Objectives
To evaluate the impact of medication on antibody response to SARS-CoV-2 mRNA vaccines in Japanese patients with rheumatic diseases.
Methods
This prospective multicenter cohort study evaluated the humoral response in 12 different medication groups. Antibody levels before the first vaccination and 3-6 weeks after the second vaccination were measured using the Elecsys Anti-SARS-CoV-2 S assay. Statistical analysis included comparing antibody titers among the different medication groups using the Kruskal–Wallis test followed by the Bonferroni–Dunn test and multiple linear regression analysis.
Results
Two hundred and ninety-five patients were analyzed. The seroconversion rate was 92.2% and the median antibody titer was 255 U/ml (interquartile range, 34.1-685) after the second mRNA vaccination. Antibody levels were significantly lower in the groups treated with TNF inhibitor (TNFi) with methotrexate (MTX), abatacept, mycophenolate mofetil (MMF), MMF or mizoribine (MMF/MZR) combined with calcineurin inhibitor (CNI), and rituximab or cyclophosphamide (RTX/CPA) compared with those treated with sulfasalazine and/or bucillamine or CNI (p<0.01). The correlation between antibody titer and treatment was significant after adjusting for age, gender, and glucocorticoid dose (p<0.01).
Conclusions
Additional early vaccination is required in patients treated with TNFi and MTX, abatacept, MMF, MMF or MZR combined with CNI and CPA/RTX.