Novo Nordisk Loses US Ruling Over Eli Lilly Obesity Drug Ads

Novo Chief Executive Officer Mike Doustdar's strategy for clawing back market share includes litigation against competitors. In the July 21 lawsuit, Novo said Lilly's ad campaigns for GLP-1 medicines were "maliciously and deliberately false."

According to the Novo complaint, Lilly ads say people on Zepbound lost an average of 50 pounds, while Wegovy users lost an average of 33 pounds. Those ads relied on a study published in 2025 in which Zepbound beat Wegovy in a head-to-head trial. But Novo later got approval for a higher dose of its drug than that study used.

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A better comparison, Novo argued, was either of two different studies. In one, Novo's high-dose Wegovy showed average weight loss of 47 pounds. In another, Zepbound helped people lose an average of 48 pounds. The Food and Drug Administration approved the more intense Wegovy shot - which uses triple the previous highest dose - in March, and Novo started marketing it in April. Novo claims it's too soon to share data on how many patients are taking the new triple dose.

Lilly's Retort

In court filings and a two-day hearing in late August, Lilly's lawyers urged Quraishi to reject Novo's request for a preliminary injunction and its demand for corrective advertising.

"Lilly is beating Novo in the marketplace, and the reason is that Lilly's medicines are more effective in treating diabetes and obesity," company lawyers wrote in an Aug. 10 filing. "Lilly ran head-to-head clinical studies to show as much. Instead of advancing the science or running head-to-head studies of its own, Novo tries to compensate for its shortcomings with this lawsuit."

A lawyer for Lilly, Gregg LoCascio, argued at an Aug. 28 hearing that the company's ads were accurate and factual, and they don't amount to false advertising. He argued that Novo had failed to show that it would succeed in the lawsuit or that the ads caused irreparable harm to the company.

"This case is clear," LoCascio said. "Lilly's science is unassailable. Lilly's advertisements are truthful. Novo has not proven any entitlement, success on the merits, irreparable injury."

Novo is seeking to recover the profits it lost through the advertising, as well as triple that amount under US law. The lawsuit alleges Lilly violated US and state false advertising and unfair competition laws, including the federal Lanham Act.

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The case is Novo Nordisk v. Eli Lilly, 26-cv-9027, US District Court, District of New Jersey (Trenton).