Dupixent Lawsuit [2026 Update] | T-Cell Lymphoma Claims

A Louisiana man has sued Regeneron, Sanofi-Aventis, and Genzyme, alleging Dupixent caused his previously treated cutaneous T-cell lymphoma to return, along with new tumors and other health problems.

He filed the complaint in the U.S. District Court for the District of New Jersey on August 20.

He was originally diagnosed with stage 1 CTCL in 2017 and underwent multiple treatments over the following years.

He was prescribed Dupixent for eczema in March 2025.

By October 2025, he was diagnosed with CTCL again, this time with large cell transformation and new tumors.

He stopped using Dupixent that November. He alleges that had he or his doctor known Dupixent could reignite his cancer, they would have chosen a different eczema treatment, and that the manufacturers knew about the CTCL risk but concealed it to protect profits.

He now faces lifelong medical monitoring and treatment. His suit brings claims including failure to warn, fraudulent misrepresentation, and negligent misrepresentation, seeking compensatory and punitive damages.

The case will be folded into the Dupixent CTCL MDL in the District of New Jersey, where a judge is expected to select representative bellwether cases to help gauge how juries respond to the underlying evidence before broader settlement talks.

A California woman has sued Sanofi and Regeneron, alleging her long-term Dupixent use for atopic dermatitis led to a diagnosis of mycosis fungoides, a form of cutaneous T-cell lymphoma.

Her complaint alleges that the drugmakers were aware for years of published studies linking Dupixent to an increased risk of CTCL, yet failed to update product warnings or inform treating physicians and patients of the danger.

She argues that had she known about the risk, she would have sought alternative treatment for her skin condition rather than continuing the drug long-term.

The case is the latest in a rapidly growing number of Dupixent lymphoma suits filed against the manufacturers this summer.

Several other CTCL diagnosis cases have been filed, each alleging a similar pattern: eczema patients developing lymphoma after months or years of Dupixent use.

Yet another Dupixent lawsuit has been filed against Sanofi-Aventis, Genzyme, and Regeneron in the U.S. District Court for the District of New Jersey. 

The plaintiff began Dupixent injections for atopic dermatitis in October 2023 and stopped in August 2024. She was diagnosed with mycosis fungoides, a form of CTCL, in February 2026. 

The plaintiff alleges the manufacturers knew of a causal link between Dupixent and CTCL as early as 2018, when at least 10 cases had been reported, yet never added a warning label. 

The plaintiff now requires cancer treatment, including chemotherapy and phototherapy. 

The suit brings claims of failure to warn and fraudulent misrepresentation.

The case will be consolidated into the Dupixent MDL before Judge Zahid N. Quraishi in the District of New Jersey, where bellwether trials are expected to help guide settlement talks.

Yet another plaintiff has sued Regeneron Pharmaceuticals and Sanofi-Aventis in the U.S. District Court for the District of New Jersey.

The plaintiff filed the complaint on July 10, alleging three years of Dupixent injections led to his mycosis fungoides diagnosis, a form of cutaneous T-cell lymphoma.

The plaintiff began the injections in October 2022 and developed a worsening rash by late 2025, receiving his cancer diagnosis in February 2026 after stopping the drug.

He claims the manufacturers ignored mounting scientific evidence linking Dupixent to lymphoma risk and never included any warning on the U.S. label.

The case will be consolidated into the Dupixent MDL in the District of New Jersey before Judge Zahid N. Quraishi, who is overseeing pretrial proceedings ahead of eventual bellwether trials.

An international expert consensus recommends additional screening for cutaneous T-cell lymphoma (CTCL) in patients with suspected atopic dermatitis who have unusual symptoms or whose condition fails to improve with Dupixent treatment.

The recommendations reflect growing concern that CTCL can closely resemble eczema, allowing an underlying lymphoma to go undiagnosed before treatment begins.

The expert panel advises physicians to consider skin biopsies, pathology review, and T-cell clonality testing when patients develop worsening skin disease, have adult-onset eczema without a history of atopic dermatitis, or experience symptoms that do not respond as expected to Dupixent.

The guidance also recommends avoiding Dupixent in patients with suspected or confirmed CTCL and discontinuing treatment if a CTCL diagnosis is made after therapy begins.

