Safety and Efficacy of Avapritinib in Relapsed or Refractory Pediatric CBF-AML With KIT Mutation

This study tests a targeted drug called avapritinib in children with a type of leukemia (blood cancer) called AML that has come back or stopped responding to treatment. AML is a cancer of the blood and bone marrow, and this trial focuses on a specific type that has certain genetic changes (CBF-AML with a KIT mutation). **You may be eligible if...** - You are under 18 years old - You have been diagnosed with acute myeloid leukemia (AML) with specific genetic features (t(8;21) or inv(16) and a KIT mutation) - Your AML did not respond to standard treatment, or it came back after remission - You have no active infections - Your liver and kidney function are in an acceptable range - You are generally well enough to participate (ECOG score under 2) - Your expected survival is more than 12 weeks **You may NOT be eligible if...** - You have already received avapritinib - You are currently taking other targeted leukemia drugs (e.g., dasatinib, sorafenib, venetoclax) - You have an uncontrolled active infection - You have serious heart, liver, or kidney disease - You have another cancer requiring treatment - You are already enrolled in another interventional clinical trial Talk to your doctor to see if this trial is right for you.