A Study of Venetoclax in Combination With Chemotherapy to Treat Newly Diagnosed Acute Lymphoblastic Leukemia (ALL)

All patients will complete Induction I and II of the treatment regimens, consisting of several chemotherapy agents including Peg-ASP. * For Dose Level 1: Venetoclax will be administered at a dose of 100mg on day 5, 200mg on day 6 and 400mg on days 7-28 during Induction I. During Induction II, venetoclax will be administered at 400mg daily from days 1-14 and 29-42. * For Dose Level -1: Venetoclax will be administered at a dose of 100mg on day 5 and 200mg on days 6-28 during Induction I. During Induction II, venetoclax will be administered at 200mg daily from days 1-14 and 29-42. * Bone marrow aspirate and biopsy will be performed at day 14 of Induction I, after Induction I and Induction II for disease assessment. For those who remain on study after Induction II, they will proceed to consolidation therapy. Consolidation blocks contain 2 Intensification blocks (22 days each) and 2 Re-Induction blocks (43 days each), consisting of several chemotherapy agents including Peg-ASP. * Venetoclax will be administered at a dose of 400mg daily (Dose Level 1) or 200mg daily (Dose Level -1) from days 1-22 during Intensification blocks, and from days 1-14 and 29-42 during Re-Induction blocks. * Bone marrow aspirate and biopsy will be performed after Re-Induction I and Re-Induction II for disease assessment. * Patients who relapse either with MRD or morphologically will be removed from study to pursue alternative therapy. * Patients who remain in MRD negative CR will remain on study and proceed to Maintenance. * Maintenance block contains 4-drug regimen (vincristine, oral methotrexate, oral mercaptopurine, and prednisone) for 2 years. No venetoclax will be administered during this block. Bone marrow aspirate and biopsy will be performed every 3 months during the Maintenance block. Patients who remain in MRD negative CR will remain on study to complete the study treatment. Patients who relapse either with MRD or morphologically will be removed from study to pursue alternative therapy.