The recommendations add new context to the Dupixent lawsuit, which alleges some patients developed or experienced progression of cutaneous T-cell lymphoma after receiving the medication for eczema.

Although the expert consensus does not conclude that Dupixent causes CTCL, it emphasizes the importance of identifying patients whose lymphoma may have been mistaken for atopic dermatitis before treatment.

The guidance also aligns with ongoing regulatory review in the United States.

The U.S. Food and Drug Administration has identified cutaneous T-cell lymphoma as a potential safety signal associated with Dupixent and is continuing to evaluate whether additional regulatory action or labeling changes are warranted.

The federal judge overseeing the Dupixent multidistrict litigation (MDL) has scheduled the litigation’s first case management conference for October 1, 2026.

Judge Zahid N. Quraishi issued an initial procedural order setting the conference and outlining the first steps for coordinating the growing litigation in the District of New Jersey.

According to the order, the MDL currently includes 17 pending lawsuits alleging that Dupixent caused or accelerated the development of cutaneous T-cell lymphoma (CTCL).

During the conference, the court is expected to address several key organizational issues.

These include appointing plaintiffs’ leadership, establishing procedures for preserving and producing evidence, coordinating discovery, and setting a proposed schedule for pretrial proceedings.

The October hearing will determine how the consolidated litigation proceeds as additional Dupixent lawsuits continue to be transferred into the MDL.

The court’s early case management decisions will shape the timeline for discovery, motion practice, and other pretrial proceedings, while creating a uniform process for handling common factual and legal issues shared across all pending cases.

A Tennessee man has filed a Dupixent lawsuit, alleging that he developed cutaneous T-cell lymphoma (CTCL) after using the drug for approximately eight months.

According to the complaint, the plaintiff began receiving Dupixent injections in January 2025 and was diagnosed with mycosis fungoides, a subtype of CTCL, in September 2025.

The lawsuit claims that Sanofi and Regeneron failed to warn patients and physicians about the risk that Dupixent may cause or worsen certain T-cell lymphomas.

The plaintiff alleges that he started treatment the same month the FDA launched an investigation into reports linking Dupixent to CTCL diagnoses.

The complaint also points to a March 2025 federal safety report that allegedly identified an increase in cancer reports associated with the drug.

Despite those developments, the lawsuit claims the manufacturers failed to update Dupixent’s labeling to warn of CTCL risks or recommend monitoring strategies that could help detect the disease earlier.

The case has been transferred to the recently established Dupixent multidistrict litigation (MDL) in the District of New Jersey, where Judge Zahid N. Quraishi is overseeing coordinated pretrial proceedings.

The plaintiff seeks compensatory and punitive damages, asserting claims including failure to warn, design defect, negligence, negligent misrepresentation, breach of warranty, and consumer fraud.

The Dupixent litigation reached a major milestone this month after the U.S. Judicial Panel on Multidistrict Litigation approved the creation of a federal multidistrict litigation (MDL) for lawsuits alleging the blockbuster medication is linked to cutaneous T-cell lymphoma (CTCL), a rare form of non-Hodgkin lymphoma.

The decision will centralize Dupixent cancer lawsuits before a single federal judge in New Jersey, where the defendants, Sanofi and Regeneron, maintain a significant corporate presence.

The newly formed MDL is expected to immediately include approximately 20 filed cases, with many more claims anticipated as awareness of the litigation continues to grow.

Plaintiffs allege they developed CTCL after using Dupixent for conditions such as eczema and asthma, while some lawsuits have been filed by surviving family members of patients who later died from the disease.

The creation of an MDL is significant because it signals that federal courts recognize the growing number of cases raising similar factual and scientific questions.

Centralized proceedings will allow the parties to conduct coordinated discovery regarding what the manufacturers knew about the potential cancer risks, when they became aware of those concerns, and whether stronger warnings should have been provided to physicians and patients.

The litigation has also drawn attention to research published in recent years suggesting a potential association between Dupixent use and CTCL diagnoses.

Plaintiffs contend that the manufacturers failed to adequately warn consumers about the possibility that the drug could trigger, accelerate, or unmask the rare lymphoma. Notably, Dupixent’s current prescribing information does not contain a warning regarding CTCL risk.

With the MDL now established, the litigation is expected to move into a critical discovery phase that could shape future bellwether trials and potential settlement discussions.

