Clinical/Molecular Risk-Tailored Intensive, Compressed Induction Chemotherapy Followed by Consolidation Randomization To Single-Cycle or 3 Tandem Cycles of Marrow-Ablative Chemo with Hematopoietic Progenitor Cell Rescue | Head-Start-4 | NCT02875314 Phase 4 | Next Consortium, Nationwide Children's | Caroline Hastings, MD | Effie Bourgin |