Efficacy and Safety of the Combination Treatment of Rituximab and Dexamethasone for Adults with Primary Immune Thrombocytopenia (ITP): A Meta-Analysis

Abstract

Objective. To conduct a meta-analysis, assessing the efficacy and safety of the combination treatment of dexamethasone and rituximab for adults with ITP (primary immune thrombocytopenia). Methods. Randomized controlled trials that compared rituximab and dexamethasone combination treatment to dexamethasone monotherapy in the treatment of adults with ITP were collected by searching Pubmed, Embase, Cochrane, China National Knowledge (CNKI), Wanfang database, and Sino Med. We conducted pooled analyses on OR (overall response) rate, CR (complete response) rate, PR (partial response) rate, SR (sustained response) rate, R (relapse) rate, change in Treg cell count (mean [SD]), and AE (adverse event). GRADE pro scale was used to assess the quality of the evidence. Publication bias was assessed with Egger's test method. Results. A total of 11 randomized controlled trials were eligible for inclusion. The overall efficacy estimates favored combination arm in terms of OR rate at month 3, CR rate at week 4 and month 3, SR rate, and Treg cell count at week 2. Subgroup analysis showed that females obtained a higher OR rate than males did at week 4. No significant difference was found in pooled analysis of relapse rate between combination arm and monotherapy arm. The comparison of serious AE and other AEs showed no significant difference either. A total of 19 outcomes were assessed by GRADE pro software, of which 79% (15/19) was scaled as moderate-to-high level. Publication bias existed in studies on OR at week 4 (P=0.025), CR at week 4 (P=0.017), infection (P=0.006), and rash (P=0.028) of the AEs. Conclusion. Dexamethasone combined with rituximab can provide a better long-term response in the treatment of adults with ITP and will not increase the risk of adverse effects.

Figure 1

Flow diagram of studies selection process. ITP, primary immune thrombocytopenia.

Figure 2

Forest plots of relative risk in OR rate. (a) OR rate at week 4; (b) subanalysis based on gender; (c) subanalysis based on treatment history; (d) OR rate at month 3. CI: confidence interval; M-H: Mantel-Haenszel; RR: relative risk.

Figure 3

Forest plots of relative risk in CR rate. (a) CR rate at week 4; (b) CR rate at month 3. CI: confidence interval; M-H: Mantel-Haenszel; RR: relative risk.

Figure 4

Forest plots of relative risk in PR rate at week 4. CI: confidence interval; M-H: Mantel-Haenszel; RR: relative risk.

Figure 5

Forest plots of relative risk in SR rate. (a) SR at month 6; (b) SR at month 12. CI: confidence interval; M-H: Mantel-Haenszel; RR: relative risk.

Figure 6

Forest plots of MD in Treg cell count. (a) Treg cell count at week 2; (b) Treg cell count at week 4. CI: confidence interval; IV: Inverse Variance; MD: Mean Difference.

Figure 7

Funnel plots of publication bias. (a) publication bias of OR rate at week 4; (b) publication bias of CR rate at week 4; (c) publication bias of incidence in infection; (d) publication bias of incidence in rash.