Efficacy and tolerability of a third dose of an mRNA anti-SARS-CoV-2 vaccine in patients with rheumatoid arthritis with absent or minimal serological response to two previous doses.

Abstract

Vaccine-induced immunity is crucial to combat the COVID-19 pandemic, but titres of antibodies against the SARS-CoV-2 spike protein 1 (S1) can decrease over time.1 The efficacy of a third vaccine dose was recently reported in people aged older than 60 years who had received two doses of BNT162b2 (Pfizer-BioNTech) at least 5 months earlier.2 A significant proportion of patients under immunosuppression (solid organ transplant recipients and patients with autoimmune diseases) with a previously inadequate anti-S1 response after two vaccine doses seroconverted after an additional vaccine dose.