Salvage Haploidentical Transplantation for Graft Failure after First Haploidentical Allogeneic Stem Cell Transplantation: An Updated Experience

Abstract Second transplantation was almost the only salvage for graft failure. However, there is no recommended regimens for second transplantation, especially in the haplo-SCT setting. We recently reported very encouraging outcomes using a novel method (salvage haploidentical transplantation from a different donor after conditioning with fludarabine 30mg/m2 from − 6d to -2d and cyclophosphamide 1g/m2 from − 5d to -4d). Herein, we reported our updated experience in a total of 30 patients using this method. The median time of the second transplantation was 96.5 (33–215) days after the first transplantation. Among the 30 patients, 2 used the same donor since there was no other donor available. One patient died before engraftment at 19 days after second transplantation. For the 29 evaluable patients, neutrophil engraftments were achieved in all (100%) patients at a median of 11 (8–24) days, while platelet engraftments were achieved in 22 (75.8%) patients at a median of 17.5 (9-140) days. The 1-year OS and DFS was 60% and 53.3%, respectively. CIR and TRM was 6.7% and 33.3%, respectively. Compared with historical group (n = 34), the neutrophil engraftment (100% versus 58.5%, p < 0.001) and platelet engraftment (75.8% versus 32.3%, p < 0.001) were significantly better in the novel regimen group, and the OS was also significantly improved (60.0% versus 26.4%, p = 0.011). In conclusion, salvage haploidentical transplantation from a different donor using Flu/Cy regimen represents a promising option to rescue patients with graft failure after the first haploidentical stem cell transplantation.