As additional claims are filed nationwide, the proceedings will likely become the focal point for evaluating whether Dupixent’s benefits were marketed without adequate disclosure of potential cancer-related risks.

The Dupixent litigation continues to expand as plaintiffs allege the blockbuster eczema drug may trigger, accelerate, or mask symptoms of cutaneous T-cell lymphoma (CTCL), a rare form of non-Hodgkin’s lymphoma.

In a newly filed lawsuit, a Delaware woman claims Dupixent manufacturers Regeneron and Sanofi failed to adequately warn patients and physicians about the potential cancer risks, despite growing evidence linking the drug to CTCL diagnoses and disease progression.

The complaint cites a growing body of medical literature, adverse event reports, and physician observations suggesting that some patients treated for eczema were later diagnosed with CTCL after beginning Dupixent therapy.

Plaintiffs allege the drug may delay recognition of underlying lymphoma because early CTCL symptoms often resemble eczema, potentially allowing the disease to progress before a proper diagnosis is made.

The case comes as the Judicial Panel on Multidistrict Litigation considers whether to consolidate all federal Dupixent cancer lawsuits into a single MDL for coordinated proceedings.

If centralized, the litigation could move toward bellwether trials focused on allegations that the manufacturers knew or should have known about the potential lymphoma risks but failed to provide adequate warnings to physicians and patients.

A new product liability lawsuit filed in federal court alleges that the manufacturers of Dupixent failed to adequately warn doctors and patients about a potential link between the medication and certain forms of T-cell lymphoma, including cutaneous T-cell lymphoma (CTCL).

The complaint was filed on May 5, 2026, in the U.S. District Court for the Northern District of Illinois by plaintiff Charity Njambi Kamoche against Regeneron Pharmaceuticals, Sanofi, and Genzyme.

According to the lawsuit, the manufacturers knew or should have known that Dupixent may increase the risk of developing CTCL or accelerate the progression of undiagnosed lymphoma cases.

Dupixent received approval from the U.S. Food and Drug Administration in 2017 as a treatment for atopic dermatitis, commonly known as eczema.

The drug later received additional approvals for asthma, chronic obstructive pulmonary disease (COPD), and other inflammatory conditions.

Dupixent became one of the highest-selling biologic medications in the United States as prescribing expanded across multiple chronic diseases.

According to reports discussing the litigation, a panel of federal judges is expected to hear arguments later this month regarding whether Dupixent CTCL Lawsuits filed across the country should be consolidated into multidistrict litigation (MDL).

Multidistrict litigation is a federal procedure that centralizes similar lawsuits before one judge to streamline pretrial proceedings, discovery, and evidentiary rulings.

A federal judicial panel will consider whether to consolidate pending Dupixent Lawsuits into a multidistrict litigation (MDL) following growing claims that the drug may be linked to certain cancer risks.

A report states that oral arguments are scheduled for next month on whether Dupixent cancer lawsuits should be centralized before a single federal judge for coordinated pretrial proceedings.

The pending Dupixent Lawsuits involve claims that the drug may increase the risk of cutaneous T-cell lymphoma and peripheral T-cell lymphoma. Plaintiffs allege that emerging research has identified potential links between immune modulation from Dupixent and the development or progression of lymphoma and other cancer types.

If the federal panel approves consolidation, all Dupixent Lawsuits would be transferred to a single court for coordinated discovery and pretrial rulings. MDL formation often leads to bellwether trials, which are early test cases selected to evaluate evidence, jury response, and potential settlement value across a larger litigation pool.

A newly filed lawsuit alleges that the eczema drug Dupixent is associated with the development of peripheral T cell lymphoma and resulted in a patient’s death, marking one of the first wrongful death claims involving this medication.

According to the complaint, the patient was prescribed Dupixent for treatment of eczema and was later diagnosed with peripheral T cell lymphoma after beginning the injections.

The lawsuit claims that the drug either caused or accelerated the progression of the cancer and that the manufacturers failed to provide adequate warnings about this potential risk.

The case further alleges that symptoms of lymphoma may have been misinterpreted as worsening eczema, delaying proper diagnosis and treatment.

The litigation adds to the growing number of claims involving Dupixent and T-cell lymphomas, including both cutaneous and peripheral forms.

