By: Mass Tort Lawyers Keith E. Donovan and Matthew R. Fogg
On June 4, 2026, a federal panel combined all of the Dupixent lawsuits into one case, in front of one judge: Judge Zahid N. Quraishi, in the U.S. District Court for the District of New Jersey. The case is called MDL No. 3180. You can read the court's order here. This matters to you if you or a family member took Dupixent and were later diagnosed with a T-cell lymphoma like CTCL.
This is a positive step, but it's worth understanding what it does and doesn't mean. It does not mean you're automatically part of anything, and no case has been settled or gone to trial yet. Below, we'll walk through what's happened so far and what it could mean for you or your family.
What Is an MDL?
You may have heard the term "class action" and assumed that's what this is. It isn't. In an MDL (short for multidistrict litigation), your case stays your own case. No one else's outcome decides your outcome. What changes is where the case is handled: instead of many separate lawsuits sitting in courts all over the country, they're now grouped in front of one judge so the early legal work — like gathering evidence and hearing from medical experts — only has to happen once, rather than dozens of times over.
Every case in this MDL is asking the same basic question: did Sanofi and Regeneron, the companies that make Dupixent, know (or should they have known) that the drug could cause or worsen CTCL — and did they fail to warn patients and doctors about it? Part of the concern is that Dupixent can calm skin symptoms without stopping an underlying lymphoma, making it harder to catch early. You can read more about how this masking effect works on our site.
If you want more on how these claims work and who they may apply to, our Dupixent lawsuits FAQ walks through it in plain language.
How We Got Here
This didn't happen overnight. Back in February 2026, attorneys for the first patients who filed suit asked the federal court system to combine the cases. Sanofi and Regeneron agreed that combining the cases made sense — they just didn’t agree on where. The judges heard both sides argue it out in late May 2026, and ultimately, to the satisfaction of plaintiffs’ counsel, chose New Jersey.
More lawsuits are expected to join this same group as more patients come forward with a CTCL or related diagnosis.
What Happens Next
Now that the cases are grouped together, the next phase is called discovery — this is where both sides gather medical records, documents, and expert opinions. Judge Quraishi's court will oversee this process for every case in the group.
After that, a handful of individual cases are usually chosen to go to trial first. These are called bellwether trials. They're not a final decision on everyone's case, but they help both sides understand how a jury is likely to react to the evidence, which often shapes what happens with the rest of the cases going forward.
Here is where things actually stand today: no case has settled, and no case has gone to trial. If someone promises you a specific dollar amount, they're getting ahead of what's actually happened in court.
What This Means for You or Your Family
If you took Dupixent and were later diagnosed with cutaneous T-cell lymphoma, mycosis fungoides, or Sézary syndrome, there is now a clear, established path for your case in federal court. But deadlines still apply, and they're not the same for everyone — they depend on where you live and when you were diagnosed. The sooner your medical records and treatment history are reviewed, the better your chances of building a strong case. If you're not sure whether you qualify, our page on who is eligible to file a Dupixent lawsuit breaks down the criteria and timing in more detail.
Talk to a Dupixent Lawsuit Lawyer Today
If you or someone in your family developed lymphoma after taking Dupixent, do not wait to have your case reviewed. Filing deadlines are firm, and medical records become harder to gather the longer you wait. Learn more about how we're handling these claims on our Dupixent lawsuits page.
