ABSTRACT
Background/Purpose: The immunogenicity data of mRNA SARS-CoV- 2 vaccine boosted after completed primary series beyond mRNA vaccine in autoimmune rheumatic disease (ARDs) patients is sparse. We report the vaccine immunogenicity of SAR-CoV2 mRNA vaccine booting after completed heterologous CoronaVac followed by ChAdOx1 nCoV-19 (SV-AZ) or homologous ChAdOx1 nCoV-19 vaccination (AZ-AZ). Method(s): The levels of SARS-CoV- 2 anti-RBD IgG were evaluated at one and three months after mRNA vaccine booster in adults with ARDs who completed the heterologous CoronaVac-ChAdOx1 nCoV-19 vaccine (n = 19) or homologous ChAdOx1 nCoV-19 (n = 13) within 90-180 days. All patients were received at least one immunosuppressive drug as follows: prednisolone <20 mg/day, methotrexate >=10 mg/week, azathioprine >=50 mg/day, mycophenolate mofetil >=1,000 mg/day, or leflunomide >=10 mg/day, as a stable dose for a month prior vaccination. Anti-RBD antibody was measured. Seropositivity was defined as IgG >=42 binding antibody units (BAU)/ mL. Disease activity was evaluated. Result(s): Among 33 ARDs, 78.8% were female, mean (SD) age was 42.9 years. Half of them were SLE (54.5%). Most patients received corticosteroid (75.8%), mean (IQR) dose of 7.5 (5, 7.5) mg/day of prednisolone. The immunosuppressive drugs used were as follows;azathioprine (45.5%), methotrexate (39.4%) and mycophenolate mofetil (21.2%). The anti-RBD IgG was positive in all SV-AZ group while one patient in AZ-AZ who received mycophenolate mofetil was seronegative. At one-month post mRNA booster, the median (IQR) anti-RBD IgG levels trended to be lower among patients with AZ-AZ than among SV-AZ primary series (1867.8 [591.6, 2548.6] vs. 3735.8 [2347.9, 5014.0] BAU/mL, P = 0.061). Mean (SD) anti-RBD IgG level in the AZ-AZ group was significantly lower than SV-AZ group at three-month post mRNA boosters (597.8 [735.5] vs. 1609.9 [828.4] BAU/mL, P = 0.003). Disease flare-ups occurred in six patients (18.2%), and all were minor flares. Conclusion(s): Our findings demonstrated satisfactory humoral immunogenicity of mRNA booster after primary series with the vaccine strategies rather than mRNA platform. SAR-CoV2 vaccine-induced immunity trend to lower in AZ-AZ primary series. The fourth dose in this subgroup might be a consideration without delay. However, this finding needs to be confirmed by a larger study. (Table Presented).
ABSTRACT
Background: As the COVID-19 pandemic continues, most of the world population are now recommended to have the 3rd dose COVID-19 vaccination (booster dose). However, details of humoral immune response after the booster dose vaccine are scarce, especially in patients with cirrhosis. We studied the antibody (Ab) responses in patients with cirrhosis after receiving the different type of booster vaccines. Method(s): We conducted a prospective observational study of patients with cirrhosis who had completed prior two doses of COVID-19 vaccines and voluntarily received their booster dose between Nov 2021 and April 2022. The types of vaccine were according to the government policy and patients' preference, the investigators had no role in the selection of the type of the booster vaccine. Patients who had history of SARS-CoV- 2 infection after the second dose of vaccination, and ones who obtained immunosuppressive drugs were excluded. The patients' blood samples were collected at three time-points i.e., before the first dose vaccination, 4-week post the 2nd dose of vaccination, and after the booster dose vaccine for 4 weeks. The anti-spike receptor-binding domain protein (RBD) IgG was measured using the Abbott SARS-CoV- 2 IgGIIQuant assay to determine Ab response. The comparisons between 2 types of booster vaccine were analysed: ChAdOx1-nCoV- 19 vaccine (AZ) and mRNA vaccine (BNT162b2 Pfizer-BioNTech or mRNA-1273 Moderna). Result(s): A total of 24 patients with cirrhosis who received a booster dose SARS-CoV- 2 vaccine were eligible. Nine patients got AZ vaccine, whereas 15 patients received mRNA vaccine. Baseline characteristics were similar between both groups, the mean age was 65.6+11.1 and 60.1+14.8 years in the AZ and mRNA groups, respectively (p=0.353), 75% were in CTP class A. The primary regimens for the first 2 doses were similar between the two groups (p=0.217). Post-booster Ab titers in mRNA vaccine were nonsignificantly higher than in AZ vaccine (4566.8+3706.7 vs 1960.5+2434.1 BAU/mL, P=0.74). Of note, the changes of Ab titers after the 3rd dose compared to the 2nd dose in patients who received mRNA vaccine were significantly higher than those who received AZ vaccine (the median change of +2523.7 [IQR: 1365.6,6924.5] vs +398 (IQR: -87.8,1015.6), P=0.015). Additionally, one patient from each groups (AZ/AZ/AZ =1, AZ/AZ/PZ =1) developed symptomatic COVID-19 after the booster dose and all had mild symptoms. Conclusion(s): In patients with cirrhosis, one who received a booster dose with mRNA vaccine had a greater Ab responses more than that in AZ vaccine. Further research exploring in a larger number of patients is warrant to aid selecting the booster vaccine of choice for cirrhotic patients. (Figure Presented).