Novo Nordisk CEO defends Lilly lawsuit over weight-loss drug ads and acknowledges Lilly's lead

Novo Nordisk CEO Mike Doustdar on Aug. 12 defended his company's lawsuit against Eli Lilly over advertising for competing weight-loss drugs, telling CNBC that "competition has to be fierce, but I also think competition has to be fair" ^[1]. In the same interview he acknowledged that Lilly has pulled ahead in injectable GLP-1s, while pointing to more than 5 million U.S. prescriptions for Novo's new Wegovy pill ^[1].

Novo filed the suit in July 2026, alleging that Lilly's advertising for its injectable GLP-1 drugs misleads consumers about how well they work compared with Novo's treatments ^[1]. Lilly said at the time that it stands "firmly behind our advertising" ^[1].

The ads cite a head-to-head trial of Lilly's Zepbound (tirzepatide) against Novo's Wegovy (semaglutide). Published in the New England Journal of Medicine in May 2025, the trial found that the maximum tolerated dose of 10 mg or 15 mg of Zepbound over 72 weeks produced average weight loss of 20.2%, or about 50 pounds, compared with 13.7%, or roughly 33 pounds, for the then-maximum tolerated dose of 1.7 mg or 2.4 mg of Wegovy ^[1].

Doustdar's argument is that those comparisons rely on an older, lower-dose Wegovy rather than a higher-dose 7.2 mg version that the Food and Drug Administration approved in March 2026 ^[1]. Novo says its own study of 7.2 mg Wegovy showed average weight loss of about 19%, or 47 pounds, over 72 weeks — much closer to the top-dose Zepbound result from the earlier trial ^[1]. "We believe that the advertisements that they have been doing, while truthful, is not the complete picture," Doustdar said, adding that the ads are "built on older generations of these products and old doses" ^[1].

Lilly pushed back in a statement, saying it was glad Novo's own CEO had confirmed that Lilly's advertising is truthful ^[1]. Lilly also said the suggestion that higher-dose Wegovy is on par with Zepbound "isn't supported by any head-to-head clinical trial," and that Zepbound is the most prescribed obesity medicine in the U.S. ^[1].

The dispute comes as the two companies compete across a fast-growing market. Since the suit was filed, Novo shares have fallen 6% while Lilly shares have climbed nearly 4% ^[1]. Doustdar conceded the injectable picture: "There is no secret that Lilly has been quite successful, actually, in having volume uptake and market share uptake above and beyond Novo," he said ^[1].

Each company now also sells an oral option. The Wegovy pill launched in early January 2026 after FDA approval in late December 2025, and Doustdar said U.S. prescriptions have passed 5 million, calling it the "best product launch in the history of pharmaceuticals" ^[1]. Lilly's weight-loss pill, Foundayo (orforglipron), was approved on April 1, 2026, and began shipping days later; it missed expectations in Lilly's latest earnings report as the company works to build consumer awareness ^[1].

Why it matters for patients

The lawsuit is about advertising claims, not about whether any of these drugs is approved or available. Both companies cite real trial results, but the numbers come from different studies with different doses and different designs.

The Lilly ad figures come from a single trial that compared Zepbound directly with lower doses of Wegovy ^[1]. The 7.2 mg Wegovy figure of about 19% comes from a Novo-run study, and no head-to-head trial of 7.2 mg Wegovy against Zepbound has been reported ^[1]. That means a patient comparing the two sets of percentages is looking at results from separate studies, not a direct comparison of the two medicines.

For people weighing injectable versus pill options, both companies now market an oral product: the Wegovy pill (semaglutide) and Foundayo (orforglipron) ^[1]. Nothing in the dispute changes what the FDA has approved. It has not been reported whether the ad claims have been reviewed by regulators.

What happens next

No court dates, hearing schedule or expected timeline for a ruling in Novo's lawsuit has been reported ^[1]. Also not disclosed: whether either company has sought a settlement, and whether Novo plans to run advertising that highlights the 7.2 mg Wegovy data. Lilly has said it stands behind the head-to-head trial data it uses in ads ^[1].