Plaintiffs generally argue that the drug’s mechanism of action, which alters immune signaling, may contribute to the development or progression of these cancers.

Federal regulators have identified lymphoma as a potential safety signal in connection with Dupixent, but no causal relationship has been definitively established.

The medication remains widely prescribed for conditions such as eczema, asthma, and chronic sinusitis, and ongoing research continues to evaluate its long term safety profile.

The case is in its early stages, and no rulings or settlements have been reported.

Additional lawsuits are expected as attorneys continue to investigate similar claims nationwide

A Pennsylvania man filed a product liability lawsuit against Dupixent manufacturers Regeneron Pharmaceuticals Inc. and Sanofi-Aventis U.S. LLC on March 25, 2026, in the U.S. District Court for the Eastern District of Pennsylvania.

William Hinton Jr. and his wife, Labarbara, allege the companies failed to warn about the risk of T-cell lymphoma associated with Dupixent (dupilumab), despite knowing of the risks as early as 2018.

Hinton’s complaint states he received Dupixent injections from April 2025 to October 2025 for severe asthma and COPD.

While on the drug, a preexisting rash worsened and new rashes developed. Hinton received a CTCL diagnosis in October 2025 despite no prior history of lymphoma

Drug manufacturers Sanofi and Regeneron have agreed that lawsuits alleging a link between Dupixent and cancer should be centralized in a federal multidistrict litigation, marking a significant development in the growing number of claims involving the medication.

The litigation centers on allegations that Dupixent may be associated with cutaneous T cell lymphoma, a rare form of non Hodgkin lymphoma.

Plaintiffs claim the drug either caused the cancer, worsened undiagnosed cases, or delayed diagnosis by masking symptoms commonly associated with eczema and other skin conditions.

A motion filed in February 2026 seeks to consolidate the cases under MDL No 3180. At least fifteen lawsuits have already been identified as part of the proposed litigation.

The United States Judicial Panel on Multidistrict Litigation is expected to determine whether the cases will be centralized and where the proceedings will take place.

The Northern District of Georgia has been proposed as a potential venue, though final decisions are pending.

Both plaintiffs and defendants support consolidation, citing overlapping factual questions and the need for coordinated pretrial proceedings.

If established, the MDL would allow one federal judge to oversee discovery and early motions while preserving each plaintiff’s individual claim.

The cases remain in the early stages, and no court has determined whether Dupixent causes or contributes to cancer.

No settlements or trial outcomes have been reached.

A woman in Florida has filed a lawsuit claiming that Dupixent caused her to develop cutaneous T-cell lymphoma (CTCL) after she started treatment for atopic dermatitis.

Sandra Jaeger filed a complaint on March 4 in the U.S. District Court for the Middle District of Florida, naming Regeneron Pharmaceuticals Inc. and Sanofi-Aventis U.S. LLC as defendants.

The lawsuit alleges that the manufacturers did not adequately warn patients and doctors about the potential risk of T-cell lymphoma associated with Dupixent.

Jaeger states she started receiving Dupixent injections in February 2022 for intrinsic atopic dermatitis, with treatments given every two weeks until July 2022.

According to the complaint, she developed enlarged lymph nodes and increased white blood cell counts within a month of starting the medication, which led to her hospitalization in March 2022.

Subsequent testing and a biopsy in April 2022 confirmed lymphoma, leading to a formal diagnosis of cutaneous T-cell lymphoma in June 2022.

The lawsuit states that Jaeger stopped using Dupixent in July 2022 after another hospitalization involving pain and discoloration in her palms and feet.

She later underwent additional testing in February 2025, which led to a diagnosis of anaplastic large cell lymphoma.

Jaeger files claims for failure to warn, negligence, negligent misrepresentation, and breach of warranty, alleging that the manufacturers knew or should have known of the risk of lymphoma but failed to provide adequate warnings.

The case joins a growing number of Dupixent lawsuits alleging a link between the drug and T-cell lymphoma, as plaintiffs aim to consolidate federal claims into a multidistrict litigation.

A newly filed product liability lawsuit alleges that the eczema medication Dupixent caused a woman to develop a rare form of cancer known as mycosis fungoides, a type of cutaneous T-cell lymphoma.

