Abstract
Gemtuzumab ozogamicin (Mylotarg®, GO) was approved for the treatment of relapsed and refractory CD33+ acute myeloid leukemia (AML) in Japan in 2005. The optimal therapeutic regimen of GO for childhood AML, however, has not been established. Here, we present the cases of four patients with pediatric refractory AML treated with fractionated GO monotherapy (9 mg/m2 divided into three doses). Two patients achieved complete remission. Two patients developed Grade 2 infusion reactions and no patient developed veno-occlusive disease (VOD) during the fractionated GO monotherapy. Although all four patients had Grade 3 infection, no patient had other severe nonhematological toxicities. All four patients underwent subsequent HSCT after the fractionated GO monotherapy and three patients relapsed. Although there was no treatment-related mortality, VOD occurred in two patients as a complication after HSCT. Even with fractionated GO monotherapy, which can lessen the toxicity of GO, we need to be cautious of infections and VOD after HSCT.
