Outcomes of Antithymocyte Globulin-Post-Transplantation Cyclophosphamide-Cyclosporine-Based versus Antithymocyte Globulin-Based Prophylaxis for 10/10 HLA-Matched Unrelated Donor Allogeneic Hematopoietic Cell Transplantation.

In 2015, dual T cell depletion with antithymocyte globulin (ATG) and post-transplantation cyclophosphamide (PTCy) combined with cyclosporine A (CsA) replaced our prior institutional graft-versus-host disease (GVHD) prophylaxis regimen of 4.5 mg/kg ATG, CsA, and mycophenolate mofetil (MMF) (ATG-based) in 10/10 HLA-matched unrelated donor (MUD) peripheral blood allogeneic hematopoietic stem cell transplantation (allo-HCT). The initial ATG dose of 4.5 mg/kg [ATG(4.5)/PTCy] was reduced to 2 mg/kg [ATG(2)/PTCy] in 2018. This study compares the results obtained from 444 adults undergoing MUD allo-HCT at our institution who received ATG(4.5)/PTCy (n = 127) or ATG(2)/PTCy (n = 223) with those who received ATG-based prophylaxis without PTCy (n = 84). The rates of grade II-IV and grade III-IV acute GVHD (aGVHD) at day +100 and moderate/severe chronic GVHD (cGVHD) at 1 year were 35.7%, 21.6%, and 14.7%, respectively, in patients receiving ATG-based prophylaxis without PTCy; 16.5%, 4.9%, and 4.3% in patients receiving ATG(4.5)/PTCy; and 23.3% (P = .004), 8.0% (P < .001), and 14.1% (P =.006) in patients receiving ATG(2)/PTCy. One-year overall survival (OS), nonrelapse mortality (NRM), and GVHD-free relapse-free survival (GRFS) were 69.8%, 25.3%, and 52.0%, respectively, for patients receiving ATG-based prophylaxis without PTCy; 82.7%, 17.3%, and 59.8% for patients receiving ATG(4.5)/PTCy; and 78.3% (P = .446), 14.7% (P = 101), and 56.2% (P = .448) for patients receiving ATG(2)/PTCy. On univariate analyses, the use of ATG(2)/PTCy was associated with a lower risk of NRM (hazard ratio, .54; P = .023) compared with the use of ATG-based prophylaxis without PTCy. ATG(2)/PTCy prophylaxis effectively prevents GVHD and is associated with comparable relapse risk, OS, and GRFS as seen with ATG(4.5)/PTCy and ATG-based prophylaxis without PTCy.

Allogeneic stem cell transplant in myelodysplastic syndrome-factors impacting survival.

OBJECTIVES: The primary aim of this study was to evaluate survival outcomes following allo-HCT in myelodysplastic syndrome (MDS), and the secondary aim was to study variables impacting survival. METHODS: This analysis describes patient characteristics, treatment, and outcomes in 125 consecutive adult patients with MDS transplanted from 2005 to 2018. RESULTS: The median age was 61 years, and median follow-up in patients alive at last follow-up was 29 months. The 2-year OS and RFS were 39% (95%CI 30%-48%) and 35.3% (95% CI: 27%-44%), respectively. Transfusion dependence, high-risk cytogenetics, and high serum ferritin were independent risk factors for death. The cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) at 2 years were 23% and 41.6%, respectively. High serum ferritin was significantly associated with NRM. There was no association between the percentage of bone marrow blasts (either at diagnosis or at pretransplant evaluation), on relapse or survival. Induction chemotherapy did not offer any survival advantage in MDS RAEB-2 patients compared to cytoreduction with azacytidine alone. CONCLUSION: Our results highlight the importance of karyotype on survival after allo-HCT and identify serum ferritin and transfusion dependence as important surrogate markers of outcome. In addition, our results demonstrate the efficacy of azacytidine for pretransplant cytoreduction.

Low rates of acute and chronic GVHD with ATG and PTCy in matched and mismatched unrelated donor peripheral blood stem cell transplants.

INTRODUCTION: We evaluated the combination of ATG and PTCy for GVHD prophylaxis in matched and mismatched unrelated PBSCTs for high-risk hematological malignancies. METHODS: We treated 102 patients with reduced intensity conditioning (RIC) with fludarabine, busulfan, and TBI 200 cGy. GVHD prophylaxis included rabbit ATG (thymoglobulin at total dose of 4.5 mg/kg divided over days -3 to -1), PTCy (50 mg/kg/day on day +3 and on day +4), and cyclosporine. Clinical and outcome data were collected retrospectively. RESULTS: Among 102 patients, 76 patients received 10/10 MUD transplants and 26 patients received 9/10 mismatched transplants. The median age was 59 years. At a median follow-up of 15 months (range 0.6 to -33 months), the 1-year OS in MUD and MMUD cohort was 75% and 50%, respectively (P = 0.027). The corresponding one-year PFS was 67% and 35%, respectively (P = 0.0024). The incidence of grade 3-4 acute GVHD was 11.8% in MUD and 3.8% in MMUD group, and that of NIH stage moderate/severe chronic GVHD in the 2 groups was 10.5% and 7.6%, respectively. Cytomegalovirus (CMV) reactivation was seen in 49% patients. The cumulative incidence of relapse was 21.1% in the MUD group and 42.3% in the MMUD group. CONCLUSION: Our experience shows that PTCy and ATG can be combined for GVHD prophylaxis in matched unrelated donor PBSCTs with low rates of Gr3-4 acute GVHD and chronic GVHD, and acceptable relapse rates.