- What is the clinical effectiveness of rituximab maintenance therapy for the treatment and management of rheumatoid arthritis?
Five non-randomized studies were included in this review, of which three were single-arm studies and two were comparative cohorts. The studies were of poor quality overall, many with small sample sizes, no comparator group, large number of patient drop-outs, and the presence of differences in baseline characteristics among groups within studies. The studies were also hampered by incomplete reporting, such as not specifying whether patients had responded to an initial cycle of rituximab infusion prior to receiving maintenance therapy, the number of rituximab cycles received, or the maintenance doses of rituximab administered. Furthermore, the applicability of the evidence base to Canadian rheumatology practice settings is unclear because all studies were conducted in other countries.In a large comparative study (N = 800) that compared fixed interval rituximab retreatment versus on-flare retreatment up to a total of three cycles, the Disease Activity Score 28 (DAS28) improvement from the start of therapy was statistically greater for the fixed interval group after both first and second retreatments. However, the results of this study must be interpreted with caution due to the potential for confounding by indication. Another, smaller, comparative study (N = 102) found no statistically significant differences in efficacy outcomes. The single-arm studies examined rituximab maintenance infusion on remission, DAS28, and safety. Based on the evidence reviewed, the relative benefits and safety of rituximab maintenance therapy compared with flare-based retreatment are unclear and more comparative studies are needed reduce uncertainty.