Dupixent CTCL Investigation

Dupixent Investigation: Skin Cancer Linked to Inflammatory Disease Treatments

Robins Kaplan LLP is investigating claims of individuals who have had at least two injections of Dupixent® (dupilumab) and have been diagnosed with cutaneous T-cell lymphoma (CTCL), a rare type of skin cancer. Manufacturers of the drug may have failed to adequately warn users about possible connections to CTCL. 

If you or a loved one used Dupixent and have been diagnosed with CTCL, contact our mass tort attorneys for a free case evaluation at 1.800.207.6225 or complete our online contact form.

What Is Dupixent?

Dupixent is a brand name of the drug known as dupilumab. Dupixent is a prescribed injection intended to treat moderate-to-severe type 2 inflammatory diseases. Such diseases include atopic dermatitis (eczema), asthma, rhinosinusitis with nasal polyps, prurigo nodularis, and other conditions. 

Global partners Regeneron Pharmaceuticals, Inc. and Sanofi-Aventis manufactured the drug, and the U.S. Food and Drug Administration first approved it in 2017. 

Studies Show Connection Between Dupixent and CTCL

Medical studies report a number of patients who were treated with Dupixent for eczema and later received a CTCL diagnosis. There may be a growing link between the two, as research shows an increased risk of CTCL for Dupixent users and a possible acceleration of underlying lymphoma due to the drug’s use. 

Furthermore, users may have mistaken their CTCL for eczema and continued using Dupixent while the cancer went untreated.

Types of CTCL Dupixent Users May Have

There is a range of CTCL subtypes that Dupixent users may have developed. The two most common types of CTCL include mycosis fungoides and Sezary syndrome. 

Other types of CTCL include: 

• Lymphomatoid papulosis
• Subcutaneous panniculitis-like T-cell lymphoma
• Primary cutaneous anaplastic large cell lymphoma
• Extranodal NK/T-cell lymphoma
• Primary cutaneous gamma/delta T-cell lymphoma

CTCL Signs and Symptoms 

Symptoms of CTCL can develop slowly over years and often resemble common skin conditions like eczema or psoriasis.

• Persistent red, pink, brown, or gray patches
• Dry, scaly, or flaky skin
• Itching (sometimes severe)
• Hair loss
• Plaques (thicker, raised areas)
• Rash that doesn’t improve with typical eczema treatments
• Skin changes that come and go
• Skin that becomes darker or lighter in affected areas
• Thickened skin on palms or feet

Reports of Dupixent and CTCL in Publications

In April 2024, the Journal of the American Academy of Dermatology published a study that found that patients with atopic dermatitis treated with dupilumab (Dupixent) had a higher risk of developing CTCL. 

Then, in August 2024, the National Library of Medicine published findings that, among patients with atopic dermatitis matched for age, race, and sex, those treated with dupilumab had a relative risk (RR) of 4.59* for developing CTCL compared with patients who never received dupilumab. The incidence of CTCL was 0.28% in the dupilumab cohort versus 0.061% in the non-dupilumab cohort.

Another publication suggests a possible mechanistic link (based on immune signaling data) that could help explain why CTCL cases have appeared more frequently than expected in some patients treated with dupilumab.

*A relative risk of 4.59 means that, in this study population, patients treated with dupilumab were about 4.59 times more likely to be diagnosed with CTCL than those who were not treated with dupilumab.

Does Dupixent Include a Warning of CTCL Risk? 

In March 2025, the U.S. FDA added Dupixent to its quarterly “Potential Signals of Serious Risks” list after receiving hundreds of adverse event reports linking the drug to CTCL and confirmed it was evaluating the need for regulatory action. 

Despite these signals, current FDA-approved labeling for Dupixent does not specifically warn about CTCL. There is also longstanding clinical recognition that CTCL frequently mimics eczema, raising concerns that skin cancers may have been misdiagnosed before or during dupilumab treatment.

Dupixent-CTCL Concerns: FAQs

Can Dupixent cause lymphoma?

While definitive proof has yet to be established, some studies and case reports have identified an association between dupilumab use and subsequent diagnoses of CTCL.

What is the risk of CTCL?

One large matched-cohort study reported a relative risk of approximately 4.59 for CTCL among dupilumab users compared with non-users. Though, the absolute incidence remained low (about 0.28%).

How long after starting Dupixent was CTCL diagnosed in reported cases?

In published case reports and cohort analyses, CTCL has been diagnosed from months to a few years after initiating dupilumab therapy. Some cases were identified within the first year of treatment.

Has the FDA issued a warning?

As of now, the FDA has not added a specific CTCL warning to Dupixent’s prescribing label. However, it has listed the drug under evaluation for a potential safety signal related to CTCL.

Why Choose Robins Kaplan to Investigate Your Claim?

Wondering if you have a Dupixent case? The team at Robins Kaplan can help. We guide each client through the ins-and-outs of their case, helping them understand the complexities of their legal claims. We answer questions and address concerns while developing comprehensive plans that approach each case with care and strategic solutions.

Our attorneys have extensive experience handling defective drug or medical device cases, from our groundbreaking lawsuit against the tobacco industry to representing more than 500 women in the Dalkon Shield litigation. 

Connect with us using the online form or call us at 1.800.553.9910.