Eli Lilly asks judge to end all injury claims over Trulicity, Mounjaro and Zepbound

Eli Lilly moved on May 19, 2026 to end patient injury lawsuits over Trulicity, Mounjaro and Zepbound across every injury category in the federal GLP-1 litigation, in a filing that lays out 11 motions to disqualify plaintiffs' expert witnesses and win summary judgment ^[1].

The document is titled an "Introductory Roadmap Brief to Issue 2 and 3 Motions" and was submitted in In re: Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RAs) Products Liability Litigation, MDL No. 3094, before Judge Karen Spencer Marston in the Eastern District of Pennsylvania ^[1]. It proposes an order for the court to review the motions; it does not announce a decision, and no allegation in the case has been decided on the merits ^[1][2]. That MDL, consolidated in September 2023, handles gastrointestinal injury claims, while a companion case, MDL 3163, covers alleged vision loss ^[2].

The products and the claims

Lilly lists three of its medicines as the products at issue: Trulicity (dulaglutide), approved in September 2014 for type 2 diabetes; Mounjaro (tirzepatide), approved in May 2022 for type 2 diabetes; and Zepbound (tirzepatide), approved in November 2023 for chronic weight management ^[1]. Trulicity added an indication to reduce major cardiovascular events in type 2 diabetes patients in 2020, and Zepbound was approved in 2024 to treat obstructive sleep apnea in certain patients ^[1]. Mounjaro and Zepbound activate both the GLP-1 and the glucose-dependent insulinotropic polypeptide (GIP) receptors ^[1].

Plaintiffs allege Lilly failed to warn adequately about gastroparesis, gallbladder disease (gallstones and gallbladder inflammation), ileus (halted bowel motility) and intestinal obstruction (bowel blockage), among other injuries ^[1]. The general-causation phase of the case is limited to four alleged injuries — gastroparesis, ileus, small bowel obstruction and gallbladder injuries — while the warning-adequacy phase has no such limit, according to the brief ^[1]. Other injuries named in the filing include pancreatitis, malnutrition, micronutrient deficiencies, Wernicke's encephalopathy, muscle wasting, dehydration, acute kidney injury and aspiration ^[1].

How the motions break down

Six of the 11 motions target expert testimony: gastroparesis causation opinions (motion 1); warning adequacy and preemption opinions from Dr. David Metz and Dr. David Ross (motion 3); warning adequacy opinions from former FDA commissioner Dr. David Kessler (motion 4); ileus and obstruction causation opinions (motion 5); gallbladder causation opinions from Dr. Gabriel Lang (joint motion 7); and mechanism-of-action and animal-study opinions from Dr. Jeffry Lansman and Dr. Kevin O'Brien (joint motions 10 and 11) ^[1].

Four ask for summary judgment: gastroparesis claims (motion 2), ileus and obstruction claims (motion 6), gallbladder claims (motion 8), and other gastrointestinal and miscellaneous claims (motion 9) ^[1]. Motions 7, 10 and 11 are joint filings with Novo Nordisk ^[1]. Lilly proposes taking up gastroparesis first, noting those claims remain more than 60% of the MDL cases against it ^[1]. Ten disclosed experts have Lilly-related opinions, the brief says, and Dr. David Madigan's report and opinions as to Lilly were withdrawn after his deposition ^[1].

The preemption argument

To win on preemption, Lilly must show either that there was not enough "newly acquired information" for it to change an FDA-approved label on its own, or that there is "clear evidence" the FDA would have rejected a different warning, the brief states ^[1]. On gastroparesis, it asserts the FDA considered and rejected additional warnings ^[1]. For malnutrition, micronutrient deficiency, Wernicke's encephalopathy and muscle wasting, it says there is clear evidence the agency would have rejected — and did reject — added warnings ^[1]. For all claims, it says no newly acquired information existed that would have permitted a unilateral label change ^[1].

The brief also stresses that plaintiffs' expert opinions are limited by condition, medicine or time period ^[1]. Dr. Kessler and Dr. Ross offer no opinions about tirzepatide, the active ingredient in Mounjaro and Zepbound ^[1]. Dr. Kessler's Trulicity opinions cover ileus from 2017/2018 through November 2022, and intestinal obstruction and constipation including fecal impaction from 2017/2018 through March 2026 ^[1]. Dr. Ross's gallbladder opinions address only Trulicity labels from December 2017 through June 10, 2022 ^[1]. Plaintiffs have confirmed Dr. Kessler is not offering an opinion on Lilly's Section 5 warnings at summary judgment ^[1]. For some alleged injuries, including malnutrition and pancreatitis, plaintiffs put forward no warning-adequacy expert at all, according to the filing ^[1].

Separately, Novo Nordisk filed its own May 19 roadmap brief, and both companies deny the allegations ^[2]. As of May 20, the FDA had received more than 207,000 adverse event reports tied to Ozempic, Wegovy, Zepbound and Mounjaro, according to one account of the litigation ^[2].

Why it matters for patients

The filing is a step in the pretrial fight over evidence, not a change in medical practice. It does not alter any FDA-approved label, and no label change has been reported ^[1]. What it signals is that the case now hinges on expert testimony. Lilly argues that showing a medicine can cause an alleged injury — general causation — requires admissible expert evidence, and that warning-adequacy claims generally need it too ^[1]. If the judge excludes central causation experts or accepts the preemption arguments, the litigation could narrow substantially before any trial; if she rules the other way, the cases move closer to live testimony ^[2].

What happens next

Lilly says it will file its motion 4 brief, on Dr. Kessler's opinions, by May 27, 2026 ^[1]. On April 30, Judge Marston set deadlines for expert challenges and summary-judgment motions on warning adequacy, federal preemption and general causation ^[2]. Sessions to hear those motions are expected over the next several months, and her rulings could narrow the MDL ^[2]. No trial date has been reported.