Novo Nordisk sues US rival Eli Lilly over 'materially misleading' weight-loss ads

Novo Nordisk announced on Tuesday that it is suing its arch US rival Eli Lilly over 'false and materially misleading' adverts for its competing weight-loss and anti-diabetes treatments. The Danish pharmaceutical heavyweight complained that the US group – which makes rival weight-loss treatments Zepbound and Mounjaro – 'intentionally selected outdated studies' that compared Lilly’s highest doses against lower doses of Novo Nordisk’s medicines.

Eli Lilly’s ads 'deceptively presented those results as proof of broad, product-level superiority while burying or omitting critical clinical context', Novo Nordisk said. Novo Nordisk has developed a molecule called semaglutide, while Eli Lilly developed rival molecule tirzepatide.

'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.

The target of the Danish group’s wrath is an advertising campaign that was 'aired during recent, widely viewed global sporting broadcasts and on TikTok and Facebook, causing widespread confusion', it said.

Eli Lilly responded to its rival’s accusations with a statement saying that the trial which underpins its advertising, known as Surmount-5, is 'the only direct, head-to-head randomised clinical trial comparing tirzepatide and semaglutide in the context of weight management'. An Eli Lilly spokesperson added that 'rather than competing on the merits of its products, Novo is asking a court to prevent Lilly from communicating the results of this trial'.

Anti-obesity treatments mimic a hormone secreted by the intestines, GLP-1, and can be used for weight loss and/or to treat type 2 diabetes.