Background Alemtuzumab is a humanised monoclonal antibody that selectively targets CD52, resulting in depletion and subsequent distinct repopulation of circulating T and B lymphocytes.

Purpose To evaluate the effectiveness and security of alemtuzumab in patients diagnosed with relapsing-remitting multiple sclerosis (RRMS).

Material and methods Retrospective and observational study between December 2014 and November 2017 of patients diagnosed with RRMS after 1 year of treatment with alemtuzumab.

Variables collected: age, sex, years with RRMS diagnosis, Extended Disability Status Scale (EDSS), percentage of patients without outbreaks and outbreaks/patient-year, previous treatments and adverse drug reactions (ADRs).

The effectiveness of treatment was assessed by calculating annualised relapse rates(ARRs) and change in disability status by EDSS. Change in disability was defined according to criteria of Fernández et al. that defined improvement as any decrease ≥1 point, stabilisation as any change <1 point and aggravation as an increase ≥1 point in the EDSS scale.

Results Twenty-five patients were included (72% females).

Only one patient used alemtuzumab as first line.

One-year follow-up showed EDSS improved by 0.08±0.27 point. Improved disability status was observed in two patient (one point decrease in EDDS) (8%), stabilisation in 23 patients (88%) and worsening in one patient (one point increase in EDSS) (4%).

One patient was diagnosed with Glioblastoma, so second cycle of treatment was discontinued.

Conclusion Alemtuzumab is a moderately effective drug with acceptable toxicity in patients who have failed other treatments. In Phase III clinical trials, ADRs incidence was >90%, being mild to moderate in severity and generally included headache, rash, pyrexia, nausea, flushing, urticaria, insomnia and pruritus. Also,>10% of patients showed cardiac disorders, in particular tachycardia.

References and/or Acknowledgements 1. Fernández O, et al. Natalizumab treatment of multiple sclerosis in Spain: results of an extensive observational study. J Neurol2012;259:1814–23.

2. Guarnera C, Bramanti P, Mazzon E. Alemtuzumab: a review of efficacy and risks in the treatment of relapsing remitting multiple sclerosis. Ther Clin Risk Manag2017;13:871–879.

No conflict of interest