Cross-sectional analysis of the humoral response after SARS-CoV-2 vaccination in Sardinian Multiple Sclerosis patients, a follow-up study (preprint)

Monitoring immune responses to SARS-CoV-2 vaccination and its clinical efficacy over time in Multiple Sclerosis (MS) patients treated with disease-modifying therapies (DMTs) help to establish the optimal strategies to ensure adequate COVID-19 protection without compromising disease control offered by DMTs. Following our previous observations of the humoral response one month after two doses of BNT162b2 vaccine (T1) in MS patients differently treated, here we present a cross-sectional and longitudinal follow-up analysis six months following vaccination (T2, n=662) and a month following the first booster (T3, n=185). Consistent with results at T1, humoral responses were decreased in MS patients treated with fingolimod and anti-CD20 therapies compared with untreated patients also at the time points considered here (T2 and T3). Interestingly, a strong upregulation one month after the booster was observed in patients under every DMTs analyzed, including those treated with fingolimod and anti-CD20 therapies. And although patients taking these latter therapies had a higher rate of COVID-19 infection five months after the first booster, only mild symptoms that did not require hospitalization were reported for all the DMTs analyzed here. Based on these findings we anticipate that additional vaccine booster shots will likely further improve immune responses and COVID-19 protection in MS patients treated with any DMT.

Multiple sclerosis disease-modifying therapies and COVID-19 vaccines: A practical review and meta-analysis (preprint)

Importance: An evidence-based appraisal of the COVID-19 vaccination policies among people with multiple sclerosis (pwMS) with respect to disease-modifying therapies (DMT) is important for our understandings and their further management. Objective: To synthesize the available evidence concerning the effect of DMTs on COVID-19 vaccination immunogenicity and effectiveness. Data Sources: We searched MEDLINE, Scopus, Web of Science, MedRxiv, and Google Scholar from January 2021 until January 2022. Study Selection: The exclusion criteria included: not a primary investigation; retracted/withdrawn; no eligible participants - people with no history/evidence of previous COVID-19 and corticosteroid administration within two months of vaccination; no eligible exposures - all nine DMT classes; and no eligible comparators - DMT-unexposed at the time of vaccination. Data Extraction and Synthesis: Entries were assessed independently by two reviewers for eligibility and quality. Dichotomized data was extracted by two reviewers in accordance with Cochrane guidelines, and were pooled using either Peto fixed-effects or Inverse-variance random-effects methods. Main Outcomes and Measures: Main outcomes were i) B-cell response, measured by seroconversion odds ratio (OR); ii) T-cell response, measured by interferon-gamma release response OR, and CD4+/CD8+ activation-induced marker+ OR. Further outcomes including immunity waning speed and breakthrough COVID-19 incidence/severity were synthesized narratively. Results: Data from 28 studies (5,025 pwMS and 1,635 healthy participants) after COVID-19 vaccination suggests mildly-lower B-cell responses in teriflunomide- and alemtuzumab-treated, extensively-lower B-cell responses in sphingosine-1-phosphate receptor modulator (S1PRM)- and anti-CD20 (aCD20)-treated, and lower T-cell responses in interferon-, S1PRM-, alemtuzumab- and cladribine-treated pwMS. Every ten-week increase in aCD20-to-vaccine period is associated with a 1.94-time (95%CI: 1.57, 2.41, P<0.00001) increase in odds of seroconversion. B-cell-depleting therapies seem to accelerate post-vaccination humoral waning, and booster immunogenicity is predictable with the same factors affecting the priming vaccination. Furthermore, comparatively-increased breakthrough COVID-19 incidence and severity is being observed only among S1PRM- and anti-CD20-treated pwMS - i.e., among the pwMS with extensively-blunted B-cell response, despite adequate T-cell responses in the aCD20-treated. To date, pwMS on only-T-cell-blunting DMTs have not shown increased susceptibility to breakthrough COVID-19. Conclusion and Relevance: The implemented vaccination strategy to date has been effective for pwMS on all DMTs other than S1PRM and aCD20. As B-cell immunity seems to be a more important predictor of vaccine effectiveness than T-cell immunity, optimization of humoral immunogenicity and ensuring its durability among pwMS on DMTs are the necessities of an effective COVID-19 vaccination policy.

Effect of different disease-modifying therapies on humoral response to BNT162b2 vaccine in Sardinian multiple sclerosis patients (preprint)

ObjectivesVaccination against COVID-19 is highly recommended to patients affected by multiple sclerosis (MS); however, the impact of MS disease-modifying therapies (DMTs) on the immune response following vaccination has been only partially investigated. Here, we aimed to elucidate the effect of DMTs on the humoral immune response to mRNA-based anti-SARS-CoV-2 vaccines in MS patients. MethodsWe obtained sera from 912 Sardinian MS patients and 63 healthy controls 30 days after the second dose of BNT162b2 vaccine and tested them for SARS-CoV-2 response using anti-Spike (S) protein-based serology. Previous SARS-CoV-2 infection was assessed by anti-Nucleocapsid (N) serology. Patients were either untreated or undergoing treatment with a total of 13 different DMTs. Differences between treatment groups comprised of at least 10 patients were assessed by generalized linear mixed-effects model. Demographic and clinical data and smoking status were analyzed as additional factors potentially influencing humoral immunity from COVID-19 vaccine. ResultsMS patients treated with natalizumab, teriflunomide, azathioprine, fingolimod, ocrelizumab, and rituximab showed significantly lower humoral responses compared to untreated patients. We did not observe a statistically significant difference in response between patients treated with the other drugs (dimethyl fumarate, interferon, alemtuzumab and glatiramer acetate) and untreated patients. In addition, older age, male, sex and active smoking were significantly associated with lower antibody titers against SARS-CoV-2. MS patients previously infected with SARS-CoV-2 had significantly higher humoral responses to vaccine than uninfected patients. ConclusionHumoral response to BNT162b2 is significantly influenced by the specific DMTs followed by patients, as well as by other factors such as previous SARS-CoV-2 infection, age, sex, and smoking status. These results are important to inform targeted strategies to prevent clinically relevant COVID-19 in MS patients.