Mild or no COVID-19 symptoms in cladribine-treated multiple sclerosis: two cases and implications for clinical practice

De Angelis, Marcello; Petracca, Maria; Lanzillo, Roberta; Morra, Vincenzo Brescia; Moccia, Marcello

Background: The use of disease-modifying therapies (DMTs) in multiple sclerosis (MS) could affect COVID-19 outcomes by modulating the immune response, which, in turn, might favor viral replication and/or confer protection from COVID-19 induced inflammatory response Case Report: We report on two MS patients treated with cladribine, with heterogeneous demographics and clinical features, who developed mild or no symptoms from COVID-19 and produced anti-SARS-CoV-2 antibodies, notwithstanding low lymphocyte levels. Implications: Benign COVID-19 clinical course and anti-SARS-CoV-2 antibody production can occur in MS patients with lymphopenia, suggesting the possibility to respond to COVID-19 vaccination, once available, in this vulnerable population.