Dupixent Lawsuit for T-Cell Lymphoma Claims

Dupixent (dupilumab) is a biologic medication manufactured by Sanofi and Regeneron Pharmaceuticals that has gained widespread use since its initial FDA approval in 2017.

The drug is prescribed as monotherapy rather than a drug combination for multiple inflammatory conditions, including moderate-to-severe atopic dermatitis (eczema), asthma, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, and chronic obstructive pulmonary disease.

While Dupixent has helped millions manage debilitating inflammatory conditions, emerging evidence has revealed serious adverse effects including safety concerns about cancer risks that were not adequately disclosed to patients and healthcare providers at the time of prescribing.

How Dupixent Works in the Body

Dupixent functions as a human monoclonal antibody that fundamentally alters immune system function by targeting specific inflammatory pathways.

The given drug binds to the interleukin-4 receptor alpha (IL-4Rα) subunit, which is shared by both the IL-4 and IL-13 receptor complexes.

By blocking this receptor, Dupixent (unlike any similar drug previously approved) prevents both interleukin-4 and interleukin-13 from sending signals that trigger inflammatory responses in the body.

While this mechanism effectively reduces inflammation associated with conditions like eczema and asthma, research published in peer-reviewed journals has demonstrated that blocking IL-4 and IL-13 signaling also suppresses important immune surveillance functions.

A February 2024 study published in the PMC database noted that IL-4 and IL-13 play roles in tumor immunosurveillance, meaning these proteins help the immune system detect and eliminate abnormal cells, including cancer cells.

When Dupixent blocks these pathways, it may create conditions that allow dormant T-cell lymphomas to develop or accelerate their progression.

The drug works by preventing the dimerization (joining) of receptor subunits that would normally occur when IL-4 or IL-13 bind to their receptors.

This blocks the downstream activation of STAT6 and other signaling molecules that drive inflammatory responses.

However, this same blockade may interfere with the immune system’s ability to recognize and destroy malignant T-cells before they proliferate into lymphoma.

With over one million patients globally taking Dupixent as of 2025, including those with a condition called eosinophilia, and many remaining on the medication for years due to its intended use as a long-term treatment, the potential for cancer development creates substantial public health concerns.

Clinical trials have followed patients for up to five years of continuous Dupixent use, meaning hundreds of thousands of individuals have experienced prolonged immune suppression.

Common Conditions Treated with Dupixent

Dupixent has received FDA approval for eight distinct indications across multiple medical specialties, making it one of the most versatile biologic medications on the market.

The breadth of approved uses has contributed to its rapid adoption and widespread patient exposure.

Dupixent has received FDA approval for the following eight distinct medical conditions:

• Atopic Dermatitis (Eczema): Approved in March 2017 for moderate-to-severe atopic dermatitis and severe eczema in patients aged six months and older whose disease is not adequately controlled with topical therapies. This remains the primary indication with the highest patient volume
• Asthma: Approved in October 2018 as an add-on maintenance treatment for eosinophilic conditions including moderate-to-severe asthma with an eosinophilic phenotype or oral corticosteroid-dependent asthma
• Chronic Rhinosinusitis with Nasal Polyps (CRSwNP): Approved for adults with inadequately controlled chronic sinus inflammation accompanied by nasal polyps
• Eosinophilic Esophagitis (EoE): Approved for patients aged one year and older weighing at least 15 kg with eosinophilic inflammation of the esophagus
• Prurigo Nodularis: Approved for adults with this rare skin condition characterized by intensely itchy nodules
• Chronic Obstructive Pulmonary Disease (COPD): Approved as an add-on maintenance treatment for adults with inadequately controlled COPD experiencing worsening shortness of breath and an eosinophilic phenotype

Dupixent is prescribed across dermatology for conditions ranging from atopic dermatitis to eyelid inflammation, plus pulmonology for asthma patients, allergology, and gastroenterology practices, meaning patients diagnosed with CTCL after Dupixent use may have received the medication for any of these conditions.

The drug is typically administered as a subcutaneous Dupixent injection every two or four weeks, depending on the condition being treated and patient age.

Treatment with this given drug is intended to be long-term and continuous rather than a fixed-duration therapy.

