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Multiple Sclerosis – PML Risk — SCE Neurology MCQ

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HardMultiple Sclerosis & CNS InflammationMultiple Sclerosis – PML RiskSCE Neurology

A 35-year-old woman with RRMS has been on natalizumab for 3 years. Her JCV antibody index has risen to 2.5. She has had no relapses on treatment. What is the most appropriate management?

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Correct answer: A — Switch to an alternative high-efficacy DMT such as ocrelizumab

A JCV antibody index >1.5 in a patient on natalizumab for >2 years confers a high risk of progressive multifocal leukoencephalopathy (PML). Current guidance recommends switching to an alternative high-efficacy DMT. Ocrelizumab is a commonly chosen alternative. The washout period should be minimised to reduce rebound disease activity. A: Extended-interval dosing reduces but does not eliminate PML risk sufficiently at this index level. C: Stopping without alternative therapy risks severe rebound. D: MRI surveillance alone is insufficient given the high risk. E: Glatiramer acetate is a moderate-efficacy agent, inadequate for this patient's needs.

Reference: ABN MS Guidelines (2022); NICE TA127/TA1126 Natalizumab; AAN Practice Guideline MS DMTs (2018)