Inclusion Criteria

Inclusion criteria:

1. Diagnosis of relapsed or refractory chronic lymphocytic leukaemia.

2. At least two prior treatment regimens for chronic lymphocytic leukaemia.

3. At least one criterion for active disease as defined by the National Cancer Institute
Working Group.

4. Absolute lymphocyte count between 5 x 10 9/l and 150 x 10 9/l .

5. Eastern Cooperative Oncology Group (ECOG) Performance Status 0, 1 or 2.

6. Age 18 years or older.

7. Written informed consent which is consistent with International Conference on
Harmonisation - Good Clinical Practice (ICH-GCP) guidelines and local legislation.

Exclusion criteria:

1. Treatment with anti CD 20 therapy within 28 days or alemtuzumab within 8 weeks prior
to enrolment.

2. Prior allogeneic stem cell transplantation.

3. Active autoimmune haemolytic anemia.

4. Active autoimmune thrombocytopenia.

5. Known transformation to an aggressive B-cell malignancy.

6. Concurrent treatment with relevant doses of systemic glucocorticosteroids.

7. Prior history of malignancy other than chronic lymphocytic leukaemia (exceptions to
this rule are defined in the clinical trial protocol).

8. Aspartate aminotransferase or alanine aminotransferase > 2.5 x upper limit of normal.

9. Total bilirubin > 1.5 x upper limit of normal.

10. Absolute Neutrophil Count < 1.000/µl.

11. Platelets < 25.000/µL.

12. Estimated Glomerular Filtration Rate <60 mL/min.

13. Proteinuria Common Terminology Criteria for Adverse Events (CTCAE) grade 2 or higher.

14. Significant concurrent disease.

15. Any infectious disease requiring treatment at the time of enrolment or within the
previous 2 weeks.

16. Hepatitis B or C.

17. Human Immunodeficiency Virus (HIV) infection.

18. Cytomegalovirus (CMV) viremia.

19. Women of childbearing potential not using a highly effective method of birth control
during the trial until one year after the last dose.

20. Pregnancy or breast feeding.

21. Known or suspected active alcohol or drug abuse.

22. Treatment with another investigational drug within the past four weeks before start
of therapy or concomitantly with this trial.

23. Prior treatment with BI 836826.

24. Patients unable to comply with the protocol