Influence of Donor Type (sibling vs matched-unrelated donor vs haplo-identical donor vs cord blood) on Outcomes after Clofarabine-Based Reduced-Intensity Conditioning Allograft for Myeloid Malignancies

• Published in: Blood 2018-11, Vol.132 (Supplement 1), p.3451-3451
• Main Authors: Bouard, Louise, Guillaume, Thierry, Peterlin, Pierre, Garnier, Alice, Le Bourgeois, Amandine, Duquesne, Alix, Mahe, Beatrice, Dubruille, Viviane, Blin, Nicolas, Touzeau, Cyrille, Gastinne, Thomas, Lok, Anne, Bonnet, Antoine, LE Gouill, Steven, Moreau, Philippe, Bene, Marie C, Chevallier, Patrice
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2018-99-112369

Background: Recently, we have reported the good results of a clofarabine-based reduced-intensity conditioning (RIC) regimen for peripheral blood stem cell (PBSC) allografts, using either matched (Le Bourgeois, ASH 2017) or haploidentical (haplo) donors (Chevallier, ASH 2017). However, the influence of donor type in this setting is unknown. Patients and Methods: We conducted a retrospective study including all adults (≥18 yo) allografted in our department with a clofarabine-based RIC regimen for a myeloid malignancy. All types of donors were accepted, and patients received allogeneic peripheral blood stem cells (PBSC) or cord blood (CB) transplants. The aim of this study was to assess whether or not the donor type (sibling, matched unrelated (MUD), haplo or CB) impacted outcomes. Results: Between October 2009 and February 2018, 122 patients met the inclusion criteria. Donors were sibling in 36 cases, “MUD” in 55 (including one 9/10 mismatched donor), haplo in 27 and CB in 4. The sibling+MUD patients received a CloB2A1/A2 RIC regimen consisting of clofarabine 30 mg/m²/day 4 to 5 days (Clo), busulfan 3.2 mg/kg/day 2 days (B2) and 2.5mg/kg/day of rabbit anti-thymocyte globulin 1 or 2 days (A1 or A2). Haplo and CB recipients were conditioned by a Baltimore-like RIC regimen and a Minneapolis-like regimen, respectively, where fludarabine were replaced by clofarabine. All patients received cyclosporine (CsA) + mycophenolate mofetyl as GVHD prophylaxis, except sibling recipients who were given CsA alone. Haplo recipients received also 2 days of post-transplant cyclophosphamide. All non-CB patients received PBSC as source of graft. The median age of the whole cohort was 61,5 years old (range: 18-73) and the median follow-up 31 months (range: 4,5-106). All patients engrafted except 1 CB patient and 1 haplo recipient who died of infection before engraftment. All CB cases died at 1, 8, 9 and 11,5 months post-transplant, respectively (infection n=1, relapse n=2, chronic GVHD n=1). As a consequence, we thereafter compared outcomes only between the three other donor groups. There were no significant differences between sibling, MUD or haplo recipient groups in terms of gender, median age, type of disease, ELN 2010 classification for AML, status at transplant (complete remission vs active), disease risk index, donor/recipient CMV status or median graft quantity of CD34+ stem cells. The only differences were the partition of ABO compatibility, less frequent in the MUD group