A Phase 2 Open-Label Study of the Efficacy and Safety of ABT-199 (GDC-0199) in Chronic Lymphocytic Leukemia (CLL) Subjects With Relapse or Refractory to B-Cell Receptor Signaling Pathway Inhibitor Therapy

Inclusion Criteria:

   - Participant must have a diagnosis of chronic lymphocytic leukemia (CLL) that meets
   2008 Modified International Workshop on Chronic Lymphocytic Leukemia National Cancer
   Institute-Working Group (IWCLL NCI-WG) criteria

   - Participant has relapsed/refractory disease with an indication for treatment

   - Participant has refractory disease or developed recurrence after therapy with a B-cell
   receptor pathway inhibitor (BCR PI)

   - Participant must have an Eastern Cooperative Oncology Group performance score of ≤ 2

   - Participant must have adequate bone marrow function at Screening

   - Participant must have adequate coagulation profile, renal, and hepatic function, per
   laboratory reference range at Screening

Exclusion Criteria:

   - Participant has undergone an allogeneic stem cell transplant within the past year

   - Participant has developed Richter's transformation confirmed by biopsy

   - Participant has active and uncontrolled autoimmune cytopenia

   - Participant has malabsorption syndrome or other condition that precludes enteral route
   of administration

   - Participant is human immunodeficiency virus (HIV) positive or has chronic hepatitis B
   or hepatitis C virus requiring treatment

   - Participant has known contraindication or allergy to both xanthine oxidase inhibitors
   and rasburicase