Klin Farmakol Farm. 2025;39(2):89-95 | DOI: 10.36290/far.2025.036

Primum non nocere: How safe is modern therapy for multiple sclerosis?

Dominika Šťastná1, 2, Dana Horáková1, 2
1 Neurologická klinika a Centrum klinických neurověd 1. LF UK a VFN v Praze
2 Registr ReMuS, ReMuS, nadační fond, Praha

Multiple sclerosis is a chronic autoimmune disease of the central nervous system which, if left untreated, leads to significant neurological disability. The early initiation of high-efficacy disease-modifying therapy has fundamentally improved patient prognosis, effectively suppressing inflammatory activity and slowing disease progression. However, higher efficacy comes with an increased risk of serious adverse events, including infections, autoimmune complications, and potentially malignancies. Infections remain the most frequent adverse event, with the risk particularly pronounced in therapies involving anti-CD20 monoclonal antibodies. This article summarises the key safety concerns associated with individual treatments and presents available preventive strategies, including vaccination, laboratory and clinical screening, dose adjustments, and immunoglobulin substitution. Real-world data play a crucial role in this context - systematic safety monitoring was launched in the Czech Republic in 2024 through the ReMuS registry, recording over 5,000 events in the first year. The article also highlights emerging therapeutic approaches with potentially more favourable safety profiles. Primum non nocere today does not mean limiting treatment but actively and individually managing risks within the framework of modern neuroimmunological care.

Keywords: multiple sclerosis, disease-modifying therapy, safety, adverse events, comorbidities.

Accepted: July 3, 2025; Published: July 4, 2025  Show citation

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Šťastná D, Horáková D. Primum non nocere: How safe is modern therapy for multiple sclerosis? Klin Farmakol Farm. 2025;39(2):89-95. doi: 10.36290/far.2025.036.
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