TNF inhibitors significantly attenuate the humoral immune response to COVID-19 vaccination in patients with rheumatoid arthritis

OBJECTIVE: Several studies on the immunogenicity of vaccination against coronavirus disease 2019 (COVID-19) in patients with immune-mediated inflammatory diseases have evaluated the influence of DMARDs. The aim of the work presented here was to compare the humoral vaccine response after two vaccinations between patients with RA undergoing TNF inhibitor therapy and healthy controls. METHODS: We assessed the humoral immune response, as measured by titres of neutralizing antibodies against the S1 antigen of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in patients with RA and anti-TNF treatment vs. controls without immunomodulatory medication. One hundred and seven fully vaccinated individuals were included at 6 ± 1 weeks after the second vaccination [BioNTech/Pfizer (72.9%), AstraZeneca (17.8%) and Moderna (9.3%)]. Immune responses in terms of antibody titres were compared between both subgroups with (n = 45) and without (n = 62) exposure to anti-TNF medication. The comparison was performed as a cross-sectional, single-centre study approach using non-parametric tests for central tendency. RESULTS: Anti-TNF medication produced a significantly impaired humoral immune response to vaccination against COVID-19. The maximum immune response was detected in 77.4% of control patients, whereas this decreased to 62.2% in participants treated with TNF inhibitors (P = 0.045; effect size, d = 0.194). Patients on combination treatment (anti-TNF medication and MTX, 17 of 45 subjects in the treatment group) did not differ significantly regarding humoral immune response compared with patients on monotherapy with TNF inhibitors only (P = 0.214). CONCLUSION: TNF inhibitors significantly reduce the humoral response following dual vaccination against COVID-19 in patients with RA.