Novo Nordisk and Eli Lilly argue federal preemption in 4,000-case GLP-1 MDL
Manufacturers of Ozempic and Mounjaro are arguing federal law blocks state failure-to-warn claims in a 4,000-case MDL, a defense that could decide thousands of cases at once.
Manufacturers of Ozempic, Wegovy and Mounjaro filed summary judgment briefing on April 30, 2026 in the federal proceeding that consolidates more than 4,000 claims that GLP-1 drugs caused stomach paralysis and other gastrointestinal injuries. Among the defenses they pressed was that federal law preempts state failure-to-warn claims [1].
The briefing is part of MDL 3094, before Judge Karen S. Marston in the Eastern District of Pennsylvania. The MDL was created in February 2024 [1]. Briefing continued through July 2026. When Judge Marston will rule has not been reported, and no decision has been announced.
Preemption is described as a cross-cutting defense, meaning the manufacturers are arguing it applies across the litigation rather than case by case [1]. If a court accepts it, failure-to-warn claims — the core of many of the suits — could be resolved without individual patients' medical histories being weighed. The outcome has not been reported.
Where the litigation stands
As of September 2026, 4,022 cases were pending in MDL 3094, out of 4,056 total filed. That is growth of 202% since January 2025 [1].
About 75% of complaints allege gastroparesis, or stomach paralysis; 18% allege ileus; and 8% allege gallbladder injuries [1]. Defendants include Novo Nordisk, which makes Ozempic, Wegovy and Rybelsus, and Eli Lilly, which makes Mounjaro, Zepbound and Trulicity [1].
A separate proceeding, MDL 3163, handles vision-loss claims known as NAION. It was created in December 2025, is also before Judge Marston, and covers about 200 cases [1].
Regulatory background
In October 2025, the FDA added language to the Ozempic label stating that the drug "is not recommended in patients with severe gastroparesis" [1]. Earlier label changes included an ileus warning in September 2023 and a pulmonary aspiration warning in January 2025 [1].
Plaintiffs argue the labels did not adequately warn that delayed stomach emptying — an intended effect of the drugs — could persist or progress into serious disease [1]. A 2023 study by Sodhi and colleagues in JAMA reported higher risks among patients using GLP-1 drugs for weight loss: 3.67 times for gastroparesis, 4.22 times for bowel obstruction and 9.09 times for pancreatitis [1].
Why it matters for patients
Nothing in this briefing changes who can be prescribed these drugs or how they are dispensed. But preemption is the kind of defense that, if it succeeds, could end failure-to-warn claims without individual cases being heard [1]. If it fails, the litigation continues on its current path.
For patients who have filed or are weighing a claim, the timeline is long. Expert depositions finished in April 2026, and Daubert motions — challenges to whether expert testimony can be used at trial — were fully briefed as of the April 28, 2026 deadline [1]. First bellwether trials are expected in mid-to-late 2026, and the source describes mass settlements as unlikely before late 2027 [1]. No settlements have been announced [1].
Gastroparesis claims face a separate hurdle. Judge Marston has required objective diagnostic testing for those claims, and the standard generally used is a gastric emptying study showing more than 10% retention at four hours [1].
Legal analysts estimate total liability across both MDLs could exceed $2 billion [1]. That is an estimate, not a finding by any court.
What happens next
Sources
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