Intravenous Erwinia Chrysanthemi Asparaginase in Patients With Newly Diagnosed Philadelphia Chromosome Negative Acute Lymphoblastic Leukemia Aged 60 Years or Older

The study consists of three treatment phases. 1. Steroid prophase (days -3 to -1): To prevent rapid leukemia progression and reduce tumor load, patients will receive either prednisone 60mg/m2 oral daily or equivalent corticosteroid daily for 3 days. 2. Asparaginase phase (days 1 - 14): Patients will receive Erwinia asparaginase 25,000 IU/m2 IV three times a week on a Monday, Wednesday, Friday (MWF) schedule for 2 weeks. Patients are permitted to begin Erwinia asparaginase on Monday, Wednesday, or Friday, so that their schedules are defined as MWF, WFM, or FMW. For rapid progression of disease (defined by rising WBC \>30K with \> 50% peripheral blasts), prednisone 60mg/m2 oral daily or equivalent corticosteroid daily may be added. Bone marrow aspirate and/or biopsy will be performed on days 13-15 of the asparaginase treatment for early disease response assessment. 3. Chemotherapy phase (days 15 - 42): * Cyclophosphamide 650 mg/m2 IV on day 15 * Vincristine 1.4 mg/m2 (max 2mg) IV on days 15, 22, 29, and 36 * Prednisone 60mg/m2 (or equivalent corticosteroid) oral daily for 28 days on days 15 - 42 * Erwinia asparaginase 25,000 IU/m2 IV three times a week on a MWF schedule for 2 weeks on days 29 - 42 (after a two week interval without Erwinia asparaginase administered on days 1 - 14) Upon cell count recovery, a bone marrow aspirate and/or biopsy will be performed to assess the disease response. Subsequent treatments following the bone marrow evaluation will be left up to the discretion of the treating physicians. If the first 6 patients have no response or progress during the 2 weeks of asparaginase phase of treatment with or without steroid, the next 6 patients will start directly with the chemotherapy phase (days 15-42) of treatment consisting of cyclophosphamide, vincristine, and prednisone with Erwinia asparaginase. CNS prophylaxis: * IT methotrexate 12mg (flat dose) between days 15 - 22 * IT methotrexate 12mg (flat dose) between days 22- 29 * There will be a minimal interval between doses of 7 days