Can Dupixent Cause Lymphoma?

Evidence from multiple studies and case reports indicates that side effects of Dupixent (dupilumab) may increase the risk of rare T-cell lymphomas, with the strongest association seen in cutaneous T-cell lymphoma (CTCL). These cancers are serious, often misdiagnosed as eczema in their early stages, which delays proper treatment and allows the disease to progress. Survival outcomes vary widely by subtype and stage, but decline sharply once lymph nodes or internal organs become involved.

What is Cutaneous T-Cell Lymphoma (CTCL)?

CTCL is the most frequently reported cancer linked to Dupixent side effects. It is a rare form of non-Hodgkin lymphoma that originates in the skin’s T-cells, which normally help regulate the immune system. Instead of functioning properly, these malignant T-cells collect in the skin and form red, scaly patches, plaques, or tumors that often resemble eczema or psoriasis.

While CTCL begins in the skin, it is not confined there. As the disease progresses, cancerous T-cells can spread to:

• Lymph nodes (causing swelling in the neck, armpits, or groin)
• Bloodstream (particularly in Sézary syndrome, where malignant T-cells circulate widely)
• Internal organs such as the liver, spleen, or lungs in advanced stages

Due to this pattern, CTCL is considered both a skin disease and a systemic lymphoma once it advances beyond the skin. As a result of this pattern, CTCL is considered both a skin disease and a systemic lymphoma once it advances beyond the skin. Early-stage CTCL often has a favorable outcome, but once the disease spreads to lymph nodes or internal organs, 5-year survival falls to about 50%–60%.

Subtypes of CTCL Caused By Dupixent Side Effects

Several forms of CTCL have been identified among Dupixent users, each with unique features and outcomes:

• Mycosis fungoides: The most common CTCL subtype, typically slow-growing and confined to the skin in early stages. Over time, it can spread internally. Patients diagnosed in early stages often live 10+ years, but advanced MF carries a much poorer prognosis.
• Sézary syndrome: A rarer and more aggressive CTCL variant that involves malignant T-cells circulating in the blood and widespread skin involvement. Median survival is generally 2–4 years after diagnosis, reflecting its aggressive nature.
• Anaplastic large cell lymphoma (ALCL): An aggressive form of T-cell lymphoma that can affect skin (primary cutaneous ALCL) or internal organs and lymph nodes. Prognosis varies; cutaneous ALCL has relatively good survival with treatment, while systemic ALCL can be fatal if not promptly managed.
• Other rare subtypes: Reports have also linked Dupixent use with angioimmunoblastic T-cell lymphoma (AITL), adult T-cell leukemia/lymphoma (ATLL), and unclassified variants. These are highly aggressive cancers, often associated with a poor prognosis and limited long-term survival.

How Dupixent Side Effects May Cause Blood Cancer

Researchers have proposed several theories to explain how Dupixent could contribute to the development or progression of lymphoma:

• Immune masking: Dupixent blocks IL-4 and IL-13 signaling, which normally help the body recognize abnormal T-cell growth. By silencing these inflammatory pathways, early cancer activity may go unnoticed, allowing malignant cells to multiply unchecked.
• Misdiagnosis of CTCL as eczema: The skin lesions of cutaneous T-cell lymphoma often resemble eczema. Patients prescribed Dupixent for what is believed to be eczema may actually have undiagnosed cancer, which can worsen while hidden behind anti-inflammatory treatment.
• Altered T-cell dynamics: By shifting immune balance, Dupixent may unintentionally disrupt normal T-cell surveillance, creating conditions for abnormal clones of T-cells to expand and progress into lymphoma.
• Accelerated progression: Case reports describe patients whose CTCL advanced rapidly after starting Dupixent, suggesting the drug may accelerate the course of disease in individuals with pre-existing but undetected lymphoma.

Symptoms of Dupixent-Linked Cancers

Cutaneous T-cell lymphoma (CTCL) and related cancers often mimic eczema or psoriasis, which leads to frequent misdiagnosis. Dupixent can mask these warning signs by reducing skin inflammation, allowing the disease to progress before detection.

Symptoms to monitor include:

• Persistent red, scaly patches or plaques
• Severe itching or burning that does not improve with treatment
• Thickened skin on the palms or soles
• Enlarged lymph nodes in the neck, groin, or armpits
• Widespread redness or rash covering large areas of skin
• Fatigue, night sweats, or unexplained weight loss (signs of systemic spread)

Treatment Options for CTCL and Related Lymphomas

Therapies depend on the cancer subtype and stage at diagnosis. Early detection often allows for more localized treatment, while advanced disease typically requires systemic care.

