New Delhi, July 21 -- Novo Nordisk said on Tuesday it was suing rival Eli Lilly in U.S. federal court, accusing the U.S. drugmaker of false advertising for claiming its weight-loss medicines outperform Novo's.

The Danish company said it filed the lawsuit in U.S. District Court in New Jersey, alleging that Lilly violated federal and state false advertising and unfair competition laws, including the Lanham Act, through nationwide advertising campaigns for the obesity drug Zepbound and the diabetes treatment Mounjaro.

Novo alleges Lilly compared the highest approved doses of its medicines with lower doses of Novo's Wegovy and Ozempic while omitting newer, higher-dose versions that Novo says deliver greater weight loss.

Novo said it is see...