Dapsone therapy for refractory immune thrombocytopenia patients: a case series

BACKGROUND Dapsone has been recommended as a second-line immunosuppressive agent for patients with immune thrombocytopenia (ITP). METHODS We retrospectively analyzed the efficacy and safety of dapsone therapy in patients with ITP. RESULTS Nine ITP patients were treated with dapsone at a dose of 50-100 mg/day between May 2013 and March 2016. All patients were refractory to multiple previous treatments, with a median of 7 agents (range, 4-8), and 3 patients had undergone a previous splenectomy. The median pre-treatment platelet count was 4×109/L (range, 3-27×109/L). Only 1 patient (11.1%) responded to dapsone therapy. No severe adverse events were observed, except for 1 case of dapsone hypersensitivity syndrome. CONCLUSION Although dapsone is still useful for some patients, it may be ineffective in heavily pretreated patients with profound thrombocytopenia.