Clinical studies have evaluated safety and efficacy for up to five years of continuous use, monitoring whether patients gain weight or develop other issues, and patients are generally maintained on the medication indefinitely as long as it remains effective.

This extended exposure period increases the cumulative risk of adverse events, including cancer development.

Real-world evidence shows that many patients remain on Dupixent for multiple years, with some studies tracking outcomes for 36 months or longer.

The prolonged immune suppression associated with years of IL-4 and IL-13 blockade may progressively increase cancer risk over time beyond common injection site reactions, particularly for rare malignancies like cutaneous T-cell lymphoma that may require extended latency periods to become clinically apparent.

If you or a loved one developed cutaneous T-cell lymphoma or another form of T-cell malignancy after taking Dupixent for any FDA-approved indication, TruLaw partners with Dupixent litigation leaders to evaluate your case and provide the legal resources necessary for pursuing compensation.

Contact TruLaw using the chat on this page to receive an instant case evaluation and determine whether you qualify to file a Dupixent Lawsuit today.

Multiple peer-reviewed studies published in 2024 and 2025 have established a statistically strong connection between Dupixent use and increased risk of cutaneous T-cell lymphoma (CTCL), a rare form of non-Hodgkin lymphoma affecting the skin.

The evidence has become sufficiently concerning that the FDA placed Dupixent on its quarterly FAERS “Potential Signals of Serious Risks/New Safety Information” list in its October-December 2024 report, published March 31, 2025, specifically identifying cutaneous T-cell lymphoma as a safety concern requiring regulatory evaluation.

This designation indicates that federal regulators have identified enough adverse event reports to warrant investigation into whether Dupixent’s labeling should be updated to warn patients and healthcare providers about this cancer risk.

What Is Cutaneous T-Cell Lymphoma (CTCL)?

Cutaneous T-cell lymphoma represents a group of rare cancers where malignant T-lymphocytes (a type of white blood cells) accumulate in the skin, causing progressive skin lesions that can eventually spread to lymph nodes and internal organs.

The disease typically begins with what appears as a mild rash with patches or plaques on the skin that may resemble eczema, psoriasis, or other common dermatological conditions, making early diagnosis challenging, particularly in patients already being treated for inflammatory skin diseases.

The National Cancer Institute provides comprehensive information about cutaneous T-cell lymphoma, a rare form of skin cancer, types and treatment approaches.

CTCL progresses through four stages based on the extent of skin involvement and whether the cancer has spread beyond the skin.

Early-stage disease (Stage I and II) affects only the skin and has a favorable prognosis, with ten-year survival rates around ninety percent.

However, advanced-stage CTCL (Stage III and IV) represents an aggressive form that involves extensive skin coverage, lymph node involvement, or spread to internal organs, with ten-year survival rates dropping to approximately fifty-three percent.

Treatment becomes more aggressive as the disease progresses and affects blood vessels, requiring combinations of chemotherapy, radiation therapy, phototherapy, and targeted immunotherapy.

Patients taking Dupixent should monitor themselves for these potential signs of cutaneous T-cell lymphoma:

• Persistent red, scaly patches or thickened plaques on the skin that do not respond to treatments for even severe eczema
• Severe itching that intensifies over time and requires medical attention when it does not respond to conventional treatments
• Changes in skin texture, color, or appearance that differ from baseline inflammatory conditions, sometimes with associated throat pain if lymph nodes are affected
• Enlarged lymph nodes, particularly in the neck, armpits, or groin areas
• Hair loss in affected skin areas requiring immediate medical care, which may occur in advanced cases

CTCL is extremely rare in the general population, affecting skin and potentially blood vessels, with an annual incidence rate of approximately six to eight cases per million people.

This rarity makes the elevated risk observed in Dupixent users particularly noteworthy from both a clinical and epidemiological perspective.

The disease disproportionately affects men and typically develops in individuals aged sixty and older, though cases can occur in younger patients.

Studies Revealing the Dupixent-CTCL Connection

A 2025 retrospective cohort study documented that Dupixent users experienced a 4.5-fold higher risk of CTCL and over 14 times higher risk of broader T-cell lymphomas compared to matched controls not exposed to the medication.

