Patient demographics and clinical characteristics
Fifteen pediatric and young adult patients with hematological malignancies who received a TPO-RA were included in this case series(Table 1). The cohort consisted of nine females and six males, with a median age of 16 years (range: 7-25 years). Diagnoses included a range of hematologic malignancies. Seven patients had undergone a prior HSCT. Patients received a TPO-RA during a variety of phases of therapy, including initial induction, consolidation, delayed intensification, re-induction following relapse, following CAR T-cell therapy and post-HSCT. Ten patients (67%) had disease in remission at the time of receiving a TPO-RA.
In 14 patients (93%), a TPO-RA was initiated due to thrombocytopenia refractory to platelet transfusions. Nine patients (60%) had an additional comorbidity that placed them at very high risk of bleeding or refractory thrombocytopenia, including angioinvasive fungal infections (n=3), history of retinal hemorrhages (n=2), brain abscess (n=1), transplant-associated thrombotic microangiopathy and respiratory infections with associated hemoptysis (n=2), and hemorrhagic cystitis secondary to BK viremia (n=1). One patient was a Jehovah’s Witness who received romiplostim prophylactically to minimize transfusions. One patient had refractory thrombocytopenia secondary to human leukocyte antigen alloimmunization.