Inclusion Criteria:

• Histopathologically confirmed diagnosis of B-CLL with CD5, CD19, or CD23 positive clone.
• Rai Stage I through IV disease with evidence of progression as evidenced by the presence of one or more of the following:1. Disease-related B symptoms (fever of greater than 38 celsius (100.5 F) for greater than or equal to 2 weeks without evidence of infection, night sweats without evidence of infection, weight loss >10% within previous 6 months. 2. Evidence of progression marrow failure as manifested by: a. decrease in hemoglobin to <11g/dL or b. decrease in platelet count to <100x10 to the ninth/L within the previous 6 months or c. decrease in absolute neutrophil count (ANC) to <1.0x10 to the ninth/L within the previous 6 months. 3. Progressive splenomegaly to >2 cm below the left costal margin or other organomegaly with progressive increase over 2 consecutive clinic visits greater than or equal to 2 weeks apart. 4. Progressive lymphadenopathy with at least 5 sites of involvement with either two nodes at least 2cm in longest diameter or one node greater than or equal to 5cm in longest diameter with progressive increase over 2 consecutive visits greater than or equal to weeks apart. 5. Progressive lymphocytes with an increase of >50% over a 2-month period, or an anticipated doubling time of less than 6 months.
• Received no previous chemotherapy for B-CLL.
• Life expectancy of at least 12 weeks.
• WHO performance status of 0, 1, or 2.
• Serum creatinine less or equal to 2.0 times the institutional upper limit of normal (ULN) value.
• Adequate liver function as indicated by a total bilirubin, AST, and ALT less or equal to 2 times the institutional ULN value, unless directly attributable to the disease.
• Female patients with childbearing potential must have a negative serum pregnancy test within 2 weeks prior to randomization. Male and female patients must agree to use an effective contraceptive method while on study treatment, if appropriate, and for a minimum of 6 months after study therapy.
• Signed, written informed consent.
• 18 years of age or older.

Exclusion Criteria:

• ANC less than 500 million per liter or platelet count less than 10 billion per liter.
• Medical condition requiring chronic use of oral corticosteroids.
• Autoimmune thrombocytopenia.
• Previous bone marrow transplant.
• Use of investigational agents within previous 30 days.
• Positive for HIV.
• Past history of anaphylaxis following exposure to rat or mouse-derived complementary determining region (CDR) grafted humanized monoclonal antibodies.
• Active infection.
• Serious cardiac or pulmonary disease that could interfere with their ability to participate in the study.
• Recent documented (with in 2 years) of active tuberculosis (TB), current active TB, or currently receiving anti-tuberculosis medication.
• Active secondary malignancy.
• Central nervous system involvement with CLL.
• Positive quantitative CMV by PCR assay (using the laboratory normal ranges).
• A diagnosis of mantle cell lymphoma.
• Other severe, concurrent diseases or mental disorders.
• Pregnant or lactating women.