Novo Nordisk has sued Eli Lilly in a US federal court, accusing the company of false advertising related to its weight-loss medicines.
Novo claims Lilly compared the highest doses of its drugs with lower doses of Novo's medicines while leaving out newer, higher-dose versions.
The company is seeking damages and a court order requiring Lilly to withdraw the advertisements and issue corrective ads.
Novo Nordisk has filed a lawsuit against rival Eli Lilly in a US federal court, accusing the American drugmaker of misleading consumers by claiming its weight-loss medicines outperform Novo's treatments, according to a Reuters report.
The lawsuit was filed in the US District Court in New Jersey and alleges that Lilly violated federal and state laws governing false advertising and unfair competition through nationwide promotional campaigns for its obesity drug Zepbound and diabetes medicine Mounjaro.
4 July 2026
Get the latest issue of Outlook Business
Novo Nordisk is seeking damages as well as a court order requiring Lilly to withdraw the advertisements and launch a corrective advertising campaign.
Novo Challenges Comparisons in Lilly's Ads
According to the report, Novo Nordisk alleges that Lilly's advertisements compare the highest approved doses of Zepbound and Mounjaro with lower doses of Novo's Wegovy and Ozempic, while excluding newer, higher-dose versions of its medicines.
In its complaint, Novo argued that the advertisements rely on outdated clinical trial data and present an unfair comparison of the medicines' weight-loss results.
The Danish drugmaker said it had asked Lilly to stop the campaign after the US approved a 7.2-milligram dose of Wegovy in April. However, Novo said Lilly did not respond to its cease-and-desist letter and instead added what Novo considers an inadequate disclaimer to the advertisements.
Advertisement
Company Seeks Damages, Corrective Campaign
Novo said it plans to seek a preliminary injunction if Lilly does not voluntarily remove the advertisements. It is also seeking damages, including profits that it claims Lilly earned as a result of the advertising campaign.
According to the news agency, Novo said Lilly's campaign has reached consumers more than 700 million times since the advertisements were modified after the April letter.
Novo's General Counsel John Kuckelman told Reuters that Lilly's advertisements compare weight-loss results of about 50 pounds for Zepbound with around 33 pounds for Wegovy. He said no head-to-head trial has compared the highest approved doses of the medicines. According to Reuters, separate late-stage trials showed average weight loss of about 48 pounds for Zepbound and 47 pounds for Wegovy.
