Dupixent Lawsuit – Cancer Risk and CTCL Link

Introduction

Dupixent, also known by its generic name dupilumab, is a prescription medication widely prescribed to treat eczema, asthma, eosinophilic esophagitis, and other chronic inflammatory conditions. It works by blocking certain proteins that lead to inflammation. Dupixent has been approved by the FDA for multiple uses since 2017.

While marketed as a breakthrough therapy, recent medical studies and adverse event reports have linked Dupixent to serious risks, including Cutaneous T-Cell Lymphoma (CTCL) and other aggressive cancers. Lawsuits are now being filed alleging that the manufacturers, Sanofi and Regeneron, failed to adequately warn patients and physicians about these dangers.

If you or a loved one developed CTCL, Mycosis Fungoides, Sézary Syndrome, or another T-cell lymphoma after using Dupixent, you may qualify for legal action.

What is Dupixent?

Dupixent is a biologic medication administered via injection, typically every 1- 4 weeks, that works by targeting the immune system to reduce inflammation. It has been approved for the treatment of:

• Eczema (Atopic Dermatitis)
  
• Asthma
  
• Eosinophilic Esophagitis
  
• Chronic Rhinosinusitis with Nasal Polyps
  
• Chronic Spontaneous Urticaria
  
• Prurigo Nodularis 
• Bullous Pemphigoid
  
• Chronic Obstructive Pulmonary Disease (COPD)
  
  

Despite its widespread use, the FDA-approved labeling currently has no warnings for increased cancer risks.

Emerging Safety Concerns

While Dupixent has been hailed as a breakthrough biologic, multiple studies and adverse event reports now raise serious concerns about its long-term safety.

FDA Timeline and Label Issues

• Dupixent received multiple FDA approvals between 2017 and 2025 for conditions ranging from eczema and asthma to eosinophilic esophagitis and COPD (Drugs.com – FDA approval history).
  
  
• Despite its expanding use, the Instructions for Use (IFU) contain no warnings about increased cancer risks, even as evidence continues to mount (FDA Label, 2023).
  
  

Clinical Reviews and Reported Adverse Events

• A 2022 Clinical Review in Allergy & Immunology reported cases of CTCL progression as well as ophthalmic complications (dry eyes, conjunctivitis, keratitis), alopecia areata, and arthritis in Dupixent users (PubMed).
  
  
• These findings suggest Dupixent may trigger unintended immune system effects that extend beyond its intended therapeutic action.
  
  

Retrospective Studies (2024)

Two large-scale studies published in 2024 strengthened the link between Dupixent and lymphoma risk:

1. Journal of the American Academy of Dermatology (JAAD) study: Atopic dermatitis patients treated with Dupixent were 4.1 times more likely to be diagnosed with CTCL, even after discontinuing the drug. Notably, 27 of 41 patients were diagnosed more than one year after stopping treatment (JAAD, 2024).
   
   
2. Dermatologic Therapy review: An analysis of over 39,000 patients found Dupixent users were 4.59 times more likely to develop CTCL compared to controls. Nearly half of the patients diagnosed were under age 60, and 62% were diagnosed within the first year of use (Wiley Dermatologic Therapy, 2024).
   
   

FAERS Database Analysis (2025)

• An analysis published in the Journal of Allergy & Clinical Immunology (May 2025) reviewed the FDA Adverse Event Reporting System (FAERS).
  
  
• Dupixent showed a 30-fold higher proportional reporting ratio for CTCL compared to all other medications.
  
  
• The risk was especially elevated among men aged 45–65.
  
  
• Researchers concluded that “dupilumab may be unmasking or accelerating CTCL through the same immune pathways by which it improves atopic dermatitis.” (JACI, 2025).
  
  

Key Takeaway

The cumulative evidence suggests Dupixent may trigger, accelerate, or unmask Cutaneous T-Cell Lymphoma (CTCL) in susceptible patients. Despite repeated FDA approvals for new indications, the drug’s labeling still lacks cancer risk warnings. Patients and providers remain largely unaware of these risks, raising the stakes for ongoing litigation.

Grounds for Legal Action

Lawsuits allege that Regeneron and Sanofi:

• Failed to include adequate cancer risk warnings in Dupixent’s Instructions for Use (IFU).
  
  
• Marketed Dupixent as safe despite emerging evidence of lymphoma risks.
  
  
• Did not properly investigate or disclose adverse event data.
  
  

As a result, patients and families may have suffered delayed diagnosis, misdiagnosis (often mistaken for eczema), or progression of aggressive cancers.

Do You Qualify for a Dupixent Lawsuit?

You may be eligible to file a Dupixent claim if:

• You or a loved one took Dupixent, as prescribed, after 2017.
  
  
• You or a loved one took Dupixent for more than three months.
  
  
• You or a loved one were later diagnosed with CTCL or related T-cell lymphoma subtypes, including:
  
  
  • Mycosis Fungoides
    
    
  • Sézary Syndrome
    
    
  • Lymphomatoid Papulosis
    
    
  • Anaplastic Large Cell Lymphoma
    
    
  • Extranodal NK/T-cell Lymphoma
    
    
  • Subcutaneous Panniculitis-like T-cell Lymphoma
    
    
  • Adult T-cell Leukemia/Lymphoma
    
    
  • Follicular Helper T-cell Lymphoma
    
    
  • Peripheral T-cell Lymphoma
    
    
• Are within your state’s statute of limitations.

If you are unsure if you qualify for a claim, please do not hesitate to contact us. Our team of Intake Specialists can help determine if you qualify for a claim through our free case evaluation.

Contact Our Dupixent Attorneys

If you or a loved one developed CTCL or another T-cell lymphoma after using Dupixent, you may be entitled to financial compensation.

Nigh Goldenberg Raso & Vaughn is actively reviewing Dupixent cancer lawsuits nationwide. Our experienced mass tort attorneys can help determine if you qualify for legal action.

👉 Contact us today for a free case evaluation.

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