Inclusion Criteria:

   1. FOR TREATMENT-NAIVE GROUP ONLY: Men and women ≥ 65 years of age with confirmed
   diagnosis of CLL/SLL, who require treatment per NCI or International Working Group
   guidelines 15-18

   2. FOR RELAPSED/REFRACTORY GROUP ONLY: Men and women ≥ 18 years of age with a confirmed
   diagnosis of relapsed/refractory CLL/SLL following previous therapy(ie, failed ≥ 2
   previous treatments for CLL/SLL and at least 1 regimen had to have had a purine analog
   [eg, fludarabine] for subjects with CLL)

   3. FOR HIGH-RISK RELAPSED/ REFRACTORYGROUP ONLY: Men and women ≥ 18 years of age with a
   confirmed diagnosis of relapsed/refractory CLL/SLL with suboptimal response to
   chemoimmunotherapy, defined as progression of disease within 24 months of initiation
   of a regimen containing at least a nucleoside analogue or bendamustine in combination
   with a monoclonal antibody or failure to respond to such a regimen. (Note: a minimum
   of 2 cycles of chemoimmunotherapy required for eligibility)

   4. ECOG performance status of ≤ 2

   5. Willing and able to participate in all required evaluations and procedures in this
   study protocol including swallowing capsules without difficulty

Exclusion Criteria:

   1. Prior malignancy, except for adequately treated basal cell or squamous cell skin
   cancer, in situ cervical cancer, or other cancer from which the subject has been
   disease free for at least 2 years or which will not limit survival to < 2 years

   2. Any immunotherapy, chemotherapy, radiotherapy, or experimental therapy within 4 weeks
   before first dose of study drug (corticosteroids for disease-related symptoms allowed
   but require 1-week washout before study drug administration)

   3. Central nervous system (CNS) involvement by lymphoma

   4. Major surgery within 4 weeks before first dose of study drug

   5. Concomitant use of medicines known to cause QT prolongation or torsades de pointes

   6. Significant screening electrocardiogram (ECG) abnormalities including left bundle
   branch block, 2nd degree AV block type II, 3rd degree block, bradycardia, and QTc >
   470 msec

   7. Lactating or pregnant