North Carolina Product Liability Lawyer Blog
In 2017, the U.S. Food and Drug Administration (FDA) approved dupilumab (which goes by the brand name Dupixent) as a treatment for atopic dermatitis (commonly known as eczema). However, recent research has identified a possible link between Dupixent and cutaneous T-cell lymphoma (CTCL), a type of cancer. If you have taken (or are taking) Dupixent, you should be aware of this potential link and discuss the risks with your doctor.
An Overview of Dupixent
Regeneron Pharmaceuticals and Sanofi worked together to develop Dupixent. Dupixent is a monoclonal antibody, which means it’s a biologic, or medicine made from living organisms or parts of living organisms. It’s administered as an injection and is often used to treat moderate to severe cases of eczema where more topical treatments have been unsuccessful or aren’t possible. Dupixent is also used to treat:
- Asthma
- Chronic rhinosinusitis with nasal polyps
- Eosinophilic esophagitis
- Chronic obstructive pulmonary disease
- Chronic spontaneous urticaria
- Bullous pemphigoid
- Prurigo nodularis
Dupixent works by blocking interleukins (a type of protein) from binding to cell surface receptors. Specifically, it focuses on interleukins 4 and 13, which are often produced by the body’s immune system and have been found to play a key role in the body’s inflammatory process.
Despite the wide array of conditions Dupixent can be prescribed to treat, its link to CTCL is most well-known when used with patients dealing with eczema.
Cutaneous T-Cell Lymphoma
Even though CTCL is most readily observed through its effect on the skin, it’s a type of non-Hodgkin lymphoma, or blood cancer. CTCL starts in the body’s immune system by affecting T cells. These T cells then become mutated and attack the skin. This can lead to skin lesions or rashes that sometimes get confused with eczema. Besides the appearance of eczema, other signs and symptoms of CTCL include:
- Scaly, itchy skin patches.
- Skin discoloration.
- Lumps on the skin that may or may not break open.
- Hair loss.
- Enlarged lymph nodes.
- Thickened skin on the palms of the hands and soles of the feet.
There are several different types of cutaneous T-cell lymphomas, but the two most common variants are:
- Mycosis fungoides: A slower-growing variant of CTCL, where the skin is the primary part of the body that’s affected by CTCL.
- Sézary syndrome: A faster-growing variant of CTCL where the cancerous T cells affect not just the skin, but the blood as well. Mycosis fungoides can sometimes turn into Sézary syndrome, and a common distinction between these two types of CTCL is that individuals with Sézary syndrome will have a skin rash that affects the entire body.
It’s unknown what exactly causes CTCL, but CTCL is more common in those who are male, aged 50 or older, and/or are Black.
The Link Between Dupixent and CTCL
Several studies have found a link between Dupixent and CTCL. In one study, researchers observed that individuals who took Dupixent to treat their eczema were more than four times more likely to develop CTCL. Another study found that this increased risk was more pronounced in older adult patients, and most of the CTCL diagnoses occurred within the first year of taking Dupixent. Then there’s a study which suggests that Dupixent may accelerate the progression of existing CTCL.
This is unsettling research, but more research needs to be done. One of the key issues is the fact that some individuals with CTCL will sometimes be misdiagnosed as having eczema.
Assuming people with CTCL are being misdiagnosed as having eczema and are therefore being prescribed Dupixent, does that fully explain the data that shows individuals taking Dupixent are more than four times more likely to have CTCL? If it does, then the next question is what effect, if any, does Dupixent have on how quickly CTCL progresses within the body?
There’s data that shows some people with CTCL who take Dupixent experience a worsening of CTCL symptoms.
Another possibility is that Dupixent actually causes CTCL, but again, we need more studies on this potential causation.
Potential Legal Action
Legal action has begun, but it is in the early stages. There’s been one notable case, Richardson v. Regeneron Pharmaceuticals that was filed on October 1, 2025 in U.S. District Court for the Middle District of Tennessee. The plaintiff is the daughter of a patient who took Dupixent and allegedly died as a result.
The plaintiff sets forth several causes of action, most notably that there was a failure to warn the plaintiff’s mother that taking Dupixent would increase the risk of developing CTCL or accelerate the progression of CTCL that already existed in the body.
If it turns out there’s a definitive link between CTCL and Dupixent, given the sheer number of people (hundreds of thousands) who have taken this medication, there could be an avalanche of lawsuits in the future.
As for the continued marketing and use of Dupixent, the FDA has taken minimal action so far. The most notable event so far has been the FDA adding Dupixent to the list of medications where the “FDA is evaluating the need for regulatory action.”
If there are any major developments concerning Dupixent, whether within the scientific or legal community, I’ll let you know. In the meantime, if you have any medical-related questions about taking this medication, you should talk to your primary care provider. If you have any legal questions, I’m more than happy to help. You can call me at 919.334.6277 or contact me online to schedule a consultation.