Dimethyl fumarate (Tecfidera): updated advice on the risk of progressive multifocal leukoencephalopathy (PML) associated with mild lymphopenia

Monitoring requirements and discontinuation criteria have been strengthened following a small number of reports of progressive multifocal leukoencephalopathy (PML) in patients with mild lymphopenia. Lymphocyte counts should continue to be monitored and patients counselled on risk

Medicines and Healthcare products Regulatory Agency