Inclusion Criteria:

• ≥ 18 years old

• CLL as defined by the NCI 96 criteria (exception; patients may have bright surface immunoglobulin staining if negative for t[11;14] translocation or cyclin D1) or SLL as defined by WHO classification criteria and is refractory or relapsed as defined by one of the following:

  • Refractory disease: progressive disease while on therapy
  • Relapsed disease: progressive disease after at least one treatment course of therapy with disease response or stabilization
• ECOG performance status score of 0, 1, or 2
• Willing and able to provide written informed consent

Exclusion Criteria:

• Laboratory values of:

  • Platelet count < 30,000/µL
  • AST or ALT > 2 x ULN (upper limit of normal)
  • Total bilirubin > 2 x ULN
  • Creatinine > 2 mg/dL
• Chemotherapy, radiation therapy, immunotherapy, systemic corticosteroids (> 10 mg oral prednisone or equivalent), or systemic biologic anticancer therapy within 21 days before beginning study treatment
• Major surgery or hospitalization for a serious illness within the last 3 months
• Greater than three prior regimens (where a regimen is defined as a treatment for CLL/SLL given initially or after disease progression)
• Prior malignancy requiring current or prior treatment within the past 5 years, except for cervical neoplasia in situ and non-melanomatous skin cancer
• Uncontrolled hypertension