Siponimod following Alemtuzumab in secondary progressive MS: investigating sequential therapy-A case series.

Alemtuzumab, a humanized anti-CD52 monoclonal antibody, is approved for treatment of highly active relapsing multiple sclerosis (MS) but requires vigilant post-treatment monitoring due to associated risks. The prescription of subsequent therapies following Alemtuzumab, as mandated by label guidance for a treatment-free period of at least 5 years, presents a complex challenge, particularly if there is concurrent conversion to secondary progressive disease course. We described a case-series of five patients starting therapy with Siponimod and followed up for 12 months period converted to secondary progressive MS previously exposed to Alemtuzumab. All patients received Siponimod 2 mg. Clinical evaluation measured with Expanded Disability Status Scale and cognitive evaluation measured with Brief International Cognitive Assessment for Multiple Sclerosis were stable after 12 months on therapy. No severe lymphopenia was recorded, nor serious adverse events. In conclusion, the long-term management of patients treated with Alemtuzumab transitioning to secondary progressive MS requires a proactive and multidisciplinary approach. By addressing the challenges associated with treatment limitations and short-term monitoring recommendations while considering alternative therapeutic options like Siponimod, clinicians can optimize outcomes and ensure continuity of care for individuals with MS.