Efficacy of Eltrombopag in Children with Post-Stem Cell Transplant Prolonged Isolated Thrombocytopenia

Prolonged isolated thrombocytopenia (PIT) is a complication following allogeneic hematopoietic cell transplantation that results in prolonged transfusion dependence. Recently, the efficacy of a thrombopoietin receptor agonist (eltrombopag) against PIT has been reported in adults; however, there are few reports in children. A 4-year-old male pediatric patient diagnosed with congenital pure red cell aplasia underwent allogeneic hematopoietic cell transplantation. Neutrophil engraftment was observed on post-transplant Day 26; however, platelet counts remained <10 x 10(9)/L. Transfusions were required 1-2 times a week for at least 4 months. On post-transplant Day 124, oral eltrombopag (up to 2.4 mg/kg/day) was initiated. Thereafter, the platelet counts were maintained at >= 10 x 10(9)/L, and the patient became transfusion independent. At 2 years and 6 months after the oral administration, no chromosomal abnormalities, thromboembolism, or myelofibrosis was observed. Thus, eltrombopag can be a potential treatment option for pediatric PIT.