TCR-alpha/beta and CD19 depletion and treosulfan-based conditioning regimen in unrelated and haploidentical transplantation in children with acute myeloid leukemia

Bone Marrow Transplant. 2016 May;51(5):668-74. doi: 10.1038/bmt.2015.343. Epub 2016 Jan 25.

Abstract

We evaluated the depletion of TCR-alpha/beta cells from the graft of children with high-risk AML, who received transplantation from unrelated (n=20) and haploidentical donors (n=13). The preparative regimen included treosulfan, melphalan, fludarabine and anti-thymocyte globulin. Grafts were PBSC engineered by TCR-alpha/beta and CD19 depletion. The graft contained a median of 9 × 10(6)/kg of CD34+ and 20 × 10(3)/kg of αβ-T cells. Post-transplant immune suppression included tacrolimus till day +30 and Mtx in 21 patients, tacrolimus in 5, Mtx in 2 and no prophylaxis in 5 patients. Sixteen patients received native or TCR-alpha/beta-depleted donor lymphocytes at a median of 47 (40-204) days. Median follow-up is 1.76 years. Primary engraftment was achieved in 33 patients (100%). Cumulative incidence of acute GvHD (aGvHD) grade 2-3 was 39 (26-60)%, half of them had skin-only aGvHD. Cumulative incidence of chronic GvHD was 30(18-50)%. Transplant-related mortality is 10(4-26)%. Event-free survival (EFS) is 60(43-76)% and overall survival (OS) is 67(50-84)% at 2 years. In a subgroup of patients, who received transplantation in CR, EFS is 66(48-84)% and OS-72(53-90)% at 2 years. Our data suggest that TCR-alpha/beta and CD19 depletion is a robust method of graft manipulation, which can be used to engineer grafts for children with AML.

MeSH terms

  • Adolescent
  • Antigens, CD19 / analysis*
  • Antigens, CD19 / isolation & purification
  • Busulfan / analogs & derivatives*
  • Busulfan / therapeutic use
  • Child
  • Child, Preschool
  • Disease-Free Survival
  • Female
  • Graft Survival
  • Graft vs Host Disease
  • Humans
  • Infant
  • Leukemia, Myeloid, Acute / complications
  • Leukemia, Myeloid, Acute / mortality
  • Leukemia, Myeloid, Acute / therapy*
  • Male
  • Receptors, Antigen, T-Cell, alpha-beta / analysis*
  • Receptors, Antigen, T-Cell, alpha-beta / isolation & purification
  • Transplantation Conditioning / methods*
  • Transplantation, Haploidentical / methods*
  • Transplantation, Haploidentical / mortality
  • Unrelated Donors
  • Young Adult

Substances

  • Antigens, CD19
  • Receptors, Antigen, T-Cell, alpha-beta
  • treosulfan
  • Busulfan