Novo Nordisk asks court to pause Eli Lilly's GLP-1 advertising

Novo Nordisk asked a federal judge on August 14, 2026 to halt Eli Lilly's current obesity and diabetes advertising while the companies' dispute plays out in court ^[1]. The motion for a preliminary injunction was filed in the U.S. District Court for the District of New Jersey, and the court set it for consideration three days later, on August 17 ^[1]. No decision has been reported ^[1].

The request grows out of a lawsuit Novo filed on July 21, 2026, accusing Lilly of false advertising and unfair competition under the Lanham Act and state law ^[2][3]. The case turns on which doses Lilly's ads place side by side. One campaign compares Zepbound (tirzepatide) at its maximum tolerated 10 mg and 15 mg doses with Wegovy (semaglutide) at 1.7 mg and 2.4 mg; another compares Mounjaro (tirzepatide) at 15 mg with Ozempic (semaglutide) at 1 mg ^[2]. Novo says both leave out higher doses of its own medicines: a 7.2 mg Wegovy injection the FDA approved in March 2026, and a 2 mg Ozempic maintenance dose approved more than four years ago ^[2]. One ad tells viewers that patients on Zepbound lose an average of 50 pounds, compared with 33 pounds on the 2.4 mg Wegovy dose ^[1].

The two companies point to different trials. Novo cites STEP UP (NCT05649137), a 72-week study of 1,407 adults with obesity, in which the 7.2 mg Wegovy dose produced a mean weight reduction of about 18.8%, or roughly 47 pounds, versus 3.9% for placebo ^[2]. Lilly's advertising draws on SURMOUNT-5 (NCT06047548), described as the first head-to-head trial of the two drugs, which reported about 20.2% mean weight loss with tirzepatide against 13.7% with semaglutide over 72 weeks in 751 adults who had obesity or were overweight; semaglutide was tested at the 1.7 mg and 2.4 mg doses available when the trial was designed ^[2]. No study has yet compared each drug's highest dose against the other's ^[2].

Novo is not asking the court to stop Lilly from selling or advertising GLP-1 medicines at all ^[1]. The motion targets specific comparative claims and seeks corrective advertising, with Novo arguing the campaigns have "planted false beliefs in consumers' minds that will persist long after the ads stop running" ^[1]. The underlying suit seeks a permanent injunction and a corrective campaign ^[2][3]. Novo sent Lilly a cease-and-desist request before filing and says Lilly declined to pull or meaningfully correct the ads ^[2].

Lilly denies wrongdoing. It says it stands "firmly behind our advertising," calls a well-designed head-to-head trial "the gold standard for comparing medicines," and describes its messaging as "truthful," "transparent," and "grounded in the most direct scientific evidence available" ^[1][2]. Lilly also says Novo is asking a court to block the sharing of trial results rather than compete on the merits ^[2].

Analysts expect the U.S. obesity drug market to be worth more than $100 billion by the end of the decade ^[3]. BMO analyst Evan Seigerman said the suit looks like a way for Novo to try to change public perception of how the two companies' drugs perform, while OrbiMed's Sven Borho said going to court would not help Novo in a marketing battle ^[3].

Why it matters for patients

Many patients meet these numbers in television and social media ads well before a clinician walks them through what the figures mean, and that gap is what the case is about. Hana Kahleova, director of clinical research at the Physicians Committee for Responsible Medicine, told Pharmacy Times that when an ad "puts a maximum dose of one product against a starting or midrange dose of the competitor, it's not really telling you which drug works better; it's telling you which doses the advertiser chose to show" ^[2].

She added that higher doses of semaglutide or tirzepatide generally produce more weight loss than lower doses of the same drug, so either medicine can be made to look stronger or weaker depending on the doses chosen for a comparison ^[2]. Because the 7.2 mg Wegovy dose has not been tested head to head against tirzepatide, she said choices between the two rest on factors such as gastrointestinal tolerability, dosing schedule, cost and insurance coverage, and other health conditions rather than a settled answer about which drug wins at those doses ^[2].

Nothing in the filings claims either medicine is unsafe or ineffective; the argument is about advertising, not new clinical evidence about the drugs ^[1]. The case is also unfolding alongside wider federal scrutiny of GLP-1 promotion: the FDA's Office of Prescription Drug Promotion has sent warning letters to Lilly, Novo Nordisk, and Hims & Hers over marketing materials ^[2].

What happens next

The preliminary injunction motion is pending, with the court scheduled to consider it on August 17, 2026 ^[1]. The New Jersey case continues, and no trial date has been set ^[1]. Accounts of the injunction request differ: one dates the filing to August 14 with a court date of August 17 ^[1], an August 24 pharmacy trade article described Novo as having signaled it would seek such an order ^[2], and other reporting says Novo is seeking a preliminary injunction without giving a filing date ^[3].