Inclusion Criteria:

          1. Male or female patients ≥18 years old

          2. Diagnosis of Ph-positive (by cytogenetics) or BCR-ABL-positive (by PCR) CP-CML

          3. Patients should have demonstrated to have

               -  a failure of a prior 1st line TKI treatment with either imatinib, dasatinib or
                  nilotinib. Failure is defined as per European LeukemiaNet (ELN) recommendations:

                    -  Less than Complete Hematologic Response (CHR) and/or Ph+ > 95% at or beyond
                       3 months

                    -  No cytogenetic response (Ph+>35%) and/or Abelson murine leukemia viral
                       oncogene homolog 1 (BCR-ABL1) >10% at or beyond 6 months

                    -  BCR-ABL (on international scale) >1% and/or PH+ >0%

                    -  Less than MMR at or beyond 18 months

                    -  Loss of response or development of mutations or other clonal chromosomal
                       abnormalities at any time during the first line TKI treatment

               -  or intolerance to prior TKI treatment defined as grade 3 or 4 toxicity, or
                  persistent grade 2 toxicity despite optimal management including dose adjustment,
                  or in a patient where dose reductions are considered to be not in the patient's
                  best interest to obtain an adequate response. Intolerant patients should not have
                  achieved or have lost major molecular response at the time of enrollment

          4. Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2

        Exclusion Criteria:

          1. Any 1st line anti-CML treatment other than TKI (apart from therapy with hydroxyurea)

          2. Any 2nd line therapy with a tyrosine kinase inhibitor (>1 European Medicines Agency
             (EMA) approved TKI for CML, or any investigational non EMA-approved TKI)

          3. Concurrent participation in any other clinical trial involving another investigational
             drug within 4 weeks prior to enrollment and throughout participation in PONS-Study

          4. New York Heart Association (NYHA) cardiac class 3-4 heart disease

          5. Cardiac Symptoms within the past 12 months prior recruitment