Varying responses to the SARS-CoV-2 vaccines have been reported in pwMS on disease modifying therapies (DMTs). We performed a meta-analysis and systematic review of pwMS and rates of immune response to SARS-CoV-2 vaccines by DMT and by vaccine type.

A systematic review was conducted for manuscripts from January 1, 2019 until October 1, 2021 by two independent reviewers (M.D. and G.G.). Search terms in PubMed, Google Scholar and Embase included “multiple sclerosis,” “SARS-CoV-2”, “Coronavirus-19”, “vaccines”, and “vaccinations.” Data from publications reporting on antibody or cellular vaccine response data in pwMS were included. Antibody response was defined as positive or negative, based upon assay cutoffs. Immune response to prior COVID infections were excluded. Descriptive statistics was performed using STATA.

We included 16 out of 589 articles and 186 healthy controls and 1,239 pwMS. Protective antibody responses were detected in 99% of healthy controls (184/186), 100% untreated pwMS (169/169), 99% pwMS on beta-interferons (79/80), and 100% pwMS on glatiramer acetate (39/39), dimethyl fumarate (116/116), natalizumab (127/127), alemtuzumab (19/19), and teriflunomide (72/72). Ninety-three percent of pwMS on cladribrine (69/74), 70% of sphingosine 1-phosphate modulators (S1PM) (108/155) and forty-six percent of pwMS on anti-CD20 treatments had an antibody response (177/388). PwMS on rituximab had a higher antibody response (23/37 = 62%) as compared to ocrelizumab (107/205 = 39%), with unknown anti-CD20 in 76. This difference may be attributable to the vaccination received (mRNA-1273 vs BNT162b2) as mRNA-1273 results in higher antibodies. However, 46/49 (94%) on anti-CD20 had T cell responses to SARS-CoV-2 vaccines.

Varying rates of vaccine response are reported in pwMS. Humoral responses appear to be blunted in S1PM and anti-CD20 treatments; however, the majority develop cellular responses. Further investigation into how DMT affects immune response are needed.