Single Agent Lenalidomide in Adult Patients With Relapsed/Refractory Acute Lymphoblastic Leukemia

Inclusion Criteria: * Relapsed or refractory acute lymphoblastic leukemia (ALL) with \> 10% bone marrow or peripheral blood blasts per WHO-criteria. Refractory define as failure to achieve CR after prior therapy. * Previously untreated patients \> 60, if not candidates for standard induction * Age ≥ 18 * Not a candidate for curative treatment regimens * Unwilling or unable to receive conventional chemotherapy * ECOG performance status ≤ 2 * Life expectancy \> 2 months * Registered to in RevAssist restricted distribution program, and willing and able to comply with the program requirement * Females of childbearing potential (FCBP): * Must have a negative serum or urine pregnancy test (sensitivity of at least 50 mIU/mL) 10 to 14 days prior to study enrollment and within 24 hours prior to prescribing lenalidomide * Must either commit to continued abstinence from heterosexual intercourse or begin two acceptable methods of birth control * Agree to ongoing pregnancy testing * Men must agree to use a latex condom during sexual contact with a FCBP * Able to adhere to the study visit schedule and other protocol requirements * Willing and able to understand and voluntarily sign a written informed consent Exclusion Criteria: * Prior therapy with lenalidomide * History of intolerance to thalidomide including development of erythema nodosum while taking thalidomide or similar drugs * Advanced malignant hepatic tumors. * Concomitant treatment with other anti-neoplastic agents (exception hydroxyurea) * Anti-neoplastic treatment less than 4 weeks prior to enrollment (exception hydroxyurea) * Use of any other experimental drug or therapy within 14 days of baseline * Inability to swallow or absorb drug * Active opportunistic infection or treatment for opportunistic infection within 4 weeks of first dose of study drug * New York Heart Association Class III or IV heart failure * Unstable angina pectoris * Cardiac arrhythmias with rapid ventricular response (heart rate \> 100 beats/minute) * Uncontrolled psychiatric illness that would limit compliance with requirements * Known HIV infection * Known active hepatitis B virus (HBV) (exception seropositivity due to HBV vaccine not considered active HBV) * Known hepatitis C virus (HCV) infection * Pregnant * Lactating females must agree not to breastfeed while taking lenalidomide * Other medical or psychiatric illness or organ dysfunction or laboratory abnormality which in the opinion of the investigator would compromise the patient's safety or interfere with data interpretation * Creatinine ≥ 1.5 mg/dL * Creatinine clearance ≤ 60 mL/min. * Total bilirubin \> 1.5 x institutional upper limit of normal (ULN) (exception documented Gilbert's syndrome) * AST and ALT \> 3 x institutional ULN