Inclusion Criteria:

- Diagnosis of relapsing/refractory or previously untreated chronic lymphocytic
leukemia

- Eastern Cooperative Oncology Group (ECOG) performance score of >/=1

- Adequate bone marrow function

- Adequate renal and hepatic function

Exclusion Criteria:

- Patient received an allogeneic stem cell transplant

- Infection with human immunodeficiency virus, hepatitis B, or hepatitis C

- Uncontrolled autoimmune hemolytic anemia or thrombocytopenia

- Investigational or anti-cancer therapy within 14 days of study start

- History of significant renal, neurologic, psychiatric, endocrinologic, metabolic,
immunologic, cardiovascular, or hepatic disease