The frequency and associated factors of infusion-related reactions to rituximab for patients with rheumatoid arthritis

Objectives: Rituximab is an effective biological agent for treating patients with rheumatoid arthritis (RA). Rheumatologists can avoid rituximab therapy because of infusion-related reactions (IRR). There is a lack of data about rituximab-related IRR, especially in rituximab-naïve patients with RA; therefore, we aimed to determine the frequency and associated factors of rituximab-related IRR in these patients. Methods: Baseline demographic, laboratory, and treatment data were noted. One course of rituximab was used in two infusions to 95 rituximab-naïve patients with RA. Standardized premedication was administered before infusions. Rates, severity, and management of IRR were recorded. Efficacy and infections were also noted if there were. Results: Ninety-four of 95 patients completed the rituximab course successfully. We observed a total of 23 IRRs in 20 patients. The frequency of IRR was 12.1%, and serious IRR was 0.52%. Grade 1-2-3 IRRs had a rate of 52.2%, 30.4%, and 17.4%, respectively; grade 4 or 5 IRR wasn’t detected. Age <60 years, anti-CCP <200U/ml and absence of biologic agent use before rituximab was significantly higher in patients with IRR than without IRR (p=0.01, p=0.002, p=0.01 respectively). We found out that if only the disease age is above 60 months, it is protective against IRR as per the results of multivariate model analysis. Conclusion: Results supported that rituximab is a safe biological agent option for patients with RA at secondary central hospitals. Identified risk factors of IRR need to be corroborated in larger studies for safer rituximab therapy.