COVID-19 Vaccination Reactogenicity in Persons With Multiple Sclerosis

Area of Science:

• Neurology
• Immunology
• Vaccinology

Background:

• Limited data exist on SARS-CoV-2 vaccine reactogenicity in people with multiple sclerosis (PwMS).
• Understanding vaccine safety in PwMS, especially concerning disease-modifying therapies (DMTs), is crucial for informed decision-making and addressing vaccine hesitancy.

Purpose of the Study:

• To assess SARS-CoV-2 vaccine reactogenicity in PwMS.
• To investigate the influence of various DMTs on vaccine reactions.
• To provide real-world safety data for vaccine-hesitant PwMS.

Main Methods:

• A retrospective cross-sectional study using data from the iConquerMS online research network.
• Participants reported local and systemic reactions within 24 hours of SARS-CoV-2 vaccination.
• Multivariable models analyzed associations between clinical factors, DMT use, and vaccine reactogenicity.

Main Results:

• 64% of 719 PwMS reported reactions after the first dose; 17% reported severe reactions. Common reactions included injection site pain, fatigue, and headache.
• Second vaccine doses in 442 PwMS showed similar reaction profiles, with 74% reporting reactions and 22% reporting severe reactions.
• Younger age, female sex, prior infection, and specific vaccines (Oxford-AstraZeneca, Moderna) were associated with increased reactogenicity. Certain DMTs (alpha4-integrin blockers, S1P receptor modulators, fumarates) were linked to lower reactogenicity.

Conclusions:

• SARS-CoV-2 vaccine reactogenicity in PwMS is comparable to the general population.
• Specific DMTs may reduce vaccine reactions in PwMS.
• Short-term vaccine reactions were generally self-limiting.