Key clinical point: Retreatment with a lower rituximab dose of 200 mg or 500 mg was as effective as 1000 mg in patients with rheumatoid arthritis (RA) who responded well to standard rituximab dose.
Major finding: Treatment response was not maintained in 11%, 21%, and 13% of patients in the 1000 mg, 500 mg, and 200 mg rituximab groups, respectively. Ultra-low rituximab dosage was not associated with the presence of antidrug antibodies at 6 months, and B-cell counts were not significantly different between the dosing groups.
Study details: The data comes from a preplanned secondary analysis of the REDO trial involving 140 patients with RA who responded well to the standard rituximab dose for at least 6 months and were randomly assigned to receive 200 mg, 500 mg, or 1000 mg rituximab.
Disclosures: The REDO study was funded by health insurance companies Centraal Ziekenfonds and Menzis, and this secondary analysis did not receive any external funding. The Sint Maartenskliniek (employer of 6 authors) has a patent application filed for rituximab in the treatment of polymyalgia rheumatica.
Source: Wientjes MHM et al. Rheumatology (Oxford). 2022 (Jan 12). Doi: 10.1093/rheumatology/keac024