Novo Nordisk Reportedly Escalates Legal Battle Against Eli Lilly – Even As Analysts See LLY Leading The GLP-1 Race

Novo Nordisk is seeking a preliminary U.S. court injunction to immediately block Lilly’s advertisements for Zepbound and Mounjaro, according to a Reuters report on Friday.

• Novo is also seeking a permanent injunction requiring Lilly to withdraw the campaigns and publish corrective advertisements
• The development follows a lawsuit Novo filed earlier this week in the U.S. District Court for the District of New Jersey, alleging that Lilly violated federal and state false advertising and unfair competition laws.
• MorningStar estimates the global GLP-1 market could reach $200 billion by 2035, with Lilly expected to capture around $120 billion of that market.

Novo Nordisk (NVO) is escalating its legal battle with Eli Lilly (LLY), seeking a preliminary U.S. court injunction to immediately block Lilly’s advertisements for blockbuster diabetes and weight-loss drugs, Zepbound and Mounjaro.

“Novo Nordisk is seeking a court order on ‌an ⁠expedited basis to ensure people can access the accurate, complete picture of the treatments available to them today,” Novo said, as reported by Reuters.

Novo Challenges Comparisons in Lilly’s Ad Campaigns

The latest development follows a lawsuit Novo Nordisk filed earlier this week in the U.S. District Court for the District of New Jersey. The company alleged that Lilly violated federal and state false advertising and unfair competition laws through nationwide marketing campaigns.

According to Novo, Lilly’s Zepbound advertisements compare the drug’s highest approved dose with lower doses of Wegovy while excluding Wegovy's newer 7.2 mg dose, which received U.S. Food and Drug Administration (FDA) approval in March 2026.

Novo argued that no head-to-head clinical trial has compared the highest doses of the two obesity drugs, making the advertisements misleading.

The company raised similar concerns about Lilly’s Mounjaro campaign, alleging that it compares the highest 15 mg dose of Mounjaro with only the 1 mg dose of Ozempic instead of its FDA-approved 2 mg maintenance dose.

According to the Reuters report, Eli Lilly denied the allegations on Tuesday and said it stands by its advertising, adding that it intends to vigorously defend itself. The company did not immediately respond to Reuters’ requests for additional comment on Friday.

Wall Street Says LLY To Be The Dominant Player In GLP-1 Market

Separately, Wall Street remains optimistic about Lilly’s long-term outlook. Earlier this week, MorningStar analysts highlighted Lilly’s heavy investment in research and development, strong pipeline, and leadership in the fast-growing GLP-1 market. Mounjaro and Zepbound accounted for more than half of Lilly's sales in 2025, while its recently launched oral obesity treatment, Foundayo, is expected to further strengthen its position, the report read.

MorningStar estimates the global GLP-1 market could reach $200 billion by 2035, with Lilly expected to capture around $120 billion of that market.

Retail's Take On LLY, NVO

While retail sentiment on Stocktwits surrounding both NVO and LLY trended in the ‘bearish’ territory over the past 24 hours.

On a year-to-date basis, LLY has gained 9.8%, while NVO has declined about 8%.

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