Rituximab in paediatric onset multiple sclerosis: a case series.

Paediatric onset multiple sclerosis (POMS) is characterized by high inflammatory activity. No disease modifying treatment has been approved for POMS. The objective of this report was to report the use of rituximab, a B cell depleting monoclonal anti-CD20-antibody, in POMS. This is a retrospective case series at four specialized MS centres in Sweden. Participants were identified through the Swedish MS-registry and our own patient stocks. Data were collected through medical charts review. We identified 14 POMS patients treated with i.v. rituximab 500-1000 mg every 6th to 12th months. Median age at disease onset was 14.7 years, median age at rituximab treatment initiation was 16.5 years, and median treatment duration was 23.6 months. No relapses were reported, and the EDSS scores remained stable or decreased in 13 of 14 cases during rituximab treatment. Beyond 6 months from initiating rituximab treatment, only one new lesion was detected on MRI. No serious AEs were reported. The drug survival was 86%. Our data indicate that rituximab treatment is safe, effective and well tolerated in children with MS. Nine POMS cases treated with rituximab have previously been published. They had higher disease activity pre-rituximab, but similar safety and efficacy outcomes after treatment. An RCT of rituximab in POMS is warranted.