Thursday, July 23, 2026

Novo Nordisk sues Eli Lilly over GLP-1 advertising

Novo Nordisk has filed a lawsuit in the United States against Eli Lilly and Company and Lilly USA. The case, brought in the United States District Court for the District of New Jersey, challenges national direct-to-consumer campaigns for Zepbound and Mounjaro.

According to Novo Nordisk, the complaint alleges violations of federal and state rules on false advertising and unfair competition, including the Lanham Act. The company argues that Lilly’s comparative advertising uses selected clinical data in a way that may give patients an incomplete view of GLP-1 treatment options for obesity and type 2 diabetes.

Dispute over comparative claims

The lawsuit focuses on campaigns that, according to Novo Nordisk, compare high doses of Lilly medicines with lower doses of Novo Nordisk products. For Zepbound, Novo Nordisk says the advertising refers to comparisons with Wegovy 1.7 mg or 2.4 mg, while not reflecting the injectable Wegovy 7.2 mg dose approved by the FDA in March 2026.

Novo Nordisk points to the STEP UP trial, in which Wegovy 7.2 mg showed mean weight loss of 18.8 percent at 72 weeks. The company says this corresponds to about 47 pounds. Novo Nordisk also states that no head-to-head clinical trial has compared the highest approved doses of Zepbound and Wegovy.

The complaint also covers Mounjaro advertising. Novo Nordisk says Lilly compares Mounjaro 15 mg with Ozempic 1 mg, although a higher 2 mg maintenance dose of Ozempic has been FDA-approved for more than four years.

Remedies sought

Novo Nordisk says Lilly did not withdraw or sufficiently amend certain advertisements after a formal cease-and-desist request. The company is seeking a permanent injunction to stop the challenged comparative advertising across platforms and to require corrective advertising.

Novo Nordisk also says it plans to seek a preliminary injunction if Lilly does not voluntarily remove the ads. The company says it has evidence that consumers are being confused or misled by the campaigns.

According to Novo Nordisk, the challenged consumer campaigns have appeared around major global sports broadcasts and on TikTok and Facebook.

Market context

The case highlights the commercial and communications stakes in the US GLP-1 market. Comparative advertising in this field remains particularly sensitive as approvals, dosing options and clinical evidence continue to evolve.