A Prospective Trial of Dalbavancin-Based Prophylaxis in Children and Adolescents With High-Risk Leukemia

Inclusion Criteria: * Aged less than or equal to 25 years at enrollment * Receiving treatment for AML or relapsed ALL at St. Jude and treatment is expected to cause prolonged (\> 7 days) severe neutropenia (ANC \< 500/ml) * Expected to receive care at St. Jude for at least 56 days following enrollment on the protocol * Female participant, greater than or equal to 9 years old, has a documented negative pregnancy test prior to receipt of study drug. Exclusion Criteria: * Allergy to vancomycin, dalbavancin, teicoplanin, levofloxacin or ciprofloxacin (Not including non-anaphylactic vancomycin infusion reaction) * Documented past or current infection or colonization with pathogenic bacteria resistant to vancomycin plus either ciprofloxacin or levofloxacin * Diagnosed with long QT syndrome * Any condition judged by the investigator to put the participant at high risk from participation * Suspected or proven active bacterial infection * Inability to complete requirements of participation in the study (in the opinion of the investigator) * Expected survival \<28 days * Alkaline phosphatase, alanine transferase or total bilirubin ≥ 3x upper limit of normal for age * Estimated glomerular filtration rate (EGFR) \<30 mL/minute/1.73 m2 * Other absolute contraindication to administration of fluoroquinolone antibiotics or dalbavancin * Participant is pregnant or breastfeeding a child