Sequential allogeneic hematopoietic stem cell transplantation for active refractory/relapsed myeloid malignancies: results of a reduced-intensity conditioning preceded by clofarabine and cytosine arabinoside, a retrospective study on behalf of the SFGM-TC

Ann Hematol. 2020 Aug;99(8):1855-1862. doi: 10.1007/s00277-020-04074-7. Epub 2020 Jun 20.

Abstract

Allogeneic stem cell transplantation (allo-SCT) represents the most beneficial treatment for patients with active relapsed/refractory (R/R) hematologic malignancies. Recently, sequential regimens combining debulking chemotherapy followed by reduced-intensity conditioning (RIC) have shown encouraging results for these patients. In this retrospective study, we report the extended results of a sequential regimen of clofarabine, cytosine arabinoside, and RIC in 131 adults with active R/R myeloid disease at transplant. Conditioning consisted of clofarabine (30 mg/m2/day) and cytosine arabinoside (1 g/m2/day) for 5 days, followed, after a rest of 3 days, by an RIC combining cyclophosphamide (60 mg/kg) for 1 day, iv busulfan (3.2 mg/kg/day) for 2 days, and anti-thymocyte globulin (2.5 mg/kg/day) for 2 days. Between 2007 and 2016, 131 patients (males n = 75, median age: 52.6 years) were identified from the SFGM-TC registry. There were 111 acute myeloid leukemia (AML) patients and 20 cases with myelodysplastic or myeloproliferative syndrome. Status at transplant was known for all but 4 patients and was primary refractory (n = 81) and 1st or 2nd relapse (n = 46). All patients received allo-SCT from a matched donor (sibling n = 64, unrelated n = 67). Engraftment was observed in 105/122 (86%) evaluable cases and 63% of the patients achieved complete remission (CR) after transplant. The 1-year overall survival, disease-free survival, relapse incidence, non-relapse mortality, and graft-versus-host disease-free/relapse-free survival were 39.2%, 28.1%, 41.0%, 30.8%, and 22.2%, respectively. This study confirms that this sequential clofarabine-based regimen provides a high CR rate in this critical population, although relapse remains a matter of concern.

Keywords: Acute myeloid leukemia; Allogeneic stem cell transplantation; Clofarabine; Reduced intensity conditioning regimen; Sequential regimen.

Publication types

  • Clinical Trial
  • Multicenter Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Allografts
  • Antineoplastic Combined Chemotherapy Protocols / administration & dosage*
  • Clofarabine / administration & dosage
  • Cytarabine / administration & dosage
  • Disease-Free Survival
  • Female
  • Hematopoietic Stem Cell Transplantation*
  • Humans
  • Leukemia, Myeloid, Acute* / mortality
  • Leukemia, Myeloid, Acute* / therapy
  • Male
  • Middle Aged
  • Myelodysplastic Syndromes* / mortality
  • Myelodysplastic Syndromes* / therapy
  • Retrospective Studies
  • Survival Rate
  • Transplantation Conditioning*

Substances

  • Cytarabine
  • Clofarabine