Intrathecal treatment trial of rituximab in progressive MS: An open-label phase 1b study.

OBJECTIVES: To perform a phase 1b assessment of the safety and feasibility of intrathecally delivered rituximab as a treatment for progressive multiple sclerosis (PMS) and to evaluate the effect of treatment on disability and CSF biomarkers during a 1-year follow-up period.

METHODS: Three doses of rituximab (25 mg with a 1-week interval) were administered in 23 patients with PMS via a ventricular catheter inserted into the right frontal horn and connected to a subcutaneous Ommaya reservoir. Follow-ups were performed at 1, 3, 6, 9, and 12 months.

RESULTS: Mild to moderate vertigo and nausea were common but temporary adverse events associated with intrathecal rituximab infusion, which was otherwise well tolerated. The only severe adverse event was a case of low-virulent bacterial meningitis that was treated effectively. Of 7 clinical assessments, only 1 showed statistically significant improvement 1 year after treatment. No treatment effect was observed during the follow-up period among 6 CSF biomarkers.

CONCLUSIONS: Intrathecal administration of rituximab was well tolerated. However, it may involve a risk for injection-related infections. The lack of a control group precludes conclusions being drawn regarding treatment efficacy.

CLINICALTRIALSGOV IDENTIFIER: NCT01719159.

CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that intrathecal rituximab treatment is well tolerated and feasible in PMS but involves a risk of severe infections.