Novo Nordisk v. Eli Lilly — Court Refuses to Block Comparative GLP-1 Ads

Background

Novo Nordisk and Eli Lilly compete in the market for GLP-1 medicines used to treat obesity and type 2 diabetes. Novo sells Wegovy and Ozempic, while Lilly sells Zepbound and Mounjaro. Lilly ran national advertisements comparing results from its clinical trials with results for Novo’s products, including a claim that patients using Zepbound lost an average of 50 pounds compared with 33 pounds for patients using Wegovy at doses up to 2.4 milligrams.

Novo argued that those comparisons became misleading after the Food and Drug Administration approved a 7.2-milligram Wegovy dose that had not been included in Lilly’s earlier head-to-head trial. Novo sued under the Lanham Act and New Jersey law, asking the court to stop the advertisements and require corrective advertising. After a two-day evidentiary hearing, the court considered testimony and evidence about the trials, consumer understanding, prescription volumes, and both companies’ advertising practices.

The Court’s Holding

Judge Zahid N. Quraishi denied the preliminary injunction. A party seeking that extraordinary remedy must establish both a reasonable probability of success and irreparable injury that is actual and imminent. Novo failed at the irreparable-harm gateway.

Even assuming Novo’s merits showing triggered the Trademark Modernization Act’s rebuttable presumption of irreparable harm, Lilly produced enough evidence to make that presumption disappear. Prescription data showed that sales volumes for Ozempic and Wegovy remained stable while the challenged advertisements ran. Novo delayed bringing suit, and its own annual report assigned a value to goodwill that Novo’s witness claimed was nearly impossible to quantify.

Once the burden returned to Novo, its proof remained speculative. Novo asserted that the advertising threatened future sales and damaged its clinical reputation and goodwill, but it did not supply supporting consumer insights or other evidence of an immediate injury. Its witness acknowledged that he had not attempted to measure the claimed harm. The court also found that money damages could address any nontrivial injury that might later be proven.

The court added an independent equitable reason for denial: unclean hands. Novo had continued making superiority claims from an older clinical trial after Lilly obtained approval for higher Trulicity doses, and Novo’s advertisements did not disclose that those higher doses were available or untested. Novo stopped those advertisements only days before filing suit. Because Novo had used a closely related strategy, the court would not grant the equitable relief it sought against Lilly.

Although a full merits ruling was unnecessary, the court noted that Novo’s preliminary case was not persuasive. Lilly’s advertisements disclosed the available 7.2-milligram Wegovy dose and said it was not studied; Lilly challenged the design of Novo’s consumer-confusion studies; and Novo’s theory did not fully account for physicians’ role in selecting prescription medicines.

Key Takeaways

• A Lanham Act plaintiff seeking an early injunction needs evidence of immediate, non-speculative injury, not only assertions about lost goodwill or future sales.
• The Trademark Modernization Act’s presumption of irreparable harm can disappear when the defendant produces even a modest evidentiary showing against likely injury.
• Stable prescription data, delay in suing, and a plaintiff’s own valuation of goodwill can undermine claims that advertising is causing urgent, unquantifiable harm.
• A company asking equity to stop a competitor’s comparative advertising may face an unclean-hands defense if it recently used a materially similar strategy.

Why It Matters

The opinion shows that disputes over scientific advertising comparisons are not resolved solely by debating which study is newer or more rigorous. At the preliminary-injunction stage, the plaintiff must connect the challenged message to an injury that is happening now and cannot later be repaired with damages.

For businesses making comparative claims, clear disclosures about doses and study limits can matter. For competitors challenging those claims, reliable market evidence and consistent advertising practices are equally important. The underlying false-advertising case continues, but Lilly may keep running the challenged campaign while the merits are litigated.

Surfaced via Law360 IP.