November 28, 2023: A recent comparative analysis of Eli Lilly and Novo Nordisk’s weight loss drugs on diabetes patients showed Eli Lilly’s drug Zepbound, powered by Tirzepatide, surpassing Novo Nordisk’s Wegovy, based on Semaglutide, in promoting weight loss.
The study conducted by health data company Truveta, focused on over 40,000 overweight or obese patients with Type 2 diabetes. Results from this real-world analysis revealed that patients prescribed Tirzepatide (Mounjaro) were notably more likely to achieve weight loss milestones of 5%, 10%, and 15% compared to those on Semaglutide (Ozempic).
The research considered patients who had not received either drug before May 2022. It utilized electronic health records data from US healthcare systems collected by Truveta, including both diabetic and non-diabetic patients. Zepbound recipients experienced an average weight loss of 15.2% after 12 months, outperforming Wegovy recipients who achieved a 7.9% weight reduction over the same period.
Comparison of Zepbound and Wegovy
Patients on Zepbound consistently demonstrated better weight loss outcomes at three, six, and 12 months compared to those on Wegovy. The study found that 81.8% of Tirzepatide recipients lost more than 5% of their weight within a year, while only 64.6% of Semaglutide recipients achieved the same result.
The study hinted at the potential factors contributing to Zepbound’s superior efficacy, pointing to the dual action of Tirzepatide on both GLP-1 and GIP receptors, compared to Ozempic’s activation of only the GLP-1 receptor. This dual mechanism may be the key to Zepbound’s enhanced weight loss outcomes.
While awaiting the results of an ongoing head-to-head trial comparing Zepbound and Wegovy, the study adds weight to the argument favoring Eli Lilly’s drug. The head-to-head trial, expected in 2025, aims to provide more definitive insights into the relative effectiveness of the two medications.
Lilly said in a statement that it had not sponsored the study. The company also said that it does not “promote or encourage the off-label use” of its medicines.
Novo noted that the study analyzed the weight effects of Ozempic, which is not approved for weight loss, and not its drug Wegovy. “The doses of semaglutide evaluated in this analysis have not been investigated for chronic weight management, and there are no head-to-head trials that have reported which evaluate Wegovy and tirzepatide,” Novo said.
As both Eli Lilly and Novo Nordisk navigate the evolving weight loss drug market, ongoing research and real-world evidence will continue to influence the trajectory of these medications.
The study can be accessed here.