Campath-1H Plus Rituximab for CD52- and CD20- Positive Refractory or Relapsed Chronic Lymphoid Disorders

Inclusion Criteria: 1. Age \>/=15 years. 2. Written informed consent. 3. Patients with chronic lymphoid malignancies that are either refractory to frontline therapy or have relapsed and that have a predicted probability of response of less than 20% with conventional therapy or allogeneic/autologous stem cell transplantation. 4. The following histologies are included: B-cell chronic lymphocytic leukemia (B-CLL or B-cell CLL), B-cell prolymphocytic leukemia (PLL), chronic lymphoid leukemia (CLL/PLL), hairy cell leukemia and hairy cell variant, mantle cell leukemia/lymphoma, marginal zone lymphoma/leukemia, splenic lymphoma with villous lymphocytes, CLL with evidence of transformation (e.g., Richter's transformation), large granular lymphocytic leukemia (LGL and NK-cell type). 5. Patients with above mentioned histologies whose malignant cell population have expressed both CD52 and CD20 in \>/= 20% of cells as assessed by flow cytometry or immunohistochemistry. Expression of CD20 or CD52 \< 20% is permitted if patients received rituximab or alemtuzumab, respectively, within 3 months prior to study start. Exclusion Criteria: 1. Patients who have previously received Rituximab and CAMPATH-1H in combination are excluded. 2. ECOG performance status of \</= 2. 3. Serum creatinine \</= 2mg/dL and total bilirubin of £ 2 mg/dL unless due to direct infiltration of the liver or kidney with malignant cells. 4. Patients with a past history of anaphylaxis following exposure to rat or mouse derived CDR-grafted humanized monoclonal antibodies are excluded \<CDR = complementarity determining regions\>. 5. Negative pregnancy test (serum or urine) if female and of childbearing potential only (non-childbearing is defined as greater than one year post-menopausal or surgically sterilized). 6. No prior chemotherapy, immunotherapy, or hormonal therapy within 2 weeks prior to study start. Hormonal replacement therapy is permitted. No prior therapy with monoclonal antibodies for at least 4 weeks prior to study start. 7. Patients at high risk of hepatitis B virus (HBV) infection and active HBV infection are excluded.