Natalizumab-associated progressive multifocal leukoencephalopathy in patients with multiple sclerosis: risk reduction, management and possibilities for subsequent immunoregulation

Abstract

The risk of progressive multifocal leukoencephalopathy (PML) is one of the factors limiting the widespread use of natalizumab (NTZ). As a strategy for potentially reducing the frequency of the NTZ-associated PML, while maintaining the high therapy efficacy, in addition to the widely-used risk stratification strategy based on anti-JC virus antibody index and therapy duration, we propose the administration of NTZ with an extended dosing interval. Opinions vary on the effectiveness of plasmapharesis in confirmed cases of PML. The most challenging problem is how to manage patients, who develop PML, and what MS disease-modifying therapy should be considered for the subsequent use.

Keywords

• multiple sclerosis
• natalizumab
• progressive multifocal leukoencephalopathy
• plasmapheresis
• extended dosing intervals