Symptomatic COVID-19 course and outcomes after three mRNA vaccine doses in multiple sclerosis patients treated with high-efficacy DMTs.

BACKGROUND: Little is known about COVID-19 course and outcomes after a third booster dose of mRNA vaccine against SARS-CoV-2 (mRNA-Vax) in patients with multiple sclerosis (pwMS) treated with ocrelizumab (OCR) and fingolimod (FNG), which showed a weakened immune response to mRNA-vax. OBJECTIVES: The aim of this study was to evaluate COVID-19 course and outcomes in pwMS on OCR and FNG after receiving the third dose of mRNA-Vax and to compare it with pwMS on natalizumab (NTZ). METHODS: Inclusion criteria: >18 years of age, being treated with OCR/FNG/NTZ since the first mRNA-Vax dose; COVID-19 after a third booster dose of mRNA-Vax; no steroids use. RESULTS: Overall, 290 pwMS (79 NTZ, 126 OCR, and 85 FNG) from 17 Italian MS centers were included. Age, Expanded Disability Status Scale (EDSS) score, MS phenotype, disease, and treatment duration were significantly different across groups. PwMS who had COVID-19 on OCR and FNG compared with those on NTZ were slightly more symptomatic with higher hospitalization rates (11.1% vs 7.1% vs 1.3%, respectively). Regression models showed that the majority of the differences observed were not related to the disease-modifying treatments (DMTs) used. No fatal cases were observed. CONCLUSION: Our results support the effectiveness of the third booster dose of mRNA-Vax against severe forms of COVID-19 in pwMS treated with OCR and FNG.

Risk of Getting COVID-19 in People With Multiple Sclerosis: A Case-Control Study.

BACKGROUND AND OBJECTIVES: Several studies have assessed risk factors associated with the severity of COVID-19 outcomes in people with multiple sclerosis (PwMS). The potential role of disease-modifying therapies (DMTs) and demographic and clinical factors on the risk of acquiring SARS-CoV-2 infection has not been evaluated so far. The objective of this study was to assess risk factors of contracting SARS-CoV-2 infection in PwMS by using data collected in the Italian MS Register (IMSR). METHODS: A case-control (1:2) study was set up. Cases included PwMS with a confirmed diagnosis of COVID-19, and controls included PwMS without a confirmed diagnosis of COVID-19. Both groups were propensity score-matched by the date of COVID-19 diagnosis, the date of last visit, and the region of residence. No healthy controls were included in this study. COVID-19 risk was estimated by multivariable logistic regression models including demographic and clinical covariates. The impact of DMTs was assessed in 3 independent logistic regression models including one of the following covariates: last administered DMT, previous DMT sequences, or the place where the last treatment was administered. RESULTS: A total of 779 PwMS with confirmed COVID-19 (cases) were matched to 1,558 PwMS without COVID-19 (controls). In all 3 models, comorbidities, female sex, and a younger age were significantly associated (p < 0.02) with a higher risk of contracting COVID-19. Patients receiving natalizumab as last DMT (OR [95% CI]: 2.38 [1.66-3.42], p < 0.0001) and those who underwent an escalation treatment strategy (1.57 [1.16-2.13], p = 0.003) were at significantly higher COVID-19 risk. Moreover, PwMS receiving their last DMT requiring hospital access (1.65 [1.34-2.04], p < 0.0001) showed a significant higher risk than those taking self-administered DMTs at home. DISCUSSION: This case-control study embedded in the IMSR showed that PwMS at higher COVID-19 risk are younger, more frequently female individuals, and with comorbidities. Long-lasting escalation approach and last therapies that expose patients to the hospital environment seem to significantly increase the risk of SARS-CoV2 infection in PwMS. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that among patients with MS, younger age, being female individuals, having more comorbidities, receiving natalizumab, undergoing an escalating treatment strategy, or receiving treatment at a hospital were associated with being infected with COVID-19. Among patients with MS who were infected with COVID-19, a severe course was associated with increasing age and having a progressive form of MS, whereas not being on treatment or receiving an interferon beta agent was protective.