Mohamed Fouad Elsayed Khalil¹, Mohamed Abouelnaga², Salah Ibrahim Ahmed³, Arafa Ibrahim Mohamed Ibrahim⁴, Mohamed Elshafei⁵ and Tarek Youssif Omar Youssif⁶*

¹Department of Neurology, NMC Royal Hospital Mohamed Bin Zayed, Abu Dhabi, United Arab Emirates
²Department of Neurology, Faculty of Medicine, Alexandria University, Alexandria, Egypt
³Department of neurology, Sheikh Khalifa Medical City (SKMC), Abu Dhabi, United Arab Emirates
⁴Department of General Medicine, Madinat Zayed Hospital-ADH, SEHA Abudhabi, United Arab Emirates
⁵Department of Neurology, Zulekha Hospital Dubai, United Arab Emirates
⁶Department of Neurology, NMC Royal Hospital Khalifa City, Abu Dhabi, United Arab Emirates

*Corresponding Author: Tarek Youssif Omar Youssif, Department of Neurology, NMC Royal Hospital Khalifa City, Abu Dhabi, United Arab Emirates.

Received: October 13, 2026; Published: October 23, 2026

Abstract

Background: Anti-CD20 monoclonal antibodies are highly effective disease-modifying therapies for multiple sclerosis. Their use has expanded rapidly, making prevention and monitoring of infectious complications increasingly important in routine neurological practice.

Objective: To synthesize contemporary evidence regarding infection-risk mitigation in people with multiple sclerosis receiving rituximab, ocrelizumab, ofatumumab, or ublituximab, with emphasis on prevention, baseline assessment, vaccination, laboratory monitoring, and management of recurrent or serious infections.

Methods: We performed a systematic clinical practice review of randomized trials, extension studies, observational cohorts, registry analyses, systematic reviews, vaccine-response studies, and consensus recommendations relevant to infectious complications during anti-CD20 therapy in multiple sclerosis. Evidence was organized by infection type, hypogammaglobulinemia, vaccination response, predictors of infection, and practical management implications. Recommendations were derived from the available evidence and are presented as evidence-informed practice points rather than formal guidelines.

Results: Common infections during anti-CD20 therapy were mainly respiratory and urinary. Serious infections were uncommon in pivotal trials but became more clinically relevant in real-world cohorts, particularly among older patients, those with progressive disease, higher disability, recurrent previous infections, prolonged treatment exposure, and declining immunoglobulin concentrations. Hypogammaglobulinemia was a reproducible long-term safety signal; IgM decline was frequent, whereas persistent IgG reduction showed greater clinical relevance for serious infection risk. Vaccine-response studies demonstrated attenuated humoral responses during B-cell depletion, while cellular immune responses may be partly preserved, supporting vaccination planning before treatment initiation and individualized timing during maintenance therapy.

Conclusions: Infectious complications during anti-CD20 therapy are best approached through proactive risk mitigation rather than reactive management. Baseline infection assessment, hepatitis B screening, vaccination review, periodic immunoglobulin monitoring, patient education, and individualized management of recurrent infections should be integrated into anti-CD20 treatment pathways. Prospective studies are needed to define optimal IgG thresholds, monitoring intervals, biomarker-guided dosing strategies, and the role of immunoglobulin replacement in selected patients.

Keywords: Multiple Sclerosis; Anti-CD20; Ocrelizumab; Rituximab; Ofatumumab; Ublituximab; Infection; Hypogammaglobulinemia; Vaccination; Immunoglobulin Monitoring

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Citation

Citation: Tarek Youssif Omar Youssif., et al. “Prevention, Monitoring, and Management of Infectious Complications in People with Multiple Sclerosis Receiving Anti-CD20 Therapies: A Systematic Clinical Practice Review". Acta Scientific Neurology 9.10 (2026): 19-28.

Copyright

Copyright: ©2026 Tarek Youssif Omar Youssif., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.