Nivolumab in Combination With 5-azacytidine in Childhood Relapsed/Refractory AML

This proposed study will be the first to test nivolumab in combination with AZA in pediatric patients with hematologic malignancies. Patients will receive the first dose of nivolumab on day 1 along with AZA. After "chemotherapy priming", a second dose of nivolumab will be given at day 15 which will enhance the effect of nivolumab on the regenerating CD4+ and CD8+ memory T cells. To establish a recommended Phase II dose (RP2D)of nivolumab in combination with 5-azacytidine in children with relapsed or refractory AML. To assess the clinical activity of Nivolumab in combination with 5-azacytidine in AML patients with M2/M3 disease at study entry.