Mylan sues Novo Nordisk in Delaware seeking a non-infringement ruling for its generic Wegovy

Mylan Pharmaceuticals has filed a lawsuit in Delaware federal court asking a judge to rule that its proposed generic version of Novo Nordisk's weight-loss drug Wegovy does not infringe a Novo patent. The complaint, filed September 24, 2026, is the latest move in a broader intellectual property battle over the GLP-1 medicine ^[1].

Wegovy is the brand name for semaglutide approved for weight management. Novo also sells semaglutide as Ozempic for type 2 diabetes; both use the same molecule but are approved at different doses for separate indications ^[3].

The new filing asks for a declaration of non-infringement rather than waiting to be sued. Which specific patent is at issue in the September 2026 case has not been disclosed ^[1].

A fight that started in 2023

Novo first sued Viatris — Mylan's parent company — over its generic semaglutide plans in January 2023, shortly after Viatris filed its generic application with the FDA ^[3]. Novo accused Mylan of running afoul of five patents in total ^[3].

Viatris pushed back on two fronts: in court, and by challenging the Novo patents at the U.S. Patent and Trademark Office, where it got mixed results ^[3]. In October of the prior year, Novo and Mylan reached an undisclosed settlement over Mylan's proposed Ozempic generic ^[3].

One of the central patents, known as the #003 patent, covers a method for reducing body weight by administering semaglutide once weekly "in an amount of at least 0.7 mg and up to 1.6 mg" where the semaglutide is "administered without another therapeutic agent" ^[4]. In a March 25, 2024 claim construction order in case No. 23-cv-00101, the Delaware court read the dosing term to mean doses "greater than or equal to 0.7 mg and never to exceed 1.6 mg," and read the second term to mean administered without another therapeutic agent as part of the method for reducing body weight or for treating diabetes or hypertension ^[4].

The July 2025 ruling

On July 23, 2025, a Delaware federal judge found that the proposed labeling for Mylan's generic does not recommend that doctors prescribe it in a way covered by that Novo patent ^[2]. Novo had not directly accused Mylan of infringing the #003 patent; instead it argued the generic's label could prompt doctors and patients to use the drug in an infringing way ^[3].

Mylan's proposed label says its semaglutide generic "should not be used in combination with other semaglutide-containing products or any other GLP-1 receptor agonists" ^[3]. Because that instruction excludes only a specific set of drugs, the court found the label "does not state, imply, or suggest in any way that Mylan's semaglutide product should be administered without any other therapeutic agent to reduce weight loss or to treat diabetes or hypertension" ^[3].

A Novo Nordisk spokesperson said at the time, "As this case is ongoing, we cannot provide any further comment" ^[3]. A Viatris spokesperson said the company was "pleased with the District Court's favorable decision finding non-infringement of the '003 patent related to Wegovy, which removes it from the patent trial scheduled to begin in March 2026" ^[3].

Why it matters for patients

Generic competition is the main mechanism that lowers US drug prices, and these lawsuits determine when — or whether — a generic can launch. Each patent that a generic maker clears removes one barrier; each one it loses can push a launch years out.

Several things are still unsettled. Viatris' Wegovy generic has not secured FDA approval ^[3]. Branded Wegovy could lose US patent protection in 2032, according to Novo's 2024 annual report ^[3]. So even a favorable court ruling for Mylan would not by itself put a generic on pharmacy shelves, and no launch date has been announced.

It is also worth noting what these cases are not about. The disputes concern patent scope and label wording, not the safety or effectiveness of semaglutide. Separately, Novo has pursued litigation against telehealth firms, med spas, pharmacies and weight-loss clinics selling compounded semaglutide, which the company has argued is potentially unsafe and violates US compounding laws ^[3].

What happens next

The outcome of the patent trial that had been scheduled to begin in March 2026 has not been reported ^[3]. Novo has not publicly responded to the September 2026 declaratory judgment complaint, and no hearing schedule in that case has been disclosed ^[1].