Vaccinations in multiple sclerosis patients receiving disease-modifying drugs

Purpose of review This review focuses on new evidence supporting the global immunization strategy for multiple sclerosis (MS) patients receiving disease-modifying drugs (DMDs), including the recently available vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Recent findings New data strengthen the evidence against a causal link between MS and vaccination. Recent consensus statements agree on the need to start vaccination early. Timings for vaccine administration should be adjusted to ensure safety and optimize vaccine responses, given the potential interference of DMDs. Patients treated with Ocrelizumab (and potentially other B-cell depleting therapies) are at risk of diminished immunogenicity to vaccines. This has relevant implications for the upcoming vaccination against SARS-CoV-2. An early assessment and immunization of MS patients allows optimizing vaccine responses and avoiding potential interference with treatment plans. Vaccinations are safe and effective but some specific considerations should be followed when vaccinating before, during, and after receiving immunotherapy. A time-window for vaccination taking into account the kinetics of B cell repopulation could potentially improve vaccine responses. Further understanding of SARS-CoV-2 vaccine response dynamics in MS patients under specific therapies will be key for defining the best vaccination strategy.