Wegovy cuts heart risk by 57% vs. Lilly in weight-loss study

Novo Nordisk said on Sunday its blockbuster weight-loss drug Wegovy cut the risk of heart attack, stroke or death by 57% versus Eli Lilly’s rival medicines Mounjaro and Zepbound in a real-world comparison of overweight and obese patients with cardiovascular disease but not diabetes.

While this was not a randomized controlled trial, Novo said the findings provide evidence that the heart-protective benefits of Wegovy and its main ingredient semaglutide may not be the same for all GLP-1 drugs, such as tirzepatide, the active ingredient in Zepbound and Mounjaro.

Compared with tirzepatide, a 2.4 milligram dose of Wegovy showed a significant 57% greater risk reduction for heart attack, stroke and cardiovascular-related death or death from any cause while on treatment with no gaps of more than 30 days, the Danish drugmaker said.

The actual number of major adverse heart events was low for both drugs – 15, or 0.1%, of patients on Wegovy and 39, or 0.4%, of tirzepatide patients. The average follow-up duration was 3.8 months for the Wegovy group and 4.3 months for tirzepatide.

The data, gathered from more than 21,000 patients and presented at the European Society of Cardiology meeting in Madrid, also showed a 29% reduction in heart risk and death from any cause in Wegovy users compared with tirzepatide users regardless of any gaps in their treatment.

The findings could provide a boost for Novo, which has been losing U.S. market share to Zepbound since becoming Europe’s most valuable company last year on booming sales of Wegovy.

Earlier in August, Novo implemented a global hiring freeze for non-critical job roles, highlighting the increased competition in the industry, which also led to Denmark slashing its 2025 economic growth forecast, anticipating dampened growth expectations for the pharmaceutical giant.

Zepbound and Wegovy currently dominate the weight-loss market, which some analysts expect to reach $150 billion by the early 2030s.

The U.S. Food and Drug Administration is reviewing a high-dose oral version of Wegovy for potential approval later this year. Novo said it helped overweight or obese adults lose 15% of their weight in a late-stage trial.

Real-world studies cannot prove cause and effect the way randomized clinical trials do. Other limitations of the study include the short follow-up duration.