Comparison of the Inhibitory Effects Between Bepotastine and Diphenhydramine on Rituximab-Induced Infusion-Related Reactions: A Single-Center Retrospective Study

Purpose Infusion-related reaction (IRR) is a common adverse event induced by rituximab. Although first-generation histamine 1 receptor antagonists (H1RAs) are commonly used for the prevention of IRR, evidence is scarce on the incidence of IRR suppression with the second-generation H1RA bepotastine. This study assessed inhibitory effects of bepotastine on rituximab-induced IRR and compared them with those of first-generation H1RA diphenhydramine. Methods We retrospectively evaluated IRR incidence in patients with B-cell non-Hodgkin’s lymphoma who received their first dose of rituximab. Results The incidence of IRR was 9.8% in the bepotastine group (n = 92), which was significantly lower than the 30.2% incidence rate in the diphenhydramine group (n = 96; p < 0.001). The median IRR onset time after rituximab administration in the bepotastine group was 60 min, which was significantly shorter than the 120 min of the diphenhydramine group (p = 0.002). Multivariable logistic regression analysis revealed that the risk of IRR incidence was higher in patients with B symptoms (odds ratio [OR] = 2.96, 95% confidence interval [CI]: 1.20–7.27) and bulky disease (OR = 9.12, 95% CI: 2.53–32.9). Bepotastine use as premedication was an independent factor reducing the risk of IRR incidence (OR = 0.19, 95% CI: 0.08–0.47). Conclusion Bepotastine more effectively reduced the incidence of rituximab-induced IRR than diphenhydramine, particularly delayed-type reactions.