Donareen Oakley and her husband filed a Dupixent lawsuit on March 3 in the U.S. District Court for the Northern District of Georgia. The lawsuit names Regeneron Pharmaceuticals Inc. and Sanofi-Aventis U.S. LLC as defendants.

Plaintiffs claim the manufacturers failed to warn patients and physicians about a potential association between Dupixent and T-cell lymphoma.

Dupixent, also known by the generic name dupilumab, received approval from the U.S. Food and Drug Administration in 2017 for the treatment of atopic dermatitis, a form of eczema.

Drug manufacturers later expanded the label to include treatment for asthma, chronic obstructive pulmonary disease (COPD), and other inflammatory respiratory and skin conditions. Expanded approvals contributed to the widespread use of the medication in the United States.

The Dupixent lawsuit states that Oakley received Dupixent injections from July 2019 through June 2020 after physicians diagnosed her with atopic dermatitis.

The complaint alleges that neither Oakley nor her prescribing physician received warnings about possible risks of cutaneous T-cell lymphoma or the importance of monitoring for symptoms associated with the disease.

Mycosis fungoides represents the most common form of cutaneous T-cell lymphoma (CTCL), a cancer affecting white blood cells that play a central role in the immune system.

A newly filed lawsuit claims that the eczema drug Dupixent may have contributed to the development of a rare and aggressive cancer, raising new questions about the medication’s long-term safety profile.

The complaint was filed in the U.S. District Court for the District of Nevada by David Luchsinger and his wife, Cheryl, against Regeneron Pharmaceuticals Inc. and Sanofi-Aventis U.S. LLC.

The lawsuit alleges that the drug manufacturers failed to warn patients and physicians that Dupixent (dupilumab) may increase the risk of T-cell lymphoma, a rare cancer affecting white blood cells that play a critical role in the immune system.

Dupixent was first approved in 2017 to treat atopic dermatitis, commonly known as eczema. It has since been prescribed for a number of inflammatory conditions, including asthma and chronic respiratory diseases, and has reportedly been used by more than one million patients worldwide.

However, emerging research has raised concerns that the drug may trigger or accelerate certain lymphomas, particularly cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL).

According to the lawsuit, Luchsinger began receiving Dupixent injections in October 2024 to treat eczema and continued treatment through March 2025.

Prior to starting the medication, he had no history of lymphoma or other related cancers.

Within months of beginning treatment, however, his eczema reportedly worsened rather than improved.

Approximately one year after starting the injections, Luchsinger was diagnosed with mycosis fungoides, a form of cutaneous T-cell lymphoma.

The lawsuit alleges that Dupixent not only contributed to the development of the cancer but also allowed the disease to progress rapidly before it was identified at a late stage.

The complaint claims that the manufacturers failed to adequately test the medication before bringing it to market and ignored growing scientific evidence suggesting a potential connection between Dupixent and T-cell lymphomas.

The lawsuit also alleges that the companies did not warn physicians that patients receiving Dupixent should be monitored for signs of lymphoma development.

The case joins a growing number of Dupixent cancer lawsuits being pursued nationwide.

Plaintiffs in these cases generally argue that drug makers knew or should have known about the potential risk of lymphoma but failed to provide sufficient warnings to the medical community and the public.

Luchsinger and his wife are seeking compensatory and punitive damages, bringing claims for failure to warn, negligence, and loss of consortium as the litigation over Dupixent’s potential cancer risks continues to develop.

Recent lawsuits involving Dupixent, a drug prescribed for atopic dermatitis and other skin conditions, allege that the medication may conceal signs of cutaneous T‑cell lymphoma (CTCL), a rare form of cancer.

Patients and their families claim that Dupixent’s effectiveness in reducing visible eczema symptoms can delay diagnosis of CTCL, potentially worsening outcomes.

Legal filings focus on whether the manufacturers, Sanofi and Regeneron, provided adequate warnings about this risk.

Attorneys highlight the so-called “masking effect,” where skin improvements may obscure underlying disease, leading to delayed biopsies and treatment.

These claims are being pursued through individual lawsuits in state and federal courts, with some attorneys seeking coordination of cases to streamline litigation.

No settlements or judgments have been reported, and the litigation is ongoing as courts continue to review allegations and potential discovery.

Health officials have updated prescribing information for Dupixent (dupilumab) to include treatment of allergic fungal rhinosinusitis (AFRS) in adults and children age 6 and older.

