Immunisation Status and Safety of Vaccines in Italian MS Patients

Multiple sclerosis (MS) patients are more susceptible to infections than the general population in relation to some specific therapies or increasing disability. Clearly, the use of immuno-suppressant/modulatory drugs requires particular attention to the occurrence of infectious events. In this perspective, among still unmet clinical needs in MS patients is a comprehensive picture on the immunisation status against infectious diseases, especially those preventable with vaccines. Despite of the relevance of vaccinations, there are still some concerns about their utilization in MS patients. In literature, results about their safety are conflicting or incomplete and it is yet unclear if some vaccines may trigger MS relapses. GOALS: 1) to assess immunisation status, due to past exposure to natural infectious diseases or vaccines, against major infectious agents preventable by available vaccines; 2) to assess the safety of most utilized vaccines in the clinical practice by recording relapses as adverse event in the considered risk period after vaccination. The 3-year project is conceived as a multicenter, observational, both retro- and prospective study. A cohort of about 3,000 MS subjects will be enrolled among databases of 25 clinical Centers in Italy. All patients diagnosed with relapsing remitting (RR) MS according to the 2010 Polman's criteria from 01/2011 to 12/2020 will be enrolled. Available data on natural immunisation will be collected from the historical clinical records of Centers, taking into account the presence of specific serum antibodies, whereas available data on vaccinations will be collected from vaccination records. To study the impact of vaccines on the risk of relapse, data about patients receiving a vaccination during the disease will be analysed. The study follow-up period will be between 2 and up to 6 months following vaccination: the 2-month period is considered as the maximum clinical risk, whereas 6 months as the maximal extension of risk i