Multiple case reports have documented individual patients diagnosed with CTCL shortly after initiating Dupixent therapy, with some suggesting the drug may “unmask” dormant lymphoma or accelerate the progression of existing but undiagnosed malignancy.

The FDA’s FAERS database, which collects adverse event reports from healthcare providers, patients, and drug manufacturers, has logged more than 300 reports of lymphoma among Dupixent users as of 2025.

While not all of these reports specifically involve cutaneous T-cell lymphoma, the concerning effects Dupixent may have prompted the FDA to issue its safety signal designation in the October-December 2024 quarterly report.

The FDA’s statement that it is “evaluating the need for regulatory action” indicates the agency is determining whether Dupixent’s prescribing information should be updated with warnings, whether a black box warning is warranted, or whether other risk mitigation measures are necessary.

Researchers believe Dupixent may increase CTCL risk through its mechanism of blocking IL-4 and IL-13 signaling.

A February 2024 study published in the National Institutes of Health’s PMC database noted that IL-4 and IL-13 play important roles in tumor immunosurveillance, meaning these proteins help the immune system detect and eliminate abnormal cells, including cancer cells.

When Dupixent inhibits these pathways, it may impair the body’s natural ability to recognize and destroy malignant T-cells before they proliferate into lymphoma.

Additionally, IL-4 and IL-13 themselves have been found to be overexpressed in CTCL tumor cells, suggesting intricate interactions between these cytokines and lymphoma pathogenesis that may be disrupted by Dupixent therapy, potentially requiring patients to stop treatment.

If you developed cutaneous T-cell lymphoma after taking Dupixent for eczema, asthma, or any other condition, TruLaw partners with litigation leaders to help you understand your legal options.

Contact TruLaw using the chat on this page to receive an instant case evaluation and learn more about filing a Dupixent CTCL lawsuit.

Patients diagnosed with cutaneous T-cell lymphoma after taking Dupixent may pursue compensation through product liability lawsuits against manufacturers Sanofi and Regeneron Pharmaceuticals.

These claims allege the companies failed to adequately warn patients and healthcare providers about the CTCL risk despite evidence suggesting they knew or should have known about this danger based on the drug’s mechanism of action, clinical trial data, and post-market adverse event reports.

Filing a lawsuit does not require proving the companies intended harm, only that they breached their duty to provide adequate warnings about known or reasonably foreseeable risks associated with their product.

Clear qualification criteria help patients determine whether they may have viable legal claims against Dupixent manufacturers.

While each case requires individual evaluation based on specific health history, medical records and documentation, certain factors make claims more likely to succeed.

Patients should understand that most attorneys handling these cases work on contingency fee arrangements, meaning they receive payment only if compensation is recovered, eliminating upfront legal costs and ensuring access to justice regardless of financial circumstances.

TruLaw serves as a gateway to connecting patients with specialized Dupixent litigation attorneys through instant case evaluation via the chat feature on this page.

Eligibility Requirements for Filing a Claim

The primary requirement for filing a Dupixent CTCL lawsuit is a confirmed diagnosis of cutaneous T-cell lymphoma or related T-cell malignancy that occurred after taking Dupixent for any FDA-approved indication.

Eligible patients may have used Dupixent to treat asthma, atopic dermatitis, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, or chronic obstructive pulmonary disease.

The specific condition being treated, whether to treat eosinophilic esophagitis or another indication, does not affect eligibility, as the alleged cancer risk stems from Dupixent’s mechanism of action rather than any particular underlying disease.

To qualify for a Dupixent CTCL lawsuit, patients should provide:

• Confirmed CTCL diagnosis: Medical documentation from a dermatologist or oncologist confirming cutaneous T-cell lymphoma, typically established through skin biopsy with pathology report showing malignant T-cell infiltration
• Temporal connection to Dupixent use: CTCL diagnosis occurred during active Dupixent treatment or within a reasonable timeframe after starting the medication, recognizing that research shows most cases develop more than one year after initiation
• Treatment documentation: Prescription records, pharmacy records, or medical charts confirming Dupixent use, including dates of treatment initiation and duration of therapy
• Absence of pre-existing CTCL: The lymphoma diagnosis occurred after beginning Dupixent rather than representing progression of a condition that existed before starting the medication

This latency period after starting Dupixent treatment suggests the medication may require extended exposure to increase cancer risk or may accelerate the development of dormant malignancies that take time to become clinically apparent.

