Inclusion Criteria:

- B-cell Chronic Lymphocytic Leukemia (B-CLL) according to the 1996 National Cancer
Institute-sponsored Working Group (NCI-WG) Criteria

- One or more, but <= 3 previous treatment regimens for Chronic Lymphocytic Leukemia
(CLL)

- Patient requires treatment for CLL (Rai stage III and IV disease or stage 0 to II
disease with evidence of progression)

- Adequate bone marrow, liver and renal function

- More than 4 weeks since prior chemotherapy or chemoimmunotherapy, including
investigational agents, for the treatment of CLL. Patient must have recovered from
the acute side effects incurred as a result of previous therapy

- World Health Organization (WHO) Performance Status (PS) 0,1

- Life expectancy of at least 24 weeks

- Women of childbearing potential must have a negative serum or urine pregnancy test
performed within 7 days prior to the start of treatment. Both men and women enrolled
in this trial must use adequate barrier birth control measures during the course of
the trial and 2 weeks after the completion of trial

- Written informed consent

Exclusion Criteria:

- Known human immunodeficiency virus (HIV) seropositivity

- Active hepatitis or a history of prior viral hepatitis B or hepatitis C, or positive
hepatitis B serologies. Patients with a positive hepatitis B surface antibody
(HBsAb) test with a documented history of prior hepatitis B immunization are eligible
as long as other criteria are met (i.e., negative tests for : hepatitis B surface
antigen [HBsAg], hepatitis B core antibody [HBcAb] and hepatitis C virus antibody
[HCVAb])

- Active uncontrolled infection

- Recent documented history (within 2 years) of active tuberculosis (TB), current
active TB infection, currently receiving anti-tuberculous medication (e.g.,
isoniazid, rifampin, streptomycin, pyrazinamide, or others)

- Positive cytomegalovirus (CMV) by Polymerase Chain Reaction (PCR) assay

- Transformation to aggressive lymphoma (e.g., Richter's syndrome)

- Past history of anaphylaxis following exposure to humanized monoclonal antibodies

- Previous treatment with alemtuzumab

- Previous hematopoietic stem cell transplant

- Pregnant or breast-feeding patients

- Central nervous system (CNS) involvement with CLL

- Other severe, concurrent diseases (e.g., cardiac or pulmonary disease), mental
disorders, or major organ malfunction (e.g., liver, kidney) that could interfere with
the patient's ability to participate in the study

- Medical condition requiring chronic use of oral corticosteroids at a dose higher than
physiologic replacement.

- Active malignancy, other than CLL, which needs therapy with anti-cancer drug(s)

- Autoimmune anemia and/or thrombocytopenia

- Small lymphocytic lymphoma