COVID-19 Vaccine Antibody Responses and Infection Severity in the Setting of MS Disease Modifying Treatments

Background: Although FDA-approved COVID vaccines are safe in MS patients, the efficacy of such vaccines in the setting of DMT remains unclear. It is clear that both humoral and T-cell responses play a theoretical role in vaccine efficacy. However, the impact of DMTs on COVID vaccine antigenicity remains controversial and the impact on DMT on infection severity remains under-studied.

Objectives: The purpose of this study is to compare the immunogenicity of the COVID vaccine in MS patients treated with different classes of DMTs and the effect of these therapies on infection severity.

Methods: Serum COVID antibody data was obtained for 134 MS patients on DMT treatment following vaccination with FDA approved COVID vaccines. Anti-COVID antibodies were measured using either a immunohistochemical assay (Diasorin) or ELISA (Labcorp). COVID PCR tests were performed via nasopharyngeal swabbing. 16 patients in the study were positive for COVID-19 via PCR and disease severity data was recorded. COVID infections were categorized by severity.

Results: The prevalence of COVID antibody response was 55% in patients on anti-CD20 therapies vs 83% in patients on all other DMT (p <0.01). Patients on immunomodulators had the highest prevalence of antibody response to vaccination, with patients on teriflunomide at 91%, fumarates at 93%. In patients taking anti-CD20 therapy, antibody responses to vaccination correlated with higher baseline immunoglobulin level (p=0.01) and shorter duration of therapy. Overall, 16 patients tested positive for COVID-PCR. Most COVID infections were mild and self-limited (11/16), but 4 patients received outpatient monoclonal antibodies therapy, and one patient required hospitalization due to COVID. None of the patients required supplemental oxygenation.
Conclusions: DMTs mechanism of action appears to impact vaccination-induced antibody responses. However, COVID infections in MS patients were generally mild across DMT’s. Future studies further stratifying differences among different DMTs and response to COVID vaccination and infection are necessary.

Conclusions: DMTs mechanism of action appears to impact vaccination-induced antibody responses. However, COVID infections in MS patients were generally mild across DMT’s. Future studies further stratifying differences among different DMTs and response to COVID vaccination and infection are necessary.