Breakthrough SARS-CoV-2 infections after COVID-19 mRNA vaccination in MS patients on disease modifying therapies during the Delta and the Omicron waves in Italy

CD19+ B cell numbers predict the increase of anti-SARS CoV2 antibodies in fingolimod-treated and COVID-19-vaccinated patients with multiple sclerosis

“…The only lymphocyte class significantly associated with a higher increase in the antibody level at multivariable analysis was the level of CD19+ lymphocytes (absolute number and percentage) (Figure 1), with an average 19% increase in antibody levels for each additional percentage increase in CD19+ lymphocytes (Table 1A) and an average 1% increase in antibody levels for each additional number/mm 3 of CD19+ lymphocyte (Table 1B). For both analysis increasing age was significantly associated to a lower level of antibodies.…”

Response to COVID-19 booster vaccinations in seronegative people with multiple sclerosis

“…T-cell and antibody testing of pwMS on certain DMTs may allow more individualised counselling on infection risk. Those with detectable IgG antibodies against the spike protein are likely to have greater clinical protection that those with borderline or absent responses; breakthrough infections have been linked to antibody titre in an Italian cohort ( Sormani et al, 2022 May 5 ). This highlights the importance of ensuring full vaccination prior to treatment initiation with fingolimod and anti-CD20 monoclonal antibodies in particular.…”

Humoral response to COVID-19 vaccination in MS patients on disease modifying therapy: Immune profiles and clinical outcomes

“…Recent data indicate that COVID-19 breakthrough infection strongly correlates with SARS-CoV-2 antibody level. ( Sormani et al, 2022 ) Thus, we suggest that individualized dosing and consideration of extended interval dosing with monitoring of B-cell counts may be safe ( Rolfes et al, 2021 ) and of benefit to some patients to allow for B-cell reconstitution and humoral response to vaccination in vaccine non-responders.…”

“…Recent work has shown a significant correlation between breakthrough COVID-19 infection and SARS-CoV-2 spike antibody level ( Sormani et al, 2022 ), indicating spike antibody level (i.e. humoral vaccination response) may represent some level of protection from clinical COVID-19.…”