No evidence of fluctuations in daily step count between infusions in people with multiple sclerosis treated with anti-CD20 monoclonal antibodies.

Abstract

Background: Patients with multiple sclerosis (MS) on some disease-modifying therapies (i.e., natalizumab), report a "wearing-off" effect characterized by increased symptoms directly before infusions. Prior research suggests this may reflect natural MS fluctuations rather than true treatment waning; however, this has not been confirmed for anti-CD20 agents (e.g., ocrelizumab). Daily step count (STEPS) can reflect overall function. This study examined temporal associations between anti-CD20 therapy infusions and STEPS.

Methods: Retrospective analysis evaluated data from two Fitbit-monitored cohorts (N = 145 total, 32 anti-CD20-treated participants) across 60 treatment cycles. Monthly STEPS were recorded directly pre- and three-month post-infusion over the six-month treatment intervals. Mixed-effects models evaluated the relationship between infusion timing, STEPS, and participant demographics, controlling for confounding variables.

Results: No significant difference in STEPS was observed pre- versus post-infusion (p = 0.32). An average decrease of 3.3% was noted post-infusion but was not statistically significant. No associations between STEPS and participant characteristics (e.g., age, disability level) were identified. Individual variability existed, but no clear group-level trends emerged.

Conclusions: This study found no evidence of an association between timing of anti-CD20 infusion and changes in STEPS. Findings highlight the need for integrating objective measures with patient-reported outcomes and biomarkers in future research to better understand potential treatment fluctuations.