Prevention of Invasive Fungal Infections (IFIs) in Subjects Receiving Chemotherapy for Acute Lymphoblastic Leukemia

Inclusion Criteria: * Newly diagnosed ALL receiving an ALL chemotherapy regimen that typically induces at least 10 days of neutropenia defined as an absolute neutrophil count \< 500 cells/mm\^3 or 0.5 × 10\^9 cells/L * Subjects with lymphoblastic lymphoma or any malignancy other than ALL are NOT eligible for this study. * Age ≥ 18 years * Able to have all screening tests performed quickly to ensure results can be obtained and evaluated before randomization so that the first dose of randomized study drug for IFI prophylaxis can be administered within 5 days of first remission-induction chemotherapy * Preremission induction treatment (ie, pre-phase) with a minimally or nonmyelosuppressive regimen for up to one week is not considered to constitute the beginning of remission induction chemotherapy * Ability to understand and sign a written informed consent form, which must be obtained prior to initiation of any study procedures Exclusion Criteria: * Known hypersensitivity to amphotericin B or AmBisome, the metabolites or formulation excipients, in particular known history of anaphylactic reaction to amphotericin B or AmBisome or any of its metabolites or formulation excipients * Known hypersensitivity to the excipients of the placebo formulation * Current fever (≥ 38°C) unless explained by noninfectious causes * Subjects with proven, probable or possible IFI (according to European Organization for the Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria) at screening or in subject history * Pulmonary infiltrates * Concomitant or previous treatment with an antifungal drug within the previous 30 days unless the plasma level is below the limit of detection or at least 5 half-lives of the antifungal has elapsed since the treatment was given * Serum creatinine \> 2 × the upper limit of the normal range (ULN) * Grade 3 Liver function test results: alanine aminotransferase or aspartate aminotransferase \> 5 × ULN; total bilirubin \> 2.5 x ULN * Any severe co morbidity other than underlying hematological disease (ALL), which in the investigator's judgment may interfere with study evaluations or affect the subject's safety * Subjects who have taken any investigational drug in the last 30 days prior to screening, with the exception of ALL chemotherapy investigational products being used as part of the subject's current ALL treatment protocol * Pregnant or nursing females * Subjects with a prior history of a malignancy that was treated with a myeloablative chemotherapy regimen are NOT eligible for this study.