Humoral immune response and safety of Sars-Cov-2 vaccine in people with multiple sclerosis.

Background: For the past three years, the pandemic has had a major effect on global public health, mainly on those with underlying medical conditions, such as people living with Multiple Sclerosis. Vaccination among this group is of great importance, and the long-term impacts of vaccination and its safety on the health of these patients will continue to be revealed. Therefore, risks related to vaccination and immune response need to be assessed. The objective here was to characterize the immune response, short-term safety, and the effects of multiple variables on these factors after COVID-19 vaccination (mainly Sinopharm) among people with Multiple Sclerosis. We assessed the short-term safety and humoral SARS-COV-2 anti-RBD IgG response using a data collection form and Immunoassay, respectively.

Results: No severe adverse events or MS relapse was observed. Myalgia/body pain (26.7%), low-grade fever (22.2%), and mild headache (15.6%) were the most common adverse events. The use and type of vaccine influenced the frequency of side effects with a p-value < 0.0001. Regarding immune response, patients on rituximab and fingolimod had a lower antibody titer compared to other medications. With a significant difference, hybrid immunity (p-value: 0.047) and type of DMTs (p-value: 0.017) affected the humoral response.

Conclusion: There is a low incidence of serious adverse effects, MS worsening or relapse after COVID-19 vaccination, and mainly, side effects are similar to that of the general population. It appears that treatment with various disease-modifying therapies does not induce or worsen the post-vaccination side effects, although some, including Rituximab and fingolimod, may affect the immunity induced after vaccination.