Lower Dose of Antithymocyte Globulin (ATG) does not increase Graft-vs-Host Disease (GVHD) in Patients Undergoing Reduced-Intensity Conditioning (RIC) Allogeneic Hematopoietic Stem Cell Transplant (allo HSCT)

摘要

The appropriate dose of antithymocyte globulin (ATG) been utilized in reduced-intensity conditioning (RIC) allogeneic hematopoietic stem cell transplantation (alloHSCT) is yet unknown. We retrospectively compared patients who received 7.5 mg/kg (R-ATG – 39 patients) and 6 mg/kg (r-ATG- 97 patients). The cumulative incidences of acute graft-versus-host-disease (aGVHD) grade II–IV at 180 days were 46% and 41% and aGVHD grade III–IV were 11% and 18% in r-ATG and R-ATG, respectively (P>0.30). The respective estimated cumulative incidences at 24 months of cGVHD were 42% and 44% (P>0.3). There was no significant difference in non-relapse mortality (p=0.22), cumulative incidence of relapse (p=0.53), progression-free survival (p=0.69) or overall survival (p=0.95). In conclusion, a decreased ATG dose of 6 mg/kg was associated with a similar proportion of GVHD as 7.5 mg/kg ATG. Given the increasing number of RIC HSCT performed worldwide, the correct dose and preparation of ATG should be defined by prospective randomized trials.