Lenalidomide in Acute Leukemias and Chronic Lymphocytic Leukemia.

Rationale: Lenalidomide has properties of thalidomide and appears to have some activity against cancer in laboratory tests. Researchers are still learning how lenalidomide works against cancer in patients. Some ways that this drug seems to produce anti-cancer effects include through stimulating the immune system and blocking blood vessels contributing to cancer growth. The current study will explore different dose levels in patients to gather more information about lenalidomide. Purpose: This study will assess the maximum tolerated dose of lenalidomide in patients with relapsed or refractory acute leukemias and chronic lymphocytic leukemias. Toxicity or side effects within patients will also be evaluated. Other purposes of this study include analyzing preliminary clinical activity, pharmacokinetics, and pharmacodynamics. Pharmacokinetics refers to the activity of drugs in the body over a period of time, including how drugs are absorbed, distributed, localized in tissues, and excreted. Pharmacodynamics refers to the bodily processes that lead the drug to effect cancer and other cellular components in the body. Treatment: Study participants will be given lenalidomide through intravenous infusions once every 28 days. A 28-day period constitutes a cycle. Since this study will assess the maximum tolerated dose of lenalidomide, some study participants will receive different amounts of this drug compared to others depending upon when each individual enrolls in the study. Each group of 3 to 6 study participants will receive a higher dose of lenalidomide until the maximum tolerated dose is established. Several tests will be performed throughout the study, including bone marrow biopsies. Imaging exams will be conducted as well. Treatments will be discontinued due to disease growth or intolerable adverse effects. Lenalidomide administration will be repeated for 12 or more cycles in patients that experience clinical benefit.