ABSTRACT
OBJECTIVE: To estimate the risk of progressive multifocal leukoencephalopathy (PML) and the safety of natalizumab administration in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: A descriptive retrospective observational study including all patients with RRMS treated with natalizumab followed-up after 10 years.The likelihood of developing PML was estimated based on three risk factors: anti-John Cunningham virus antibody index, previous immunosuppressive therapy, and duration of treatment. Patients were classified into five categories: minimum probability (<0.1/1000); low (0.1/1000); medium-low (0.2-0.6/1000); medium-high (0.8-3/1000); high probability (3-10/1000). RESULTS: 34 patients were included. The probability of PML in the last cycle was: 55.9% minimum, 8.8% low, 11.8% medium-low, 3% medium-high, and 20.5% high. 12 patients continue with active treatment with natalizumab. No cases of PML have been confirmed. Adverse effects were detected in 50% of patients. CONCLUSIONS: Quantifying risk factors allows us to estimate the probability of PML appearance, thus assessing the maintenance or suspension of natalizumab.
Subject(s)
Leukoencephalopathy, Progressive Multifocal , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Humans , Leukoencephalopathy, Progressive Multifocal/chemically induced , Leukoencephalopathy, Progressive Multifocal/diagnosis , Leukoencephalopathy, Progressive Multifocal/epidemiology , Multiple Sclerosis/chemically induced , Multiple Sclerosis/complications , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Natalizumab/adverse effects , Retrospective StudiesABSTRACT
BACKGROUND: Disease-modifying therapies for multiple sclerosis have been developed tremendously over the last two decades. OBJECTIVE: The aim of this study was to review the short-, medium-, and long-term safety of alemtuzumab in relapsing remitting multiple sclerosis (RRMS). METHOD: This retrospective observational study (2015-2019) included all patients with highly active or rapidly progressing and aggressive RRMS who were treated with alemtuzumab at the Cabueñes University Hospital. The short-, medium-, and long-term adverse effects were evaluated following the risk management program of the European Medicines Agency. RESULTS: 39 patients were included, 23 of them received at least two cycles of treatment. Most patients showed at least one adverse event. The following adverse reactions were reported: infusional reactions (17), urinary tract infections (six), thrombopenia (five), and thyroid dysfunction (six). CONCLUSION: In clinical practice alemtuzumab showed an acceptable safety profile in selected patients even if all of them suffered at least one adverse effect. Thorough and prolonged follow-up is required to further confirm the safety of this drug.
