Novo Nordisk sues Eli Lilly over alleged false advertising of weight‑loss drugs

Novo Nordisk filed a lawsuit in the U.S. District Court for the District of New Jersey, accusing Eli Lilly of misleading U.S. consumers with advertisements for its obesity drugs Zepbound and Mounjaro. The complaint says Lilly’s ads compare the highest approved doses of its medicines with lower‑dose versions of Novo’s Wegovy and Ozempic, omitting the newer 7.2 mg dose of Wegovy approved in March 2026. Novo claims the ads have been shown more than 700 million times and present “false and deceptive” information that could influence consumer perception.

Novo seeks a permanent injunction ordering Lilly to cease the campaigns, to run corrective advertising, and to pay damages for the alleged unfair competition. The case follows a cease‑and‑desist letter sent by Novo in April after Wegovy’s higher dose was approved. Both companies are competing for dominance in the global GLP‑1 market, projected to exceed $100 billion by 2030, with Novo’s Wegovy and Lilly’s Zepbound leading in sales.

The lawsuit highlights the broader battle over marketing practices in the rapidly growing obesity‑treatment sector, where each firm is investing heavily in advertising, new formulations, and partnerships to capture market share.