INTRODUCTION: Ofatumumab, an anti-CD20 monoclonal antibody, is a high-efficacy disease-modifying therapy for relapsing multiple sclerosis (RMS). Although pivotal trials demonstrated substantial benefits, real-world data are required to confirm treatment persistence, effectiveness, safety, and biological markers of response in routine clinical settings. This study evaluated the real-world outcomes of ofatumumab in patients treated at a specialised multiple sclerosis (MS) centre in southeastern Spain, including exploratory analyses of B cell kinetics, comorbidity burden using the Charlson Comorbidity Index (CCI), and ethnicity. METHODS: A retrospective observational study was conducted in adults with MS initiating ofatumumab between December 2022 and December 2025, with ≥ 6 months of continuous therapy. Demographic, clinical, radiological, laboratory, and pharmacological data were extracted from electronic medical records. Statistical analyses encompassed Kaplan-Meier estimates. RESULTS: B cell depletion was confirmed in all assessments. Immunoglobulin levels remained mostly stable. Ofatumumab was generally well tolerated: systemic injection-related reactions occurred in 29.9% and infections in 6.9%. Exploratory analyses showed no significant differences in relapse or magnetic resonance imaging outcomes by CCI category or ethnicity. CONCLUSION: In this Spanish real-world single-centre cohort, ofatumumab demonstrated high persistence, substantial suppression of inflammatory activity, and a favourable safety profile in routine clinical practice. Sustained B cell depletion aligned with clinical and radiological stability. These findings support the real-world effectiveness of ofatumumab across diverse patient profiles and complement evidence from pivotal trials. Further prospective studies with broader populations and longer follow-up are warranted to refine understanding of long-term outcomes and determinants of treatment response variability.
Moreno-Navarro et al. (Wed,) studied this question.