ABSTRACT
BACKGROUND AND PURPOSE: Although two doses of COVID-19 vaccine elicited a protective humoral response in most persons with multiple sclerosis (pwMS), a significant group of them treated with immunosuppressive disease-modifying therapies (DMTs) showed less efficient responses. METHODS: This prospective multicenter observational study evaluates differences in immune response after a third vaccine dose in pwMS. RESULTS: Four hundred seventy-three pwMS were analyzed. Compared to untreated patients, there was a 50-fold decrease (95% confidence interval [CI] = 14.3-100.0, p < 0.001) in serum SARS-CoV-2 antibody levels in those on rituximab, a 20-fold decrease (95% CI = 8.3-50.0, p < 0.001) in those on ocrelizumab, and a 2.3-fold decrease (95% CI = 1.2-4.6, p = 0.015) in those on fingolimod. As compared to the antibody levels after the second vaccine dose, patients on the anti-CD20 drugs rituximab and ocrelizumab showed a 2.3-fold lower gain (95% CI = 1.4-3.8, p = 0.001), whereas those on fingolimod showed a 1.7-fold higher gain (95% CI = 1.1-2.7, p = 0.012), compared to patients treated with other DMTs. CONCLUSIONS: All pwMS increased their serum SARS-CoV-2 antibody levels after the third vaccine dose. The mean antibody values of patients treated with ocrelizumab/rituximab remained well below the empirical "protective threshold" for risk of infection identified in the CovaXiMS study (>659 binding antibody units/mL), whereas for patients treated with fingolimod this value was significantly closer to the cutoff.
Subject(s)
COVID-19 , Multiple Sclerosis , Humans , COVID-19 Vaccines , Antibody Formation , Fingolimod Hydrochloride , Multiple Sclerosis/drug therapy , Prospective Studies , Rituximab/therapeutic use , COVID-19/prevention & control , SARS-CoV-2 , Antibodies, Viral , VaccinationABSTRACT
BACKGROUND: Patients with multiple sclerosis (pwMS) treated with anti-CD20 or fingolimod showed a reduced humoral response to SARS-CoV-2 vaccines. OBJECTIVE: In this study we aimed to monitor the risk of breakthrough SARS-CoV-2 infection in pwMS on different disease-modifying therapies (DMTs). METHODS: Data on the number of vaccinated patients and the number of patients with a breakthrough infection were retrospectively collected in 27 Italian MS centers. We estimated the rate of breakthrough infections and of infection requiring hospitalization per DMT. RESULTS: 19,641 vaccinated pwMS were included in the database. After a median follow-up of 8 months, we observed 137 breakthrough infections. Compared with other DMTs, the rate of breakthrough infections was significantly higher on ocrelizumab (0.57% vs 2.00%, risk ratio (RR) = 3.55, 95% CI = 2.74-4.58, p < 0.001) and fingolimod (0.58% vs 1.62%, RR = 2.65, 95% CI = 1.75-4.00, p < 0.001), while there were no significant differences in any other DMT group. In the ocrelizumab group the hospitalization rate was 16.7% versus 19.4% in the pre-vaccination era (RR = 0.86, p = 0.74) and it was 3.9% in all the other DMT groups versus 11.9% in the pre-vaccination period (RR = 0.33, p = 0.02). CONCLUSIONS: The risk of breakthrough SARS-CoV-2 infections is higher in patients treated with ocrelizumab and fingolimod, and the rate of severe infections was significantly reduced in all the DMTs excluding ocrelizumab.