Single-Agent Cyclosporine for Graft-versus-Host Disease Prophylaxis in Patients with Acquired Aplastic Anemia Receiving Fludarabine-Based Conditioning

Abstract

Cyclosporine (CsA) combined with short-course methotrexate is considered standard-of-care graft-versus-host disease (GVHD) prophylaxis for patients with severe aplastic anemia (AA) who undergo transplantation using cyclophosphamide (Cy) plus anti-thymocyte globulin (ATG) conditioning. However, there is no consensus on optimal post-transplant GVHD prophylaxis for patients undergoing matched related donor (MRD) transplantation using fludarabine (Flu)-based conditioning. We conducted a single-center retrospective analysis of patients with acquired AA (n = 106) undergoing MRD transplantation from July 2007 through January 2019. All patients received Flu-Cy-ATG conditioning and single-agent CsA as GVHD prophylaxis. Median age of the study cohort was 20 years (range, 3 to 52) and male to female ratio was 3.8:1. Median time from diagnosis to transplant was 11.5 months (range, 2.8 to 62). Graft source was bone marrow harvest in 71 (68%), combined bone marrow and peripheral blood stem cells in 34 (31%), and peripheral blood alone in 1 (1%) patient. Cumulative incidence of neutrophil engraftment at day 28 was 93.4% (95% confidence interval [CI], 87.3% to 97.1%) while that of platelet engraftment at day 100 was 90.5% (95% CI, 84% to 96%). Cumulative incidence of primary graft failure at day 28 was 6.6% (95% CI, 4% to 8%) while secondary graft failure occurred at a median of 190 days (range, 90 to 415) at a cumulative incidence of 3.7% (95% CI, 2% to 5%). Cumulative incidence of grade II to IV acute GVHD at day 100 was 3.8% (95% CI, 1.4% to 9.9%), while a 1-year probability of chronic GVHD was calculated as 7.5% (95% CI, 2.6% to 15%). Median follow-up post-transplant was 61 months (range, 6 to 144). Overall survival was 84.9%, disease-free survival was 80.2%, and GVHD-free relapse-free survival was 76.3%. This study indicates that single-agent cyclosporine is a feasible option for GVHD prophylaxis in MRD hematopoietic stem cell transplantation using Flu-Cy-ATG conditioning and is associated with very low rates of acute and chronic GVHD.

Keywords: Aplastic anemia; Cyclosporine; Fludarabine; Graft-versus-host disease.