The Observation of Humoral Responses after Influenza Vaccination in Patients with Rheumatoid Arthritis Treated with Japanese Oriental (Kampo) Medicine: An Observational Study

Abstract

Objective. The efficacy of influenza vaccination in patients treated with Japanese Oriental (Kampo) Medicine is unknown. The objectives of this study were to observe the efficacy of influenza vaccination in RA patients treated with Kampo. Methods. Trivalent influenza subunit vaccine was administered to 45 RA patients who had received Kampo. They were divided into 2 groups: RA patients treated without MTX (“without MTX group”) and treated with MTX (“with MTX group”). Antibody titers were measured before and 4 weeks after vaccination using hemagglutination inhibition assay. Results. Geometric mean titers (GMTs) of anti-influenza antibodies significantly increased for all influenza strains. Response to the influenza vaccination in RA patients treated with Kampo was not lower than that of healthy subjects and the response in the “with MTX group” had a tendency to be higher than that in RA patients treated with MTX in the previous study. There was no significant difference in the GMT after 4 weeks between the “with MTX group” and the “without MTX group.” A decreased efficacy in both seroprotection and seroconversion was not found in the “with MTX group.” Conclusion. These observations may open the way for further clinical trials to establish the efficacy for the influenza vaccination in RA patients treated with Kampo.

Efficacy, immunogenicity and safety of vaccination in adult patients with autoimmune inflammatory rheumatic diseases: a systematic literature review for the 2019 update of EULAR recommendations

“…Influenza vaccination did not influence activity of the underlying AIIRD in patients with RA,7 8 12 14 15 38 39 42 54 55 57 71–73 SLE,6 19 21 26 28 37 43 45–47 ANCA-associated vasculitis30 31 48 or systemic sclerosis 32 49. Adverse events of influenza vaccination in patients with AIIRD were comparable to those in HCs in most studies,7 19 21 23 30 59 65 including a meta-analysis in patients with SLE,46 In contrast, a meta-analysis including 13 studies in patients with RA concluded that local, mild adverse events occurred significantly more frequently in patients with RA 42…”

“…The influence of immunomodulating agents on influenza vaccine efficacy and immunogenicity is summarised in table 6. No influence of methotrexate (MTX) on influenza immunogenicity was found in most studies39 40 43 62 72 74 including one meta-analysis in patients with RA 75. In some, a modest reduction in immunogenicity was observed 58–60 73 76.…”