Comparative Effect of Standard Versus Extended Interval Dosing of Rituximab or Ocrelizumab in Multiple Sclerosis.

Abstract

Objective: We aimed to investigate the comparative effectiveness of standard versus personalized extended interval dosing of anti-CD20 therapy on clinical and sub-clinical outcomes in multiple sclerosis.

Methods: Clinical information was collected prospectively on Research Electronic Data Capture. Patients with age ≥ 18 years old, confirmed diagnosis of multiple sclerosis, treatment with B-cell depleting drug (Rituximab and Ocrelizumab), and minimum follow-up of 12 months with at least 3 clinical visits and at least 3 infusions of medication were included and divided into an extended interval dosing group, a standard interval dosing group, and a converters group who switched from standard to extended interval dosing. Retinal measures were obtained using spectral domain Optical Coherence Tomography. Magnetic resonance imaging acquisitions were performed in two centers using a standardized conventional imaging protocol for multiple sclerosis.

Results: Patients had a median clinical follow-up of 3.5 (0.44-7.3) years, retinal OCT follow-up of 2.6 (1.4) years, and MRI follow-up of 2.6 (1.1) years. Annualized changes in clinical measures, retinal measures, and brain volumetric measures were similar between the 3 groups. Multivariate regression analyses also showed no differences.

Interpretation: We found no differences in clinical or sub-clinical outcomes between patients treated with standard interval dosing, patients converting from standard to extended interval dosing, and patients on extended interval dosing of B-cell depleting drugs.