• Early-stage CTCL / Mycosis Fungoides: Topical corticosteroids, retinoids, or phototherapy with ultraviolet light.
• Advanced CTCL / Sézary Syndrome: Systemic therapies such as oral medications, chemotherapy, targeted biologics (bexarotene, interferons), or stem cell transplantation.
• Supportive care: Infection control, pain management, and interventions to improve quality of life.

Studies Link Dupixent to Cutaneous T-cell Lymphoma (CTCL)

Recent research has shown that patients treated with Dupixent (dupilumab) face a significantly higher risk of cutaneous T-cell lymphoma (CTCL). Large studies, including those in JAMA Dermatology and the European Respiratory Journal, found Dupixent users were several times more likely to develop CTCL than non-users.

Dupixent Side Effects Linked to 300% Higher Risk of CTCL

A study published in JAMA Dermatology on April 6, 2024, examined whether patients with atopic dermatitis treated with Dupixent (dupilumab) had an elevated risk of cutaneous T-cell lymphoma (CTCL).

Researchers found that Dupixent users faced a 300% higher risk of CTCL compared to non-users (OR 4.10). Even after adjusting for demographics and medication history, the risk remained more than doubled (OR 3.20).

These findings revealed a clear association between Dupixent and CTCL that could not be explained by eczema severity alone.

Dupixent Side Effects Reinforced by 350% Higher CTCL Risk

In August 2024, a TriNetX database study focused on atopic dermatitis patients to further isolate Dupixent’s risks. Researchers excluded patients with other inflammatory diseases or prior biologic use and matched participants by age, sex, and race.

The analysis showed Dupixent users faced a 350% higher risk of CTCL compared to matched controls (RR 4.59).

This reinforced the JAMA Dermatology results, providing a second, large-scale confirmation that Dupixent significantly elevates CTCL risk.

Dupixent Increased Lymphoma Risk in Asthma Patients

A June 2025 study in the European Respiratory Journal expanded the evidence beyond eczema, examining asthma patients treated with Dupixent.

• Asthma patients on Dupixent had a 4.5-fold higher risk of CTCL compared to those on ICS/LABA therapy.
• Among patients treated ≥16 weeks, the risk of mature T- and NK-cell lymphomas rose more than 14-fold.

These findings suggest Dupixent’s lymphoma risks may extend across different patient populations, not only those with eczema.

Case Reports Show Dupixent May “Unmask” Hidden Lymphomas

Concerns first emerged in 2019 case reports published in the Journal of the American Academy of Dermatology (JAAD).

Dermatologists described eczema patients later diagnosed with CTCL after starting Dupixent. In several cases, the cancer appeared to progress rapidly once Dupixent treatment began, leading physicians to warn that Dupixent’s suppression of IL-4 and IL-13 pathways may mask early lymphoma symptoms that resemble eczema, delaying proper diagnosis.

These early reports provided the first warnings of Dupixent’s cancer side effects, which were later validated by larger studies.

Safer Treatment Options Were Available

Drug manufacturers have a duty to warn when their product carries unique or heightened risks. In the case of Dupixent lymphoma side effects, patients and physicians were not told that studies were beginning to show a link to rare blood cancers such as cutaneous T-cell lymphoma (CTCL).

Other biologic therapies for eczema and asthma, including Adbry, Nucala, Fasenra, and Tezspire, were already available, and those alternatives were not associated with the same cancer concerns.

Had Sanofi and Regeneron properly disclosed the risks, doctors could have recommended different treatments, and patients could have made informed choices about their care. Instead, Dupixent was promoted as a safe long-term therapy, while emerging cancer signals were ignored. This failure to warn deprived families of the opportunity to pursue safer available options.

What to Do if You Developed Lymphoma After Using Dupixent

For years, Sanofi and Regeneron have marketed Dupixent (dupilumab) as a safe and effective treatment for eczema, asthma, and other conditions, while failing to adequately warn about the potential risk of blood cancers.

If you or a loved one have been diagnosed with cutaneous T-cell lymphoma (CTCL) or another form of T-cell lymphoma after using Dupixent, you should contact our Dupixent lymphoma lawyers for a free consultation. Our legal team can answer your questions and explain your rights to pursue compensation.

Take action to hold the manufacturers accountable for failing to disclose these serious risks and to secure the financial compensation you and your family may deserve.

CONTACT A DUPIXENT SIDE EFFECTS LAWYER