EZN-3042 Administered With Re-induction Chemotherapy in Children With Relapsed Acute Lymphoblastic Leukemia (ALL)

Dose will be assigned at study entry. To be given as a 2 hour intravenous infusion on days -5, -2, 8, 15, 22 and 29. Dose levels: L0 (level zero): 1.5 mg/kg, L1: 2.5 mg/kg, L2: 5 mg/kg, L3: 6.5 mg/kg

"Given intrathecally on day -6. Patients who may have received intrathecal chemotherapy within 7 days of day 0 as part of their prior maintenance chemotherapy (e.g. before the diagnosis of relapse) or as part of the diagnostic workup will not receive this dose of IT cytarabine. If given, dose is defined by age:~1-1.99 years: 30 mg 2-2.99 years: 50 mg~Greater than or equal to 3 years: 70 mg.~Cytarabine is also part of the triple intrathecal therapy given to CNS 3 patients on Days 8, 15, 22 and 29. Dose is defined by age:~1. \- 1.99 years: 16 mg~2. \- 2.99 years: 20 mg~3. \- 8.99 years: 24 mg~Greater than or equal to 9 years: 30 mg"

60 mg/m2/day given intravenous infusion (IV) over 15 minutes on day 1.

40 mg/m2/day divided BID or TID given orally on days 1 through 29. For patients who are unable to tolerate prednisone orally, substitute IV methylprednisolone at 80% of the oral prednisone dose.

1.5 mg/m2/day (maximum dose 2 mg) given intravenous push over 1 minute or infusion via mini-bag as per institutional policy on days 1, 8, 15 and 22.

2500 IU/m2 intramuscular injection on days 2, 9, 16, 23. If available, Erwinia L-asparaginase may be substituted for pegaspargase in patients with clinically significant prior allergies to pegaspargase.

"Given intrathecally to patients with CNS1 or CNS2 disease at the dose defined by age below on days 15 and 36:~1-1.99 years: 8 mg 2-2.99 years: 10 mg 3-8.99 years: 12 mg~Greater than or equal to 9 years: 15 mg~Given as part of the Triple intrathecal therapy to patients with CNS 3 disease at the doses defined by age below on days 8, 15, 22 and 29:~1. \- 1.99 years: 8 mg~2. \- 2.99 years: 10 mg~3. \- 8.99 years: 12 mg~Greater than or equal to 9 years: 15 mg"

"Given as part of the Triple intrathecal therapy to patients with CNS 3 disease at the doses defined by age below on days 8, 15, 22 and 29:~1. \- 1.99 years: 8 mg~2. \- 2.99 years: 10 mg~3. \- 8.99 years: 12 mg~Greater than or equal to 9 years: 15 mg"