The Efficacy and Safety of Different Dosages of Rituximab for Adults with Immune Thrombocytopenia: A Systematic Review and Meta-Analysis

Abstract

Background. Rituximab has been frequently used as a second-line treatment for patients with immune thrombocytopenia (ITP). The optimal dose and course of rituximab are uncertain. Methods. A comprehensive search for randomized controlled trials reporting the use of low-dose (100 mg) or standard-dose (375 mg/m2) rituximab in ITP treatment was conducted. Meta-analyses were performed on CRR (complete response rate), ORR (overall response rate), PRR (partial response rate), SRR (sustained response rate), infection rate, SB (significant bleeding) rate, and SAE (serious adverse event) rate. Results. A total of 12 studies were included, comprising 869 patients. Compared to the control group, rituximab treatment resulted in an obvious increase in CRR ( P < 0.00001 ), ORR ( P < 0.0001 ), and SRR at month 6 and 12 ( P = 0.0007 , P = 0.0003 ), without increasing the infection rate ( P = 0.12 ) and SAE rate ( P = 0.11 ). No significant differences in CRR (RR 1.61 vs. 1.42, P = 0.45 ), ORR (RR 1.26 vs. 1.49, P = 0.28 ), PRR (RR 1.25 vs. 1.00, P = 0.11 ), SRR at month 12 (RR 2.00 vs. RR 1.64, P = 0.54 ), infection rate (RR 0.85 vs. 1.46, P = 0.36 ), and SB rate (RR 0.14 vs. 1.19, P = 0.17 ) were found in subgroups of low dose and standard dose. Conclusion. Rituximab was effective and safe for adult patients with ITP. A low-dose rituximab regimen might be an effective alternative to the standard-dose regimen in ITP, as it showed similar CRR, ORR, and SRR at month 12 and was relatively safer with a lower cost.

Optimal dose of rituximab in ABO‐incompatible kidney transplantation in patients with low anti‐A/B antibody titers: A single‐center retrospective cohort study

“…[20][21][22][23][24][25][26][27][28][29][30][31][32][33] It has been reported that it not only suppresses CD20 + B cells but also increases the risk of infection in a dose-dependent manner. [34][35][36] Therefore, an optimal dose of rituximab that effectively prevents AMR and does not increase the risk of infection has been sought.…”

“…Several studies have demonstrated that rituximab contributes to an increase in or aggravation of coronavirus disease‐2019 infections 20–33 . It has been reported that it not only suppresses CD20 + B cells but also increases the risk of infection in a dose‐dependent manner 34–36 . Therefore, an optimal dose of rituximab that effectively prevents AMR and does not increase the risk of infection has been sought.…”

Three cases of refractory bullous pemphigoid in the elderly treated successfully with ultra‐low‐dose rituximab

“…A phase I study with rituximab in 1994 confirmed a single 100 mg/m 2 injection was sufficient to deplete all CD 20 cells in the peripheral blood 8 . Ultra‐low‐dose rituximab (100 mg qw for 4 weeks) has been reported to be effective in many autoimmune diseases, such as rheumatoid arthritis 9 and immune thrombocytopeni 10 . Based on these previous experiences, ultra‐low‐dose rituximab (100 mg weekly for 4 weeks) maybe a feasible regimen for BP.…”

How we treat primary immune thrombocytopenia in adults

“…The short-term response rates range from 60 to 70% in patients treated with the standard 4 weekly doses of 375 mg/m 2 rituximab, and the response is usually achieved within 4–8 weeks [ 141 ]. Alternative dosing schedules of rituximab, such as 100 mg/week for 4 weeks, 1000 mg on day 1 and day 15, or a single dose of 375 mg/m 2 , have been explored in ITP patients showing similar short-term efficacy [ 142 ]. With the clearance of rituximab from the body and the gradual recovery of B cells, most patients will relapse after 6 months.…”