AFRS is a chronic inflammatory sinus condition triggered by an allergic response to fungal organisms, often causing nasal congestion, sinus pressure, polyps, and recurring infections.

Clinical data supporting the update indicate Dupixent can reduce inflammation, decrease polyp size, and lessen the need for systemic steroids or surgery in appropriate patients.

The medication’s safety profile remains consistent with prior labeling, with commonly reported side effects including injection site reactions and eye-related inflammation.

However, Dupixent is also the subject of ongoing litigation involving allegations of serious adverse effects in certain patients.

Lawsuits have raised claims that the manufacturer failed to adequately warn about potential risks and complications associated with the drug.

While the labeling update reflects regulatory recognition of Dupixent’s benefits for AFRS, the broader safety profile of the drug continues to be scrutinized in court.

Lawsuits center on whether risks were sufficiently disclosed and whether patients experienced injuries beyond what was represented in prescribing information.

Multiple federal lawsuits have been filed alleging that the drug Dupixent, used to treat eczema and other inflammatory conditions, caused patients to develop T‑cell lymphomas, including cutaneous T‑cell lymphoma.

Dupixent lawsuits claim that the manufacturers, Sanofi and Regeneron, failed to adequately warn doctors and patients about the potential cancer risks.

Plaintiffs have asked the U.S. Judicial Panel on Multidistrict Litigation to consolidate at least 15 cases into a single MDL in the Northern District of Georgia. 

Consolidation into multidistrict litigation (MDL) would centralize pretrial proceedings, reduce duplicate discovery, and address common legal and scientific questions, while each case would remain separate for individual claims.

The motion for MDL was filed in early 2026, and a decision by the panel is pending.

If approved, coordinated discovery and potential bellwether trials would move forward, shaping the resolution of these claims.

A Dupixent lawsuit filed in federal court alleges that the eczema drug caused a rare form of lymphoma and that the manufacturers failed to provide adequate safety warnings.

According to the complaint, more than 200 reports have linked Dupixent to cutaneous T-cell lymphoma (CTCL) since the medication received approval in 2017.

A report from the filed complaint states that plaintiff Michael Durkin filed the case on February 4, 2026, in the U.S. District Court for the Middle District of Florida.

The Dupixent lawsuit names Sanofi-Aventis U.S. LLC and Regeneron Pharmaceuticals Inc. as defendants.

The complaint alleges that the companies knew or should have known that Dupixent side effects included an increased risk of T-cell lymphomas, including CTCL and peripheral T-cell lymphoma (PTCL), and failed to warn patients and prescribing physicians.

The lawsuit states that more than one million patients have used Dupixent during the marketing period.

The complaint alleges that internal safety signals emerged within approximately one year of approval, including more than a dozen early reports of CTCL, which later increased to more than 200 reports by the end of 2024.

New federal lawsuits alleging that Dupixent may have caused or accelerated rare cancers like cutaneous T-cell lymphoma (CTCL) are prompting early activity in the courts, including concrete deadlines for defendants to respond.

In one of the first wrongful death cases filed in federal court, a Georgia plaintiff asserts that after being prescribed Dupixent for eczema she later developed CTCL, a rare form of non-Hodgkin lymphoma that primarily affects the skin.

The complaint alleges manufacturers Sanofi and Regeneron Pharmaceuticals failed to warn patients and doctors about this potential risk, arguably delaying proper diagnosis and treatment.

In response, judges in these early actions have moved quickly to set formal deadlines for Sanofi and Regeneron to file their initial court papers.

Those response dates require defendants to answer the complaints or challenge them with motions to dismiss by a specific date, often just weeks after service.

These deadlines signal that judges recognize the complexity of the underlying science, claims about immune-modulating drugs and cancer risk require early clarity about what facts and legal theories will be at issue.

Setting response deadlines early in the case accomplishes several things:

• It starts the clock on key procedural disputes, including motions to dismiss based on preemption, causation, and statute of limitations issues.
• It forces defendants to articulate their defense strategy sooner, rather than delaying while discovery develops.
• It helps frame the litigation schedule, including when expert reports, discovery, and later hearings might occur.

Once defendants file responses, next litigation steps generally include motions to dismiss (where manufacturers may argue plaintiffs have not stated a viable claim), early discovery disputes over medical and regulatory records, and potential coordination of multiple Dupixent cases as filings increase.

