As the use of weight-loss medications grows among doctors and patients, researchers are focused on determining the effectiveness and side effects of these drugs to tailor treatments to individual needs. A recent study published in the New England Journal of Medicine and presented at the European Congress on Obesity sheds light on two prominent medications: Wegovy (semaglutide) from Novo Nordisk and Zepbound (tirzepatide) from Eli Lilly.
In a head-to-head trial involving 751 participants, those administered Zepbound experienced a greater average weight loss of 20.2% over 15 months compared to 13.7% in the Wegovy group. Additionally, waist circumference reductions were more significant in the Zepbound group, with a loss of 18.4 cm versus 13.0 cm for Wegovy.
Both medications reported similar side effects, primarily gastrointestinal symptoms like nausea and diarrhea, although Zepbound users noted more injection-site reactions, which diminished over time. Experts emphasize that weight loss is not the sole metric for evaluating these drugs, as obesity often correlates with various health issues, including heart, kidney, and liver conditions.
Wegovy has received FDA approval for reducing cardiovascular risks in overweight individuals with a history of heart problems, a distinction not currently held by Zepbound. However, studies indicate both medications may lower the risk of heart failure and improve liver and kidney health in certain patients. Zepbound is also approved for reducing obstructive sleep apnea risk in obese patients.
The findings aim to aid physicians in making informed decisions regarding which drug may best suit individual patients. Future studies will explore long-term effects and the potential for oral versions of these treatments, which could broaden access and support ongoing weight management strategies.