Avatrombopag for severe refractory thrombocytopenia in a pediatric patient with ALL following allogeneic hematopoietic stem cell transplantation: A case report

Patients who receive allogeneic hematopoietic stem cell transplantation (alloHSCT) are at risk for developing persistent thrombocytopenia. Here, we describe treatment with avatrombopag, a thrombopoietin receptor agonist, in a pediatric patient with chronic, severe, transfusion-dependent thrombocytopenia (<10 × 10³/µL) post-alloHSCT that was persistent despite treatment with romiplostim, another thrombopoietin receptor agonist. Following the granting of a compassionate use investigational new drug authorization, avatrombopag treatment was initiated, and the patient's platelet count increased. To date, the patient has maintained a platelet count >100 × 10³/µL. No adverse events or medication toxicities have been reported, and he has resumed his pre-alloHSCT activities.