Patients diagnosed with CTCL years after beginning Dupixent therapy may still have valid claims if they can establish continuous or substantial exposure to the medication.

Medical documentation forms the foundation of any pharmaceutical injury claim.

Attorneys evaluating Dupixent CTCL cases will need complete medical records documenting both the Dupixent prescription history and the lymphoma diagnosis.

Prescription records from a licensed healthcare professional should show dates when Dupixent was prescribed, dosages, frequency of administration, and duration of treatment.

Pharmacy records confirming actual dispensing of the medication help establish exposure.

Dermatology and oncology records should include the initial observations of suspicious skin lesions (distinct from common conditions like cold sores), referrals for biopsy, pathology reports confirming CTCL diagnosis, staging information based on the extent of disease, and treatment plans implemented to address the cancer.

Statute of limitations deadlines create time constraints for filing lawsuits that vary by state.

Most states impose statutes of limitations for pharmaceutical injury cases ranging from one to six years, with the majority falling in the two-to-three-year range.

The limitations period typically begins running from the date of injury, which in CTCL cases would be the date of diagnosis rather than the date of first Dupixent use, though other factors may affect this timeline.

However, discovery rules in many states toll (pause) the limitations period until the patient knows or reasonably should have known that their injury was caused by the medication, which may extend the filing deadline for patients who only recently learned about the Dupixent-CTCL connection despite being diagnosed earlier.

TruLaw** serves as a gateway to connecting patients with specialized Dupixent litigation attorneys through instant case evaluation via the chat feature on this page.**

Contact TruLaw today to determine if you qualify to pursue compensation through a Dupixent T-cell lymphoma lawsuit.

Taking Action: Next Steps for Affected Patients

Patients who believe they developed CTCL as a result of Dupixent use should take immediate steps to preserve their legal rights and gather documentation necessary for case evaluation.

Time is of the essence, as statutes of limitations can expire and evidence may become more difficult to obtain as time passes.

Acting promptly also allows patients to potentially participate in early stages of litigation if an MDL is eventually established, which can influence settlement negotiations and trial strategies.

Patients who suspect Dupixent caused their CTCL diagnosis should take these immediate steps to protect their legal rights:

• Gather comprehensive medical records: Request complete medical records from all healthcare providers involved in Dupixent treatment and CTCL diagnosis, including prescription records from prescribing physicians noting any drug interactions, pharmacy dispensing records showing dates and quantities of medication received, dermatology records documenting skin changes and biopsy results, pathology reports confirming CTCL diagnosis and tumor characteristics, oncology records detailing cancer staging and treatment plans, and any hospital records related to cancer treatment
• Preserve prescription evidence: Locate medication bottles, prescription labels, insurance explanation of benefits statements showing Dupixent claims, or pharmacy records that can establish the duration and extent of Dupixent exposure
• Document the impact: Keep records of all cancer-related expenses including medical bills, prescription costs, travel expenses for treatment, and lost income documentation such as pay stubs or tax returns showing earning capacity before and after diagnosis

Consulting with attorneys who specialize in pharmaceutical litigation and mass tort cases is the next step after gathering preliminary documentation.

These cases examining the effects Dupixent has on patients require specific expertise in product liability law, pharmaceutical regulations, medical causation, and sophisticated litigation strategies necessary to take on well-funded corporate defendants.

Generic personal injury attorneys may lack the resources, scientific knowledge, and litigation experience needed to effectively prosecute claims against major pharmaceutical manufacturers like Sanofi and Regeneron.

Patients should understand realistic timelines for legal resolution.

Pharmaceutical product liability cases typically take one to three years to resolve through settlement or trial, though multifaceted cases may require longer.

As of October 2025, Dupixent CTCL lawsuits remain in early stages with no MDL consolidation yet established.

