Romiplostim therapy in children with unresponsive chronic immune thrombocytopenia

Romiplostim, a thrombopoiesis-stimulating peptibody, represents a new therapeutic option in adult refractory chronic immune thrombocytopenia (ITP). This study aimed to assess the short-term efficacy and safety of romiplostim in children with chronic ITP. Eight non-splenectomized patients with chronic ITP refractory to standard lines of medical therapy were recruited from the Pediatric Hematology Unit, Children's Hospital, Ain Shams University, Cairo, Egypt. One patient was initially excluded because of increased bone marrow reticulin (grade 3). Therapy was initiated in seven patients, aged 3.4-15.2 years (median 5.5 years), and the disease duration ranged from 13 months to 7.3 years (median 2.4 years); none were splenectomized. Romiplostim dose was started as 1 mu gm/kg/week and the dose escalated by 1 mu gm/kg/week according to platelet count. The duration of therapy varied between 1 and 22 weeks (median 12 weeks). Results revealed that four out of the seven patients achieved variable response. Four patients demonstrated rapid increase in platelet count when pulse steroid therapy was added. Most reported adverse events were mild and transient. This case series study reveals variable response rate in children with chronic ITP to romiplostim therapy; addition of steroids especially in emergency bleeding situations could potentiate romiplostim thrombopoietic effect even in patients initially refractory to steroids. Romiplostim safety and efficacy in pediatric ITP needs further long-term studies.