Inclusion Criteria:

- Confirmed diagnosis of CLL according to the NCI Working Group criteria.

- Male and female patients of age >18 and ≤75 years

- Patients relapsed/refractory within 1 month after conventional chemotherapy (>1
polychemotherapy regimen) or relapsed within 3 months after autologous bone marrow
transplantation

- ECOG performance score of ≤2

- Limphocytes ≥10.0x10^9/L and platelets >75.0x10^9/L after recovery from a previous
therapy

- Percentage of CD19+/CD5+ leukemic cells >50%

- Adequate cardiac, pulmonary and renal function, as defined by LVEF >45%, FEV >50%
and creatinine ≤1.5 ULN or creatinine clearance ≥50ml/min

- Serum bilirubine <1.5xULN, AST and ALT <2.5xULN

- Serum potassium, phosphorus, total calcium, magnesium >LLN

- Normal values for FT4 and TSH (patients may be on thyroid hormone replacement)

- Negative test for beta-HCG for women in fertile age

- Documentation of written informed consent to participate in the trial

- Willingness and ability to comply with scheduled visits, treatment plan, laboratory
tests and other study procedures.

Exclusion Criteria:

- Patients with Autoimmune haemolytic anaemia, Autoimmune Thrombocytopenic Purpura and
Fischer Evans Syndrome.

- Patients with other autoimmune diseases.

- Patients with a marked baseline prolongation of QTc interval (e.g. repeated
demonstration of a QTc interval >450 ms).

- Patients with history of additional risk factors for torsade de pointes (e.g. hearth
failure, family history of Long QT Syndrome)

- The use of concomitant medications with potential risk of torsade de pointes and/or
that can prolong QTc interval

- Prior treatment with an HDAC inhibitor.

- Treatment with Rituximab or Alemtuzumab within 90 days prior to study therapy.

- Patients HIV positive, patients with active EBV, HBV, HCV infection or liver
cirrhosis

- Patients with active uncontrolled viral or bacterial or mycotic infection.

- Major surgeries within 4 weeks from study start or not fully recovered from any
previous surgical procedure.

- Presence of any medical or psychiatric condition which may limit full compliance with
the study or increase the risk associated with study participation or study drug
administration.

- Patients in treatment with corticosteroids within 1 month before study start

- Significant cardiovascular disease (i.e., uncontrolled arrhythmias, unstable angina),
or a major thromboembolic event (myocardial infarction, stroke, transient ischemic
attack, pulmonary embolism, or non-catheter-related deep-vein thrombosis) in the last
6 months.

- Uncontrolled hypertension.

- Malabsorption syndromes.

- Breast feeding women