A new phase 3 clinical trial found that Eli Lilly's weight loss drug Zepbound resulted in significantly greater weight loss than Wegovy.
Over a 72-week period, patients taking Zepbound lost an average of 20.2% of their body weight, compared to 13.7% for those taking Wegovy, according to a Dec. 4 Eli Lilly news release.
The trial studied adults who were either obese or overweight and had at least one weight-related health issue, excluding diabetes. Zepbound outperformed Wegovy on both the primary endpoint and all five secondary endpoints. Notably, 31.6% of Zepbound users achieved 25% weight loss, with only 16.1% of those using Wegovy reaching that milestone.
Both drugs belong to a class of GLP-1 receptor agonists, which reduce appetite by mimicking hormones that regulate food intake. However, Zepbound also targets a second hormone, GIP, which may help improve how the body processes sugar and fat, NBC News reported Dec. 4. Susan Pratt, MD, an endocrinologist at Duke Health told the outlet that while Zepbound led to greater weight loss, both drugs are highly effective in treating obesity.
Previous research had indicated that Zepbound was more effective than Wegovy, but those studies relied on retrospective data and not true comparative trials, according to the NBC News report.
The safety profiles of both drugs were similar, with the most common side effects being mild to moderate gastrointestinal issues.