Inclusion Criteria:

• Diagnosis of ALL (any type included), in patients who:

  • have relapsed after conventional chemotherapy* or,
  • are refractory to at least 1 cycle of chemotherapy*
• ECOG Performance score of 0-3
• Adequate hepatic and renal function, as defined by serum transaminases <2.5x ULN, bilirubin <1.5xULN, and creatinine <1.5x ULN.
• Age 18 years or greater.
• Documentation of written informed consent to participate in the trial.
• Willingness and ability to comply with scheduled visits, treatment plan, laboratory tests and other study procedures.
• at least 3 weeks from prior chemotherapy or other investigational anticancer therapy with full recovery from prior toxicities.
• either men or women, accepting to practice effective contraception during the entire study period unless documentation of infertility exists.

Exclusion Criteria:

• Treatment with any investigational agent within 3 weeks prior to study therapy.
• Major surgeries within 4 weeks from study start or not fully recovered from any previous surgical procedure.

• Presence of any medical or psychiatric condition which may limit full compliance with the study or increase the risk associated with study participation or study drug administration, including but not limited to:

  • Presence of central nervous system (CNS) leukemia.
  • Active uncontrolled bacterial infection.
  • Known human immunodeficiency virus (HIV) infection.
  • Significant cardiovascular disease (i.e., uncontrolled arrhythmias, unstable angina), or a major thromboembolic event (myocardial infarction, stroke, transient ischemic attack, pulmonary embolism, or non-catheter-related deep-vein thrombosis) in the last 6 months.
  • Pregnancy or breast-feeding.
  • Malabsorption syndromes