If case filings increase substantially, courts may consolidate claims into an MDL to streamline pretrial proceedings, conduct coordinated discovery, and resolve common legal and factual issues efficiently.

MDL consolidation can actually benefit plaintiffs by pooling resources, enabling comprehensive discovery into Sanofi and Regeneron’s conduct, and creating settlement pressure through bellwether trials.

Early-stage litigation involves extensive document production, depositions of company employees and medical experts, expert witness retention to establish causation between Dupixent and CTCL, and legal motion practice addressing liability theories and damage calculations.

Cases with clear causation evidence, well-documented Dupixent exposure, and severe damages may settle relatively quickly once defendants understand the strength of plaintiffs’ claims.

Other cases may require years of litigation and potentially trial before resolution.

TruLaw provides immediate free case review evaluations through the chat feature on this page, connecting patients with specialized Dupixent litigation partners who can assess the specific merits of each claim.

Most attorneys handling these cases offer a no obligation case review and work on contingency, meaning clients pay no fees unless compensation is recovered, typically as a percentage of any settlement or verdict.

This arrangement ensures access to high-quality legal representation regardless of a patient’s ability to pay upfront legal costs.

TruLaw** provides immediate case evaluations through the chat feature on this page, connecting patients with specialized Dupixent litigation partners who can assess the specific merits of each claim.**

Contact TruLaw today to take the first step toward holding Dupixent manufacturers accountable through a Dupixent cancer lawsuit.

Our Dupixent attorney at TruLaw is dedicated to supporting clients through the process of filing a Dupixent lawsuit.

With extensive experience in dangerous drugs cases involving reactions like unexplained weight gain, Jessica Paluch-Hoerman and our partner law firms work with litigation leaders and medical experts to prove how Dupixent medication caused you harm.

TruLaw focuses on securing compensation for medical expenses, treatment costs for side effects including serious allergic reaction, pain and suffering, lost income, and other damages resulting from your Dupixent injuries.

We understand the physical and emotional toll that Dupixent complications have on your life and provide the personalized guidance you need when seeking justice.

Meet the Lead Dupixent Attorney at TruLaw

Meet our lead Dupixent attorney:

• Jessica Paluch-Hoerman: As founder and managing attorney of TruLaw, Jessica brings her experience in product liability and personal injury to her client-centered approach by prioritizing open communication and personalized attention with her clients. Through TruLaw and partner law firms, Jessica has helped collect over $3 billion on behalf of injured individuals across all 50 states through verdicts and negotiated settlements.

How much does hiring a Dupixent lawyer from TruLaw cost?

At TruLaw, we believe financial concerns should never stand in the way of justice.

That’s why we operate on a contingency fee basis—with this approach, you only pay legal fees after you’ve been awarded compensation for your injuries, whether from cancer, trouble breathing, or other serious reactions.

If you or a loved one has suffered a severe reaction or blood cancer linked to Dupixent, you may be eligible to seek compensation.

Contact TruLaw using the chat on this page to receive an instant case evaluation and determine whether you qualify to join others in filing a Dupixent lawsuit today.

Dupixent lawsuits are being filed by individuals across the country who suffered serious side effects including joint pain and adverse reactions after taking the injectable medication for eczema, asthma, and other inflammatory conditions.

TruLaw is currently accepting clients for the Dupixent lawsuit.

A few reasons to choose TruLaw for your Dupixent lawsuit include:

• If We Don’t Win, You Don’t Pay: The Dupixent lawyers at TruLaw and our partner firms operate on a contingency fee basis, meaning we only get paid if you win.
• Expertise: We have decades of experience handling dangerous drugs cases similar to the Dupixent lawsuit.
• Successful Track Record: TruLaw and our partner law firms have helped our clients recover billions of dollars in compensation through verdicts and negotiated settlements.

If you or a loved one suffered eye complications, muscle pain, severe allergic reactions, or other serious side effects after taking Dupixent, you may be eligible to seek compensation.

Contact TruLaw using the chat on this page to receive an instant case evaluation that can determine if you qualify for the Dupixent lawsuit today, whether your case involves cancer, pink eye complications, or other serious reactions.