Novo Nordisk, the Danish manufacturer of Ozempic, has launched a lawsuit against US rival Eli Lilly over what it describes as “false and materially misleading” adverts for its weight-loss and anti-diabetes treatments Zepbound and Mounjaro.
The complaint alleges that Eli Lilly “intentionally selected outdated studies” that compared the highest doses of its own drugs against lower doses of Novo Nordisk’s medicines, and “deceptively presented those results as proof of broad, product-level superiority while burying or omitting critical clinical context”.
“As new and more effective treatment options become available, people deserve accurate information that reflects the latest scientific evidence and helps them make informed care decisions,” said John F Kuckelman, Novo Nordisk’s general counsel. He added that “ineffective, fine-print disclaimers do not fix the misleading impression created by major national campaigns”.
Eli Lilly responded by stating that the trial underpinning its advertising, Surmount-5, is “the only direct, head-to-head randomised clinical trial comparing tirzepatide and semaglutide in the context of weight management”. A spokesperson said: “Rather than competing on the merits of its products, Novo is asking a court to prevent Lilly from communicating the results of this trial. We firmly stand by our advertising campaign.”
Novo Nordisk’s drugs use the molecule semaglutide, while Eli Lilly’s treatments use tirzepatide. Both belong to a class of anti-obesity medicines that mimic the hormone GLP-1, used for weight loss and treating type 2 diabetes.
