Safety and effectiveness of the booster dose of mRNA COVID-19 vaccines in people with multiple sclerosis: a monocentric experience

Background Long-term data on the effectiveness and safety of the booster dose of anti-SARS-CoV-2 vaccines in people affected by multiple sclerosis (pwMS) are lacking, hence a retrospective monocentric study exploring these issues was undertaken. Materials and methods : PwMS who had received the booster dose of anti-COVID19 mRNA vaccines (either Comirnaty or Spikevax) according to the national regulation were included. The occurrence of adverse events or disease reactivation and SARS-CoV-2 infection were recorded up to last follow-up. Factors predictive of COVID-19 were explored using logistic regression analyses. A two-tailed p-value <0.05 was considered significant. Results : One hundred and fourteen pwMS were included: 80 females (70%);median age at the booster dose 42 years (range 21 – 73);106/114 patients (93%) were receiving a disease-modifying treatment at vaccination. The median follow-up after the booster dose was 6 (range 2 – 7) months. Adverse events were experienced in 58% of the patients, being mild to moderate in most cases;4 reactivations of MS were observed, two of which occurring within 4 weeks after the booster. SARS-CoV-2 infection was reported in 24/114 (21%) cases, occurring a median of 74 days (5-162) after the booster dose and requiring hospitalisation in 2 patients. Six cases received direct antiviral drugs. Age at vaccination and time between the primary vaccination cycle and the booster dose were independently and inversely associated with the risk of COVID-19 (HR 0.95 and 0.98, respectively). Conclusions : The administration of the booster dose in pwMS showed an overall good safety profile and protected 79% of the patients from SARS-CoV-2 infection. The observed association between the risk of infection after the booster dose and both younger age at vaccination and shorter interval period to the booster dose suggest that unobserved confounders, possibly including behavioural and social factors, play a relevant role in determining the individual propensity to get infected with COVID-19.

Safety and effectiveness of the booster dose of mRNA COVID-19 vaccines in people with multiple sclerosis: A monocentric experience.

BACKGROUND: Long-term data on the effectiveness and safety of the booster dose of anti-SARS-CoV-2 vaccines in people affected by multiple sclerosis (pwMS) are lacking, hence a retrospective monocentric study exploring these issues was undertaken. MATERIALS AND METHODS: PwMS who had received the booster dose of anti-COVID19 mRNA vaccines (either Comirnaty or Spikevax) according to the national regulation were included. The occurrence of adverse events or disease reactivation and SARS-CoV-2 infection were recorded up to last follow-up. Factors predictive of COVID-19 were explored using logistic regression analyses. A two-tailed p-value <0.05 was considered significant. RESULTS: One hundred and fourteen pwMS were included: 80 females (70%); median age at the booster dose 42 years (range 21 - 73); 106/114 patients (93%) were receiving a disease-modifying treatment at vaccination. The median follow-up after the booster dose was 6 (range 2 - 7) months. Adverse events were experienced in 58% of the patients, being mild to moderate in most cases; 4 reactivations of MS were observed, two of which occurring within 4 weeks after the booster. SARS-CoV-2 infection was reported in 24/114 (21%) cases, occurring a median of 74 days (5-162) after the booster dose and requiring hospitalisation in 2 patients. Six cases received direct antiviral drugs. Age at vaccination and time between the primary vaccination cycle and the booster dose were independently and inversely associated with the risk of COVID-19 (HR 0.95 and 0.98, respectively). CONCLUSIONS: The administration of the booster dose in pwMS showed an overall good safety profile and protected 79% of the patients from SARS-CoV-2 infection. The observed association between the risk of infection after the booster dose and both younger age at vaccination and shorter interval period to the booster dose suggest that unobserved confounders, possibly including behavioural and social factors, play a relevant role in determining the individual propensity to get infected with COVID-19.

Safety and tolerability of SARS-Cov-2 vaccination in patients with myasthenia gravis: A multicenter experience.

BACKGROUND AND PURPOSE: During the COVID-19 pandemic, myasthenia gravis (MG) patients have been identified as subjects at high risk of developing severe COVID-19, and thus were offered vaccination with priority. The lack of direct data on the safety and tolerability of SARS-CoV-2 vaccines in MG have contributed to vaccine hesitancy. To address this issue, the safety and tolerability of SARS-CoV-2 vaccines were assessed in a large cohort of MG patients from two referral centers. METHODS: Patients with confirmed MG diagnosis, consecutively seen between October and December 2021 at two MG centers, were enrolled. Demographics, clinical characteristics, and information regarding SARS-CoV-2 infection/vaccination were extracted from medical reports and/or collected throughout telephonic or in-person interviews. RESULTS: Ninety-eight (94.2%) of 104 patients included were administered at least two vaccine doses 4 weeks before the interview or earlier, and among them, 63 of 98 (64.2%) have already received the "booster" dose. The most frequently used vaccines were BNT162b2-Pfizer-BioNTech and mRNA-1273-Moderna. Overall, only minor side effects were reported, most commonly local pain and fever. MG worsening after vaccination was observed in eight of 104 (7.7%) cases. The frequency of worsening among muscle-specific tyrosine kinase MG cases (3/9, 33.3%) was significantly higher compared to other serological subgroups. Spontaneous symptom regression was observed in six of eight cases. Twelve of 104 (11.5%) patients had SARS-CoV-2 infection, and none of the SARS-CoV-2-infected MG patients worsened after vaccination. CONCLUSIONS: Our data support the safety and tolerability of mRNA COVID-19 vaccines, which should be strongly recommended in MG patients, who could be at higher risk of complications if exposed to SARS-CoV-2 infection.

Effect of disease-modifying treatments on antibody-mediated response to anti-COVID19 vaccination in people with multiple sclerosis.

BACKGROUND: Few data are available so far on the antibody-mediated immune response to anti-SARS-Cov2 vaccination in people with multiple sclerosis (pwMS) treated with disease-modifying treatments (DMTs), therefore this issue was explored in a real-life cohort of pwMS. MATERIALS AND METHODS: Retrospective monocentric study on anti-spike protein antibody response in pwMS who had received vaccination for Sars-Cov2. Adverse events following vaccination were also recorded. RESULTS: One hundred and twenty pwMS were included: 83 females (69%); median age at vaccination 42 years (range 21-73); 112/120 patients (93%) were receiving DMTs at vaccination. Anti-spike protein IgG antibodies were detectable in 102/120 (85%) cases overall, being the proportion lower in pwMS receiving anti-CD20 antibodies (14/31, 45%) compared to non-depletive treatments (77/78, 99%), p < 0.0001. Median anti-spike titre was lower in anti-CD20 antibodies and fingolimod-treated pwMS compared to those receiving other DMTs, and it correlated with anti-CD20 treatment duration (R - 0.93, p < 0.0001) and with age at vaccination in pwMS not receiving depletive treatments (R - 0.25, p = 0.028). Baseline CD19+ cell count (where available) was higher in the responder group than in non-responders, p < 0.0001. Two symptomatic COVID-19 infections were diagnosed over a median follow-up of 5 months (range 2-7); adverse events were aligned with the published literature. CONCLUSION: Antibody response to anti-COVID-19 vaccines was detected in most of the pwMS analysed, but frequency of responders was reduced in those receiving CD20 depleting therapies compared to other DMTs-treated pwMS. Investigations on cell-mediated immune response are needed to assess whether a protective immune response is elicited also in non-antibody responders.