Inclusion Criteria:

1. CD20+ B-cell chronic lymphocytic leukemia (B-CLL) or small lymphocytic lymphoma
according to NCI criteria (see Appendix B).

2. Previously untreated CLL or small lymphocytic lymphoma (SLL).

3. Patients must require treatment according to NCI-Working Group guidelines (see
Appendix C).

4. Eastern Cooperative Oncology Group Performance Status (ECOG PS) of ≤2 (see Appendix
A).

5. Laboratory values as follows ≤7 days of initiation of treatment:

- Creatinine <3.0 mg/dL

- Aspartate amino transferase (AST) or alanine amino transferase (ALT) and
alkaline phosphatase (ALP) must be <3 x upper limit of normal (ULN)

- Total bilirubin <1.5 x the institutional ULN

6. Patients must be hepatitis B sAg negative. Note: Patients who are HepB sAg negative
but are HepB cAb positive (regardless of HepB sAb status) will NOT be allowed.

7. Women of childbearing potential must have a negative serum pregnancy test performed
≤7 days prior to start of treatment. Women of childbearing potential or men with
partners of childbearing potential must use effective birth control measures during
treatment. If a woman becomes pregnant or suspects she is pregnant while
participating in this study, she must agree to inform her treating physician
immediately.

8. Patients ≤ 65 years of age, or patients 18-64 years of age who have declined
fludarabine-based regimens, are eligible.

9. Patient must be accessible for treatment and follow-up.

10. Patients must be able to understand the nature of this study, give written informed
consent prior to study entry, and comply with study requirements.

Exclusion Criteria:

1. Previous therapy for CLL/SLL. (Patients who have received steroids or IVIG for
autoimmune complications of CLL are eligible).

2. Current active hepatic or biliary disease (with the exception of patients with
Gilbert's syndrome, asymptomatic gallstones, liver metastases, or stable chronic
liver disease, per assessment by the treating physician).

3. Active bacterial or viral infection, or infection requiring intravenous antibiotic
treatment at the time of accrual.

4. Central nervous system lymphoma/CLL.

5. Transformation of CLL to aggressive non-Hodgkin lymphoma (NHL) (i.e., Richters
transformation).

6. History of other malignancy within 2 years of study entry which could affect
compliance with the protocol or interpretation of results. Patients with a history
of curatively treated basal or squamous cell carcinoma of the skin or in situ
carcinoma of the cervix, low grade, early-stage, localized prostate cancer treated
surgically with curative intent, ductal carcinoma in situ (DCIS) of the breast
treated with curative intent, are generally eligible. These cases should be
discussed with the study chair or study co-chair prior to enrollment.

7. Patients who are HepB sAg positive and/or HepB cAb positive.

8. Concurrent severe, intercurrent illness including, but not limited to, ongoing or
active infection, or psychiatric illness/social situations that would limit
compliance with study requirements.

9. Any condition that would prevent patient comprehension of the nature of, and risk
associated with, the study.

10. A serious underlying medical condition that would impair the ability of the patient
to receive protocol treatment.

11. A major surgical procedure, open biopsy, or significant traumatic injury ≤28 days of
beginning treatment, or anticipation of the need for major surgery during the course
of the study.

12. Treatment with any known non-marketed drug substance or experimental therapy within 5
terminal half lives or 4 weeks prior to visit 1, whichever is longer. Patients may
not receive any other investigational or anti-cancer treatments while participating
in this study.