The overall and progression-free survival rates in children with relapsed or refractory acute myeloid leukemia remain poor. Venetoclax is a BCL-2 inhibitor that has shown promising outcomes when used in combination with low-dose cytarabine. Idarubicin is an anthracycline antileukemic drug that may or may not show positive outcomes when used with venetoclax–cytarabine. This study aims to compare the effectiveness of venetoclax–cytarabine with or without idarubicin. 

This is a phase-1, dose-escalation study conducted across three research hospitals in the US. The study included a total of 38 patients aged 2-22 years with relapsed or refractory acute myeloid leukemia. The participants received an elevated dose of venetoclax–cytarabine combination with or without intravenous idarubicin. The primary outcome was the safety and efficacy of the idarubicin combination. 

Out of the patients treated with the recommended phase-2 combination dose, 70% showed complete response with or without complete hematological recovery. 10% of the patients showed a partial response. The most common grade-3 & 4 adverse events were febrile neutropenia, invasive fungal infections, and bloodstream infections. One treatment-related death was reported, with the cause of death being sepsis and colitis.

The research concluded that venetoclax–cytarabine combination with intravenous idarubicin showed improved safety and efficacy in patients with relapsed and refractory acute myeloid leukemia.