Expanding the indications of cladribine tablets for multiple sclerosis: From early use in treatment-naive patients to the possibility of retreatment courses after 4 years of cladribine initiation therapy

Autoimmune disorders are common clinical conditions that result from an abnormal immune response to the body’s own structures. Most existing immunomodulatory drugs for multiple sclerosis (MS) therapy are capable of suppressing autoimmune reactions as long as they are used, but they do not target autoreactive immunological memory and cannot disable the underlying mechanisms to induce remission without therapy. Over the past decade, there has been an increased interest in highly effective immune reconstruction therapy (IRT), which can transiently or persistently provoke the immune system resetting. Cladribine (2-chloro-deoxyadenosine) in tablets belongs to the group of IRT drugs for relapsing multiple sclerosis (RMS), which therapy consists of two short courses of treatment during the 1st and 2nd year. Most patients achieve sustained efficacy with the use of cladribine, but a small proportion of patients may experience new disease activity that requires the treating physician to make a decision regarding a previously chosen treatment strategy. Since cladribine tablets were approved by the European Union, USA and Russia more than 5 years ago, the number of publications devoted to the analysis of real-world practice has been steadily increasing. The purpose of this publication is to present the results of Expert Council conducted in February 2026. The participants of the expert council developed further recommendations for the administration of the drug to therapeutically naive patients with relapsing-remitting MS, in secondary progressive MS with exacerbations, algorithms for managing patients with RMS with disease activity reactivation after the initial 2 courses of therapy with cladribine and subsequent follow-up, and discussed the profiles of patients in whom switching to cladribine tablets is considered as an option that reduces the risks of prolonged immunosuppression.

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