Dupixent Mycosis Fungoides Lawsuit Filed Over Failure To Warn About T-Cell Lymphoma Risks

Woman says she developed the most common form of CTCL, mycosis fungoides, which is incurable and fatal if not caught before advanced stages.

A newly filed product liability lawsuit claims that repeated injections of Dupixent lead to the development of a form of T-cell lymphoma known as mycosis fungoides, which starts as rashes on the skin, but could spread to the lymph nodes and other organs.

Donareen Oakley, and her husband Claude, brought the complaint (PDF) in the U.S. District Court for the Northern District of Georgia on March 3, naming Regeneron Pharmaceuticals Inc. and Sanofi-Aventis U.S. LLC, as defendants.

Dupixent (dupilumab) is an injected medication originally used to treat atopic dermatitis, a form of eczema. Approved in 2017, the label was later expanded to include asthma, chronic obstructive pulmonary disease (COPD) and other inflammation-based respiratory tract and skin conditions.

Dupixent Mycosis Fungoides Risks

While the medication has been marketed as safe and effective by its manufacturers, Dupixent side effects have been linked to T-cell lymphoma, a rare form of cancer that impacts the body’s white blood cells, which are a key part of the immune system. These concerns have raised warnings that the medication may increase the risk of cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL).

Mycosis fungoides is the most common type of CTCL. It causes red scaly patches on the skin that itch, and could be confused with eczema or psoriasis, making it potentially harder to detect in patients already diagnosed with atopic dermatitis. 

While incurable, it usually progresses slowly and most patients diagnosed with it do not die from the disease. However, in later stages, like most forms of cancer, it can become far more dangerous if it spreads to the lymph nodes and other organs. At that point, five-year survival chances plummet. Fortunately, this seems to only occur in about 10% of cases of late diagnosis.

Amid the rising CTCL risks, the Oakleys’ complaint joins a growing number of similar Dupixent lawsuits being filed in courts nationwide. Each raises allegations that the drug’s manufacturers knew, or should have known, that Dupixent may increase the risk of mycosis fungoides and other forms of CTCL and PTCL, yet failed to adequately warn patients or the medical community while continuing to market the treatment.

According to the lawsuit, Oakley developed a skin rash that was diagnosed as atopic dermatitis, and received Dupixent injections from July 2019 until about June 2020. She alleges that neither she nor her physician were warned that the drug carried any potential cancer risks.

Although the treatment initially appeared to improve her condition, the complaint states that Oakley soon developed new spots and worsening rashes. In August 2020, she was diagnosed with mycosis fungoides.

Since the diagnosis, Oakley has undergone UVB light therapy and Kenalog injections, and continues to use topical corticosteroids and methotrexate as part of her treatment.

The lawsuit alleges that the manufacturers concealed evidence linking Dupixent to cancer risks from the public, the medical community and regulators.

“At the time that Plaintiff was first prescribed Dupixent, Defendants were or should have been on notice that there existed reasonable evidence of a causal association between Dupixent and development and/or progression of CTCL.”

– Donareen Oakley et al v. Regeneron Pharmaceuticals et al

Oakley says that she will continue to suffer from mycosis fungoides side effects for the rest of her life. The couple presents claims of failure to warn, and negligence. They seek both compensatory and punitive damages.

Dupixent Mycosis Fungoides Lawsuits

Last month, several plaintiffs filed a petition calling for all federally filed claims to be consolidated before one U.S. District Judge in the Northern District of Georgia to form a Dupixent lawsuit multidistrict litigation (MDL). If this MDL is established, the Oakleys’ lawsuit and similar claims will be included for coordinated discovery and pretrial proceedings.

Centralization could lead to early bellwether trials, designed to gauge how juries may respond to evidence and testimony likely to be repeated throughout the litigation. However, each case would remain an individual lawsuit, and plaintiffs would retain their own counsel to prove that their injuries were directly caused by the medication’s side effects.

Dupixent lawyers provide no-cost consultations to review medical records, discuss possible claims and determine whether individuals may be eligible for a Dupixent lawsuit settlement. These claims are handled on a contingency basis, meaning there are no upfront legal costs and attorney fees are only paid if a settlement or verdict is obtained.