Inclusion Criteria:

• Diagnosis of chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) that meets protocol-defined criteria
• Active disease meeting at least 1 of the International Workshop on Chronic Lymphocytic Leukemia 2008 criteria for requiring treatment
• Measurable nodal disease by computed tomography
• Relapsed or refractory CLL or SLL following at least 1 prior line of systemic therapy consisting of at least 2 cycles of a chemotherapy-containing regimen
• Eastern Cooperative Oncology Group Performance Status score of 0 or 1
• Hematology and biochemical values within protocol-defined limits
• Agrees to protocol-defined use of effective contraception
• Women of childbearing potential must have negative blood or urine pregnancy test at screening

Exclusion Criteria:

• Recent therapeutic interventions within 3 (chemotherapy/radiotherapy) to 10 weeks (immunotherapy)
• Prior treatment with ibrutinib or other Bruton's tyrosine kinase inhibitors or prior randomization in any other clinical study evaluating ibrutinib
• The presence of deletion of the short arm of chromosome 17
• Patients previously treated with a bendamustine-containing regimen who did not achieve a response or who relapsed and required treatment within 24 months of treatment with that regimen
• Patients for whom the goal of therapy is tumor debulking prior to stem cell transplant
• Received a hematopoietic stem cell transplant
• Known central nervous system leukemia/lymphoma or Richter's transformation
• Patients with uncontrolled autoimmune hemolytic anemia or autoimmune thrombocytopenia
• Chronic use of corticosteroids
• History of prior malignancy, except: malignancy treated with curative intent and with no known active disease present for ≥3 years before randomization; adequately treated non-melanoma skin cancer or lentigo maligna without evidence of disease; adequately treated cervical carcinoma in situ without evidence of disease
• History of stroke or intracranial hemorrhage within 6 months prior to randomization; or clinically significant cardiovascular disease
• Requires anticoagulation with warfarin or equivalent vitamin K antagonists or treatment with strong CYP3A4/5 inhibitors
• Known history of human immunodeficiency virus or hepatitis C, or active infection with hepatitis B or C
• Any uncontrolled active systemic infection or any life-threatening illness, medical condition, or organ system dysfunction which, in the investigator's opinion, could compromise the patient's safety, interfere with the absorption or metabolism of ibrutinib capsules, or put the study outcomes at undue risk
• A woman who is pregnant or breast feeding, or a man who plans to father a child while enrolled in this study or within 3 months after the last dose of study drug