Gemtuzumab Ozogamicin in Children and Adolescents With De Novo Acute Myeloid Leukemia Improves Event-Free Survival by Reducing Relapse Risk: Results From the Randomized Phase III Children’s Oncology Group Trial AAML0531
Mené sur 1 002 jeunes patients atteints d'une leucémie myéloïde aiguë récemment diagnostiquée, cet essai de phase III évalue l'efficacité, du point de vue de la survie sans événement et de la survie globale, et la toxicité de l'ajout de gemtuzumab ozogamicine à une chimiothérapie de référence
Purpose : To improve survival rates in children with acute myeloid leukemia (AML), we evaluated gemtuzumab-ozogamicin (GO), a humanized immunoconjugate targeted against CD33, as an alternative to further chemotherapy dose escalation. Our primary objective was to determine whether adding GO to standard chemotherapy improved event-free survival (EFS) and overall survival (OS) in children with newly diagnosed AML. Our secondary objectives examined outcomes by risk group and method of intensification. Patients and Methods : Children, adolescents, and young adults ages 0 to 29 years with newly diagnosed AML were enrolled onto Children’s Oncology Group trial AAML0531 and then were randomly assigned to either standard five-course chemotherapy alone or to the same chemotherapy with two doses of GO (3 mg/m2/dose) administered once in induction course 1 and once in intensification course 2 (two of three). Results : There were 1,022 evaluable patients enrolled. GO significantly improved EFS (3 years: 53.1% v 46.9%; hazard ratio [HzR], 0.83; 95% CI, 0.70 to 0.99; P = .04) but not OS (3 years: 69.4% v 65.4%; HzR, 0.91; 95% CI, 0.74 to 1.13; P = .39). Although remission was not improved (88% v 85%; P = .15), posthoc analyses found relapse risk (RR) was significantly reduced among GO recipients overall (3 years: 32.8% v 41.3%; HzR, 0.73; 95% CI, 0.58 to 0.91; P = .006). Despite an increased postremission toxic mortality (3 years: 6.6% v 4.1%; HzR, 1.69; 95% CI, 0.93 to 3.08; P = .09), disease-free survival was better among GO recipients (3 years: 60.6% v 54.7%; HzR, 0.82; 95% CI, 0.67 to 1.02; P = .07). Conclusion : GO added to chemotherapy improved EFS through a reduction in RR for children and adolescents with AML.