A growing body of concerns is prompting legal and medical professionals to advise patients taking Dupixent, an injectable biologic used for eczema, asthma, and related conditions, to monitor new or unusual skin lesions closely, as some reports suggest a possible association with serious skin abnormalities.

The guidance comes amid an uptick in complaints and inquiries from patients who developed persistent or concerning skin changes after initiating Dupixent, raising potential product liability and failure-to-warn issues.

While manufacturers and regulators state that clinically significant skin tumors are rare and that causation has not been established, plaintiffs’ lawyers emphasize the importance of vigilance.

They note that biologic therapies like Dupixent modulate the immune system in ways that can, in some individuals, alter skin surveillance mechanisms and potentially unmask or accelerate underlying conditions.

In the litigation context, claims may focus on whether patients and clinicians were adequately informed about plausible risks, particularly when new skin lesions arise.

Attorneys monitoring these developments are assessing whether label warnings, post-market surveillance, and risk disclosures reflect the evolving understanding of adverse events.

A newly filed Dupixent lawsuit alleges that a Georgia woman developed cutaneous T-cell lymphoma (CTCL) after approximately one year of Dupixent injections and that the manufacturers failed to warn patients and the medical community about cancer risks.

The case reflects an expanding body of litigation alleging that Dupixent’s safety profile was not properly disclosed, despite mounting reports of lymphoma among users.

Wanda Nalls filed her complaint on December 22, 2025, in the U.S. District Court for the Northern District of Georgia.

The complaint names Regeneron Pharmaceuticals Inc., Sanofi-Aventis U.S. LLC, and Genzyme Corporation as defendants.

Nalls alleges she began Dupixent treatment in August 2018 for atopic dermatitis and received injections every two to four weeks.

She reports a CTCL diagnosis in December 2018 and continued using Dupixent until August 2019.

Nalls alleges she was unaware of any connection between Dupixent and lymphoma because the manufacturers did not provide adequate warnings.

Nalls’ complaint alleges that manufacturers received multiple reports suggesting Dupixent was causing cancer before she began treatment.

The lawsuit claims that earlier warnings could have prompted physicians to monitor for symptoms or avoid prescribing Dupixent in certain cases.

The complaint states that Nalls required extensive treatment following her CTCL diagnosis, including electron beam therapy, topical medications, oral medications, and infused medications.

Nalls also alleges multiple rounds of radiation and chemotherapy, ongoing monitoring, and continuing tumor growth.

Early litigation activity in one of the first Dupixent lawsuits indicates that parties do not expect the case to reach trial until late 2027, and that broader consolidation into a federal multidistrict litigation (MDL) may follow as additional claims are filed.

Chandra Richardson filed a wrongful death Dupixent lawsuit in October 2025 in the U.S. District Court for the Middle District of Tennessee.

The complaint alleges that Cynthia Hyde developed peripheral T-cell lymphoma (PTCL) after receiving Dupixent injections for adult-onset atopic dermatitis. Hyde began Dupixent treatment in May 2024 and died in October 2024.

Richardson alleges that Dupixent manufacturers Regeneron and Sanofi-Aventis failed to adequately warn about lymphoma risks associated with the drug.

The parties were scheduled for an initial case status conference on December 9 before U.S. District Judge Eli J. Richardson and Magistrate Judge Alistair E. Newbern.

Scheduling conflicts prompted the court to reschedule the conference to December 17.

The parties previously submitted a joint proposed initial case management order on December 3 outlining their respective positions on discovery and case timing.

Richardson’s attorneys proposed simultaneous discovery on all issues, anticipating a wave of additional Dupixent lawsuits.

The filing states that the volume of claims may prompt consolidation into a federal Dupixent MDL.

Multidistrict litigation is a federal procedure that transfers similar cases filed in different districts to a single judge for coordinated pretrial proceedings, including discovery and motion practice.

Both sides agreed that the case will not be ready for trial before December 6, 2027.

The timeline reflects the complexity of scientific issues involving Dupixent and T-cell lymphoma, and the potential need for extensive expert discovery.

A federal court has set a January 7, 2026, deadline for Regeneron and Sanofi-Aventis to respond to a wrongful death lawsuit alleging that Dupixent caused a fatal T-cell lymphoma diagnosis.

