Court filings in MDL No. 3180 gather federal lawsuits by eczema patients later diagnosed with cutaneous T-cell lymphoma after Dupixent use. The suits allege Sanofi and Regeneron failed to warn about that risk. The filings create shared pretrial proceedings, not a finding that Dupixent causes the disease.
MDL means multidistrict litigation. It sends related federal cases to one judge for joint pretrial steps. On June 4, 2026 the Judicial Panel on Multidistrict Litigation centralized these cases in the District of New Jersey before Judge Zahid N. Quraishi, according to the JPML transfer order.
Table of Contents
- Which lawsuits are included?
- What warning issue is at stake?
- Does this prove Dupixent causes lymphoma?
- What should patients and families do now?
Which lawsuits are included?
The JPML transfer covered 15 actions from 12 districts plus seven potential tag-along cases. JPML statistics later listed 38 pending MDL-3180 actions on Oct. 1, 2026.
Plaintiffs are people treated with Dupixent for eczema or atopic dermatitis. They later received diagnoses of cutaneous T-cell lymphoma, including mycosis fungoides and Sezary syndrome. LegalScoops reports the claims name Sanofi and Regeneron and allege failure to warn.
What warning issue is at stake?
The core allegation is failure to warn about CTCL risk. Plaintiffs say the label did not alert doctors and patients in time to act. The current U.S.
prescribing information's Warnings and Precautions section was last revised in April 2026, according to National Library of Medicine DailyMed. It lists hypersensitivity and other risks but contains no lymphoma or CTCL warning. FDA placed Dupixent-CTCL on its October-December 2024 FAERS quarterly signal list as a potential serious-risk signal, according to the FDA signal notice mirrored by EIN Presswire. The agency said it was evaluating whether regulatory action was needed.
Does this prove Dupixent causes lymphoma?
No. MDL centralization decides only that shared pretrial work will improve efficiency. It does not decide causation or fault.
LegalScoops reports the makers dispute causation and no trial verdict or causation finding has been reported. Early CTCL can look like eczema, according to a Healio dermatology Q&A, which complicates individual histories. A 2025 Dermatitis review of 35 reports could not separate drug-caused cancer from unmasked preexisting lymphoma. That limit affects how doctors and courts view new diagnoses made after Dupixent treatment starts.
What should patients and families do now?
People with atypical or hard-to-treat eczema need a clear diagnosis before starting treatment. Keep records of prior rashes, biopsies, treatment dates, and pathology reports. Specialists cited in the Healio dermatology Q&A describe practical steps for this setting: Bring medication history, biopsy slides, and diagnosis timeline to any medical or legal consultation.
- Ask about biopsy for atypical, persistent, or worsening patches before Dupixent
- Seek prompt review of new lumps, thick plaques, or spreading redness during treatment
- Stop Dupixent if CTCL is confirmed and follow the treating doctor's plan
- Report the event through FDA MedWatch and keep all pharmacy records