Safety of infusing rituximab at a more rapid rate in patients with rheumatoid arthritis: results from the RATE-RA study.

Background: As recommended in the current prescribing information, rituximab infusions in patients with rheumatoid arthritis (RA) take 4.25 hours for the first infusion and 3.25 hours for subsequent infusions, which is a burden on patients and the health care system. We therefore evaluated the safety of infusing rituximab at a faster rate for an infusion period of 2 hours in patients with RA.

Methods: Patients with an inadequate response to anti-TNF who were rituximab-naive or -experienced received 2 courses of rituximab: Infusion 1 (Day 1) was administered over the standard 4.25 hours, and Infusions 2 (Day 15), 3 (Day 168) and 4 (Day 182) were administered over a faster 2-hour period. The primary endpoint was incidence of infusion-related reactions (IRRs) associated with Infusion 2.

Results: Of the 351 patients enrolled, 87% and 13% were rituximab-naive and -experienced, respectively. The incidence (95% CI) of IRRs associated with Infusion 1 was 16.2% (12.5%, 20.5%) and consistent with weighted historical incidence of 20.7% (19.4%, 22.1%). The incidence (95% CI) of IRRs associated with Infusions 2, 3, and 4 compared with respective weighted historical incidences at the standard infusion rate was 6.5% (4.1%, 9.7%) vs 8.1% (7.2%, 9.1%); 5.9% (3.5%, 9.3%) vs 11.5% (10.3%, 12.8%); and 0.7 (0.1%, 2.6%) vs 5.0% (4.2%, 6.0%), respectively. All IRRs were grade 1 or 2, except for 3 grade 3 IRRs associated with Infusion 1 and 2 grade 3 IRRs associated with Infusion 2. Four patients experienced a total of 5 grade 3 IRRs; 3 of these patients continued on to received subsequent infusions at the faster rate. There were no serious IRRs.

Conclusion: This study demonstrated that rituximab can be administered at the faster infusion rate at the second and subsequent infusions without increasing the rate or severity of IRRs.