Key clinical point: Ultra-low dosing and repeated COVID-19 vaccination as late as possible after the latest rituximab infusion seems to be the best vaccination strategy in rituximab-treated patients with rheumatoid arthritis (RA).
Major finding: Humoral response after the third COVID-19 vaccination was numerically higher with 200 vs 1000 mg as the latest rituximab dose for the first vaccination (38% vs 15%; P = .06), with a trend toward improved response observed with a longer time between rituximab infusion and vaccination (odds ratio 1.16 per month increased time; P = .10). Overall, the humoral response persisted in 96% of patients, with response being persistent in 89% of patients despite intercurrent rituximab infusion.
Study details: Findings are from a follow-up study of the RTX-COVAC cohort including 121 rituximab-treated patients with RA who received a third COVID-19 vaccination.
Disclosures: This study did not receive any funding. AA den Broeder reported receiving grants outside the submitted work from various sources. The other authors declared no conflicts of interest.
Source: van der Togt CJT et al. Seroconversion after a third COVID-19 vaccine is affected by rituximab dose but persistence is not in patients with rheumatoid arthritis. Rheumatology (Oxford). 2022 (Aug 24). Doi: 10.1093/rheumatology/keac486