Efficacy and safety of rituximab as second-line therapy in immune thrombocytopenic purpura based on ethnicity: A descriptive study among the Arabic population.

BACKGROUND: Rituximab is used as second-line therapy in patients with immune thrombocytopenic purpura (ITP) who do not respond to first-line management. The response rate for Rituximab is variable in different populations ranging from 30% to 90%. The adverse effects of rituximab in patients with ITP range from infusion site reactions to the reactivation of hepatitis B virus and progressive multifocal leukoencephalopathy and interpopulation variation. METHODS: We conducted a single-center, retrospective study in Qatar's National Center for Cancer Care & Research. The study included patients with chronic refractory ITP who received rituximab as second-line therapy. Descriptive and summary statistics were used to describe the sociodemographic parameters of the study cohort. RESULTS: Of the 41 patients with chronic ITP, 26 were Arabs, 12 were Asians, and 3 were of other ethnicities. Rituximab was associated with an overall response rate of 80.4%. Arabic patients had the highest clinical response (84.6%) among the ethnicities with the lowest adverse effects (11.5%). Asians had a response rate of 66.6%, and adverse effects were seen in 16.7% of the patients. CONCLUSIONS: In chronic refractory ITP, rituximab appears to have a better clinical response in the Arabic population with minimal toxicity than in other ethnicities.