Allogeneic Stem Cell Transplantation in Chronic Myeloid Leukemia Failing TKIs Therapy

Inclusion Criteria: 1. Chronic Myeloid Leukaemia -CML- in chronic phase (CP) 2. Failure to achieve at least a Major Cytogenetic Response (MCyR) after a minimum of 18 months of TKIs treatment 3. Inability to tolerate 3 months of uninterrupted full dose TKIs therapy due to hematological toxicity 4. A minimum of three treatment interruptions due to hematological toxicity Availability of a HLA-identical related donor (Matched Related Donor, MRD) 5. Availability of unrelated donor (Matched Unrelated Donor, MUD) satisfying the criteria of a 10/10 antigen match at (Human Leukocyte Antigen) HLA-A, -B, -C and - DRB1, -DQB1 at high resolution typing, or 9/10 with a permissive - DP disparity according to Fleischhauer model (Crocchiolo et al, Blood 2009) 6. Target graft size (bone marrow): 7. bone marrow: \> 3 x 106 CD34+ cells/kg BW recipient or \> 3 x 108 nucleated cells/kg BW 8. Karnofsky Index \> 80 % 9. Age ≥18 and ≤70 years 10. Adequate contraception in female patients of child-bearing potential 11. Written informed consent Exclusion Criteria: 1. Secondary malignancies 2. A hematopoietic cell transplantation-specific comorbidity index (Sorror et al Appendix C) \> 4 3. Known and manifested malignant involvement of the Central Nervous System (CNS) 4. Active infectious disease 5. Active human immunodeficiency virus (HIV), Hepatitis B virus (HBV) or Hepatitis B virus (HCV) infection 6. Impaired liver function (Bilirubin \> upper normal limit; Transaminases \> 3.0 x upper normal limit) 7. Impaired renal function (Creatinine-clearance \< 60 ml/min; Serum Creatinine \> 1.5 x upper normal limit). 8. Pleural effusion or ascites \> 1.0 L 9. Pregnancy or lactation 10. Known hypersensitivity to Busilvex and/or fludarabine 11 Non-co-operative behaviour or non-compliance 12 Psychiatric diseases or conditions that might impair the ability to give informed consent