Anat Achiron, MD, PhD, Sheba Medical Center and Tel-Aviv University, Tel Aviv, Israel, outlines the findings of an observational study investigating the immune response to COVID-19 vaccination in patients with multiple sclerosis (MS). The study investigated successful mounting of a humoral post-vaccination SARS-CoV2 IgG response and cellular immune response, assessed by memory B-cells specific for SARS-CoV-2 receptor-binding domain (RBD) and memory T-cells responsive to SARS-CoV2, as well as factors contributing to these responses. Data analysis demonstrated that in patients with MS, humoral and cellular responses were comparable to healthy subjects. However, patients treated with fingolimod or ocrelizumab showed a significantly decreased immune response. Prof. Achiron discusses the implications of these observations and how fingolimod- and ocrelizumab-treated patients should be managed. This interview took place at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) congress 2021.