Novo Nordisk sues Eli Lilly to block rival weight-loss adverts

Novo Nordisk has launched a legal attack against Eli Lilly, demanding the immediate withdrawal of advertising campaigns for its rival weight-loss medicine. The Danish pharmaceutical company accuses its American competitor of manipulating clinical data to falsely claim superiority over Wegovy.

The core of the complaint centres on how the rival drug's efficacy was presented to American patients. According to Novo Nordisk, Eli Lilly compared the highest dose of its own medicine to the lowest dose of Wegovy. Furthermore, the advertisements relied on outdated studies and ignored the fact that American health authorities approved a higher 7.2 milligram dose of Wegovy in March.

These adverts have been prominently placed during sports broadcasts and promoted heavily on Facebook and TikTok. Novo Nordisk’s chief legal officer, John F. Kuckelman, stated that viewers are left with the inaccurate impression that the competitor’s products are far more effective. For European investors, this dispute highlights how fiercely the battle for the weight-loss drug market is now being fought through aggressive consumer marketing.

Novo Nordisk has issued a strict 48-hour ultimatum for Eli Lilly to pull the adverts from all platforms. The Danish company is also demanding that Eli Lilly launch a new campaign to actively correct the alleged misinformation. If Eli Lilly fails to comply with these demands, Novo Nordisk intends to seek a formal injunction against the advertisements.

“At the same time as we filed the lawsuit, we also sent a letter to Lilly asking them - regardless of the lawsuit - to stop running the advertisements,” Kuckelman said. This rapid escalation to the courts demonstrates the severe commercial threat that Novo Nordisk perceives in these advertising campaigns.

As a dominant European player in the obesity sector, Novo Nordisk's future earnings rely heavily on defending its market position in the United States. When competitors use selective clinical data in mass-market social media and television campaigns, it has the potential to directly shift patient demand and doctor prescribing habits.

Eli Lilly has firmly rejected the allegation that its marketing is misleading, criticising Novo Nordisk’s decision to pursue litigation. “We stand behind our adverts. We will continue to focus on science and defend ourselves resolutely against Novo Nordisk’s lawsuit,” the company told Reuters. “It is truthful, it is transparent, and it is based on the most direct scientific evidence available,” they added.