A Phase II Study of Ibrutinib Plus FCR in Previously Untreated, Younger Patients With Chronic Lymphocytic Leukemia

This research study is evaluating a new drug called ibrutinib in combination with the standard drugs fludarabine, cyclophosphamide, and rituximab (FCR) as a possible treatment for Chronic Lymphocytic Leukemia (CLL).

Inclusion Criteria: * Must have a confirmed diagnosis of chronic lymphocytic leukemia or small lymphocytic lymphoma. as per IW-CLL 2008 criteria. Patients must also require therapy for that diagnosis, based on meeting at least one of the following criteria: * evidence of progressive marrow failure as manifested by the development of, or worsening of, anemia (hemoglobin \480 ms. NOTE: This criterion does not apply to patients with a left bundle branch block. * Patients who require warfarin or other vitamin K antagonists for anticoagulation (other anticoagulants are allowed after consultation with the Principal Investigator). * Concurrent administration of medications or foods that are strong inhibitors or inducers of CYP3A * Patients with ongoing use of prophylactic antibiotics are eligible as long as there is no evidence of active infection and the antibiotic is not included on the list of prohibited medications * Significant co-morbid condition or disease which in the judgment of the Principal Investigator would place the patient at undue risk or interfere with the study * Unable to receive prophylactic treatment for pneumocystis * Patients with del(17p) confirmed by FISH in ≥20% of cells or on stimulated karyotype3.2.24 Patients with del(17p) confirmed by FISH in ≥20% of cells or on stimulated karyotype * Patients with unmutated IGHV who also have a complex karyotype on a stimulated karyotype