivalent of losing 20% of body weight with Zepbound, versus nearly 14% with Wegovy.
Participants were randomly assigned to take one of the drugs for 72 weeks. All of the 751 people did not have diabetes, but they had either obesity or were overweight plus had one other health condition such as high blood pressure or high cholesterol.
For both drugs, the majority of people lost less than 25% of their body weight. Nearly 32% of people taking Zepbound lost less than 25% of their body weight, and 16% of people lost less than one-quarter of their body weight with Wegovy.
The active ingredient in Zepbound is called tirzepatide, which is the same active ingredient in the diabetes drug Mounjaro. Wegovy and its diabetes counterpart Ozempic contain the active ingredient semaglutide.
The study was funded by Zepbound-maker Eli Lilly, which released the results via a press release on its website for investors. Pharmaceutical companies are subject to regulations regarding disclosures that could affect investment decisions.
The results have not yet been published in a peer-reviewed medical journal, and the initial information published by Eli Lilly was limited.
The findings are not unexpected. Other analyses have suggested that Zepbound may lead to greater weight loss than competitors, but those findings were not made using the rigorous scientific process of a clinical trial such as the one Eli Lilly used. The company said full results will be published in a peer-reviewed journal and presented at a medical conference next year.
