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The monitoring requirements and discontinuation criteria for dimethyl fumarate (Tecfidera) have been strengthened following a small number of reports of progressive multifocal leukoencephalopathy (PML) in patients with mild lymphopenia. Continue to monitor lymphocyte counts and advise patients to seek urgent...
Check full blood counts before prescribing dimethyl fumarate and then every 6 to 12 months. Stop treatment immediately if you suspect progressive multifocal leukoencephalopathy.
Cases of progressive multifocal leukoencephalopathy have been reported in patients taking dimethyl fumarate for multiple sclerosis, who all had prolonged lymphopenia.
A summary of letters and drug alerts recently sent to healthcare professionals.
In November, letters were sent regarding thalidomide, mycophenolate mofetil, nicorandil, InductOs, and dimethyl fumarate
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