Safety and Tolerability of a 90-minute Infusion of Originator and Biosimilar Rituximab in Rituximab- Naïve Patients

This study aimed to investigate the safety and tolerability of 90-min rapid infusion of rituximab, originator or biosimilar (Truxima), for rituximab-naïve patients with hematologic malignancy. We undertook a retrospective review of records of 118 patients (81 originator rituximab and 37 Truxima) with hematologic malignancy who had received rituximab rapid infusion from the first cycle of chemotherapy with corticosteroid premedication administration. Most patients had high Ann Arbor stage (80.9%), high International Prognostic Index risk (69.1%), favorable performance status (98.3%), and high lactate dehydrogenase level (78.8%). The patients received a collective total of 717 rapid rituximab infusions, with an average of 6 infusions per patient (range, 1-8). The incidence of infusion-related reactions (IRRs) of any grade and grade 3/4 during first infusion was 21.2% and 0.8%, respectively. No episode of grade 3/4 IRR was observed during the second and subsequent rituximab infusions. Severity and type of IRRs in Truxima administration were comparable to those of originator rituximab. This study suggests that 90-minute rituximab infusion with the first dose of chemotherapy was well tolerated. In terms of IRR, safety profiles of Truxima were comparable to that of originator rituximab, suggesting that Truxima might replace originator rituximab in a rapid infusion setting.