This study involves an experimental drug called quizartinib, which is not yet approved for regular use and is being tested for its safety and effectiveness in children and young adults with a blood cancer called Acute Myeloid Leukemia (AML). To join, participants must have a specific type of AML that hasn't responded to treatment or has come back after getting better.

The study has several phases:

• Dose Escalation/De-escalation: This phase determines the right dose of quizartinib for different age groups.
• Dose-Expansion: Here, participants receive the determined dose for their age group.
• Continuation Therapy: Participants in remission may continue quizartinib for up to 12 cycles.

Key points:

• The study involves multiple phases and may last several years with regular follow-ups.
• Participants will receive quizartinib along with other treatments and may undergo a stem cell transplant.
• Risks include side effects of quizartinib and other treatments, which will be monitored by a committee of experts.