Objective: to evaluate the efficacy and safety of divozilimab, a humanised anti-CD20 monoclonal antibody, in patients with relapsing-remitting multiple sclerosis (MS) in real-world clinical practice.

   Material and methods. Divozilimab therapy was administered to 26 patients with MS. The observation period from the start of therapy was 5–7 months. The efficacy of therapy was assessed according to NEDA-3 criteria. As an additional laboratory indicator, the number of CD19+ and CD27+ cells was assessed in 10 patients by flow-cytometric immunophenotyping of peripheral blood lymphocytes. Safety monitoring consisted of assessing the frequency, severity and seriousness of adverse events (AEs) and the dynamics of laboratory parameters.

   Results. During the year prior to the start of divozilimab therapy, 24 out of 26 patients (92.3 %) experienced at least one clinical exacerbation, with some patients experiencing up to two or three exacerbations during the year. The median number of contrast-enhancing lesions on MRI was two. During the 5–7 months of therapy, there were no clinical exacerbations, progression of disability, or appearance of active lesions on MRI, indicating that all patients achieved NEDA-3 status. During treatment, three cases (5.8%) experienced mild infusion reactions. Two patients (7.7 %) subsequently experienced mild to moderate adverse events, which did not require discontinuation of therapy. None of the patients who underwent lymphocyte immunophenotyping had CD19+ and CD27+ cells (0 cells/μl).

   Conclusion. Short-term therapy with divozilimab demonstrated a favourable safety profile and efficacy according to NEDA-3 criteria. The absence of repopulation of CD19+, CD27+ cells indicates the efficacy of divozilimab B-cell lymphodepletion. Good tolerability and convenient administration underscore divozilimab application value in clinical practice. Longer follow-up and comparative studies with larger samples are needed to further investigate the safety and efficacy of its use.