The ruling marks an early procedural development in what may become broader Dupixent lymphoma litigation involving similar claims.

In early October 2025, Chandra Richardson filed a wrongful death Dupixent lawsuit in the U.S. District Court for the Middle District of Tennessee.

The complaint alleges that Cynthia Hyde developed peripheral T-cell lymphoma after receiving Dupixent injections.

Hyde was diagnosed with adult-onset atopic dermatitis in 2019 and began Dupixent treatment in May 2024. Hyde passed away in October 2024.

The lawsuit alleges that Dupixent manufacturers failed to adequately warn about the lymphoma risks associated with the drug.

On November 7, Regeneron and Sanofi-Aventis filed a motion requesting additional time to respond to the complaint.

The manufacturers stated that they received notice of the lawsuit in late October and cited the scientific and legal complexity of the allegations.

The motion requested a response deadline of January 7, 2026.

Magistrate Judge Alistair Newbern granted the request in an order issued on November 10.

The order permits the defendants to file their response by January 7, 30 days after the initial case management conference scheduled for December 8.

Judge Newbern will oversee the conference, which is expected to address scheduling matters, proposed deadlines, and early case organization.

The parties must submit a proposed initial case management order at least three business days before the conference.

Recent financial disclosures and published research have provided context for ongoing Dupixent lawsuits alleging an increased risk of lymphoma.

Company filings indicate that Dupixent sales increased more than 26 percent year over year and surpassed $15 billion in total revenue during 2024.

Dupixent remains one of Sanofi’s most profitable products following approvals across multiple inflammatory and respiratory conditions.

A study published in JAMA Dermatology in April 2024 reported that Dupixent users experienced more than a fourfold increase in the risk of developing cutaneous T-cell lymphoma compared to non-users.

Additional findings published in the European Respiratory Journal in June 2025 reported a 4.5-fold higher risk of cutaneous T-cell lymphoma among asthma patients treated with Dupixent, with the risk estimate increasing to 14-fold for patients treated for 16 weeks or longer.

Cutaneous T-cell lymphoma is a rare cancer that primarily targets the skin and affects immune cells.

Common symptoms include persistent rashes, plaques, skin discoloration, lymph node enlargement, and hair loss.

The clinical presentation often resembles that of chronic inflammatory skin disease, which may delay diagnosis.

The U.S. Food and Drug Administration’s adverse event database has received nearly 300 lymphoma reports associated with Dupixent since 2017, including more than 100 reports identifying cutaneous T-cell lymphoma.

In 2025, the Food and Drug Administration confirmed that a formal safety review is underway to determine whether labeling updates or additional warnings are warranted.

Recent medical studies have raised safety questions relevant to potential Dupixent lawsuits involving diagnoses of cutaneous T-cell lymphoma (CTCL), a rare form of skin lymphoma.

Dupixent (dupilumab), a brand-name medication, is manufactured by Sanofi and Regeneron and is prescribed for inflammatory conditions, including atopic dermatitis, asthma, and several chronic skin and immune disorders.

A study published in the Journal of the American Academy of Dermatology compared patients with atopic dermatitis who used Dupixent with those who did not receive the drug.

Researchers reported that Dupixent users experienced an approximately fourfold increase in the risk of developing CTCL.

The study did not identify an increased risk for other types of cancer. Most CTCL diagnoses occurred more than 1 year after Dupixent treatment initiation, which may be relevant to latency periods in Dupixent lawsuits.

A separate study published in Dermatologic Therapy also identified an elevated risk of CTCL among Dupixent users.

Researchers reported that the risk appeared highest in the first year of treatment and was more pronounced among patients aged 60 and older.

Both studies used observational data and did not establish a definitive causal relationship, though the findings have prompted increased scrutiny of Dupixent’s long-term safety profile.

Regulatory data also contributes to ongoing evaluations of the safety of Dupixent.

According to the U.S. Food and Drug Administration’s Adverse Event Reporting System, tens of thousands of adverse events associated with dupilumab have been reported in 2025, including reports referencing CTCL. FAERS data relies on voluntary submissions and does not establish causation.

The U.S. Food and Drug Administration placed Dupixent on a safety watch list for potential regulatory action in late 2024, and no public update has been issued as of August 2025.