Fludarabine and Rituximab With or Without Lenalidomide or Cyclophosphamide in Treating Patients With Symptomatic Chronic Lymphocytic Leukemia

This randomized phase II trial studies how well fludarabine (fludarabine phosphate) and rituximab with or without lenalidomide or cyclophosphamide work in treating patients with symptomatic chronic lymphocytic leukemia. Drugs used in chemotherapy, such as fludarabine phosphate and cyclophosphamide, work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Monoclonal antibodies, such as rituximab, may block cancer growth in different ways by targeting certain cells. Lenalidomide may stimulate the immune system in different ways and stop cancer cells from growing. Giving fludarabine phosphate and rituximab together with lenalidomide or cyclophosphamide may be an effective treatment for chronic lymphocytic leukemia.