Evaluation of the humoral response during ocrelizumab therapy in multiple sclerosis - an observational study.

INTRODUCTION

Anti-CD20 monoclonal antibodies are widely used as high-efficacy treatment agents (HETAs) in multiple sclerosis (MS). In patients treated with ocrelizumab (OCR), reduced serum IgG levels are a common laboratory abnormality. Infections are among the most frequently observed adverse events during OCR therapy.

MATERIAL AND

METHODS

We analyzed the humoral immune response during OCR therapy in 52 people with multiple sclerosis (PwMS) and assessed the safety of this treatment, including treatment-related adverse events and infection rates over a period of up to six years.

RESULTS

After three years of treatment, immunoglobulin G (IgG) and IgG1 levels decreased, particularly in the relapsing-remitting MS (RMS) group. Higher body mass index (BMI) was associated with lower Ig levels and greater CD19+ cell depletion. Infections were more frequent in patients with relapses within 3 months prior to OCR initiation. Clinical implications/future directions. Ocrelizumab treatment for up to six years showed a manageable safety profile. Given the higher infection risk in patients with greater disease activity, earlier HETA initiation may be beneficial. The association between higher BMI and CD19+ cell depletion warrants further study to support personalized OCR dosing strategies.