Answer
PML is a rare JC-virus brain infection that can cause severe disability or death. Risk has been reported with dimethyl fumarate even during mild lymphopenia.
Sources for this answer
- Dimethyl Fumarate Mylan 120 mg Gastro-resistant Hard Capsules — Current selected SmPCemc · Summary of Product Characteristics
- UK GovernmentUK Government · Reputable Web
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