The FDA issued a safety warning for the MS drug Tecfidera after a patient died from a rare brain disease while taking no other medications.
The US Food and Drug Administration (FDA) issued a safety announcement about Biogen Idec’s drug Tecfidera (dimethyl fumarate). The warning came November 25, after a 54 year old female patient with multiple sclerosis (MS) developed a rare brain disorder, progressive multifocal leukoencephalopathy (PML), and died.
“Tecfidera should contact their health care professionals right away if they experience symptoms that concern them, such as new or worsening weakness; trouble using their arms or legs; or changes to thinking, eyesight, strength or balance,” read the announcement. “Health care professionals should stop Tecfidera if PML is suspected.”
The patient was not taking any other immune system drugs, or drugs thought to be associated with PML. The patient had been on a Tecfidera regimen for more than 4 years and an 18 year history with MS. The patient was being treated with Copaxone (glatiramer acetate) for 3 years prior to being enrolled in a Tecfidera trial, where she was given a placebo for 2 years. Before the patient died, she had a low number of lymphocytes in her blood, which may have contributed to a weakened immune system. However, it remains unknown if lymphocyte counts are a risk factor for PML development in Tecfidera treated or other patients.
Biogen Idec notified the FDA when the patient died. This is the FDA’s only case of PML death related to Tecfidera. PML is caused by the John Cunningham (JC) virus, which is a rare brain infection that is harmless in most people but can cause PML in patients with weakened immune systems. Symptoms of PML include weakness on one side of the body, clumsiness, vision problems, confusion, and changes in thinking, personality, memory, and orientation, but include many others, too. The progression of PML can lead to further severe disability or death.
The FDA is urging clinicians to report any side effects of taking Tecfidera to the FDA MedWatch program, via the “Contact FDA” box at the bottom of the page. Health care professionals should stop Tecfidera at the first sign or symptom suggestive of PML and perform diagnostic evaluations, including monitoring lymphocyte counts in the patients.
Typically, Tecfidera has benefitted patients with relapsing MS, when symptoms get noticeably worse. About 4,000 patients have taken Tecfidera for MS in clinical trials, including 1,000 in the last 4 years. Biogen Idec reported more than 100,000 MS patients globally have taken Tecfidera since FDA approval in 2013.