['chronic lymphocytic leukemia']
['ibrutinib', 'placebo']

        Inclusion Criteria:

          -  Previously untreated CLL

          -  Stage Binet A without need for treatment

          -  Age ≥ 18 years

          -  Life expectancy ≥ 6 months

          -  ECOG 0 - 2

          -  Signed written informed consent

          -  Patient in the experimental arm is willing to use a highly effective contraceptive
             method

          -  Male subjects in the experimental treatment arm (placebo / ibrutinib) must:

          -  Agree to not donate semen during study drug therapy and for a period after end of
             study drug therapy.

          -  For males these restrictions apply for 3 months after the last dose of study
             medication.

          -  Agree not to share study medication with another person.

          -  Be counseled about pregnancy precautions and risks of fetal exposure.

          -  Willingness to inform the general practitioner

        Exclusion Criteria:

          -  Any prior CLL specific therapy

          -  Prior treatment with Ibrutinib or BTK inhibitors

          -  Chronic use of steroids in excess of prednisone 20mg/day or its equivalent

          -  Active infections requiring systemic antibiotics

          -  An life-threatening illness, medical condition, or organ system dysfunction which, in
             the investigator's opinion could compromise the subject's safety, interfere with the
             absorption or metabolism of Ibrutinib capsules, or put the study outcomes at undue
             risk

          -  Pregnant or lactating females

          -  Central nervous system (CNS) involvement as documented by spinal fluid cytology or
             imaging. Subjects who have signs or symptoms suggestive of leukemic meningitis or a
             history of leukemic meningitis must have a lumbar puncture procedure performed within
             two weeks prior to randomization

          -  Known second malignancy that limits survival to less than two years

          -  Known Human Immunodeficiency Virus (HIV), active Hepatitis B Virus (HBV) and/or active
             Hepatitis C Virus (HCV) infection.

          -  Any of the following laboratory abnormalities:

               1. Serum aspartate aminotransferase (AST)/serum glutamic-oxaloacetic transaminase
                  (SGOT) or alanine transaminase (ALT)/serum glutamate pyruvate transaminase (SGPT)
                  > 2.5 x upper limit of normal (ULN)

               2. Serum total bilirubin > 1.5 ULN (with the exception of Gilbert's Syndrome)

               3. Creatinine clearance < 30ml/min

          -  Requires anticoagulant with warfarin or phenoprocoumon

          -  Requires anticoagulant with oral direct Xa Inhibitors (rivaroxaban, apixaban,
             edoxaban)

          -  History of stroke or intracranial hemorrhage within 6 months prior to randomization

          -  Requires treatment with strong CYP3A4/5 Inhibitors

          -  Participation in any clinical study for CLL or having taken any investigational
             therapy which would interfere with the study drug for a disease other than CLL within
             28 days prior to initiating treatment.

          -  Prisoners or subjects who are institutionalized by regulatory or court order or
             persons who are in dependence to the sponsor or an investigator

          -  Patients with uncontrolled autoimmune hemolytic anemia or autoimmune thrombocytopenia

          -  For males these restrictions apply for 3 months after the last dose of study
             medication.

          -  Agree not to share study medication with another person.

          -  Be counseled about pregnancy precautions and risks of fetal exposure.

          -  Willingness to inform the general practitioner

          -  Requires anticoagulant with warfarin or phenoprocoumon

          -  Requires anticoagulant with oral direct Xa inhibitors (rivaroxaban, apixaban,
             edoxaban)
      