Rituximab or cyclosporin in refractory immune thrombocytopenia secondary to connective tissue diseases: a real-world observational retrospective study

Immune thrombocytopenia (ITP) is a common complication of connective tissue diseases (CTD). However, refractory and recurrent cases are frequent, who often need intensive immunotherapy. In the real world to compare the efficacy and safety of two common options, rituximab (RTX) and cyclosporine (CsA), in patients with refractory CTD-ITP, we conducted this retrospective study. Inpatients diagnosed with CTD-ITP who experienced treatment failure with initial prednisone or other immunosuppressants and who subsequently received either RTX or CsA between 2013 and 2018 were identified. All the patients were followed up for at least 6 months. Remission was defined as sustained platelet count ≥ 50 × 10^9/L, where ≥ 100 × 10^9/L was considered complete remission and 50–100 × 10^9/L was considered partial remission. Propensity score weighting analysis was performed to balance the confounders as indication. A total of 83 patients with CTD-ITP were identified, of whom 43 had systemic lupus erythematosus, 24 had undifferentiated CTD, and 16 had primary Sjogren syndrome. The RTX group ( n = 53) had a much higher remission rate than the CsA group ( n = 30) after 3 months and throughout the following 3 months (3 m, 86.8% vs 63.6%, p = 0.025; 6 m, 81.8% vs 53.5%, p = 0.011). Binary logistic regression analysis confirmed that treatment with RTX predicted better outcome (OR 4.09, 1.42 ~ 11.79), while age > 50 (OR 0.31, 0.11 ~ 0.93) was a risk factor. Furthermore, we reinforced the conclusions by propensity score weighting analysis (RTX OR 4.89, 1.64 ~ 14.58; age > 50 OR 0.31, 0.12 ~ 0.83). In our real-world retrospective study, for patients with refractory CTD-ITP, RTX was superior to CsA in terms of the durable remission rate. Key Points: • Refractory cases are common in patients with immune thrombocytopenia secondary to connective tissue diseases (CTD-ITP), requiring intensive immunotherapy. • Randomized controlled trials comparing rituximab and a traditional immunosuppressive agents (IS), such as cyclosporin, are lacking in these patients. • Our real-word retrospective study indicated that rituximab was superior to cyclosporin in patients with refractory CTD-ITP.