Severe aplastic anemia(SAA) is a life-threatening disease that can be cured with allogeneic cell transplantation(HCT). Haploidentical donor transplantation with posttransplant cyclophosphamide(Haplo-PTCy) is an option for patients lacking HLA matched donor. We analyzed 87 patients who received Haplo-PTCy between 2010 and 2019. Median age was 14(range, 1-69), most were heavily transfused and all received previous immunosuppression(25% without ATG). Most(63%) received standard Flu-Cy29-TBI200 conditioning, and the remaining ones received an augmented conditioning: Flu-Cy29-TBI300-400(16%), Flu-Cy50-TBI200(10%) or Flu-Cy50-TBI400(10%). All received PTCy-based GVHD-prophylaxis. Most grafts(93%) were bone marrow(BM). Median follow-up was 2 years and 2 months. Median days of neutrophil recovery was 17 days. Primary graft failure occurred in 15%, and secondary or poor graft function in 5%. Incidences of grade II-IV acute and chronic GVHD were 14% and 9%. Two-year OS and EFS were 79% and 70%. EFS was higher for patients given augmented FluCyTBI(HR=0.28, p=0.02), and in those patients given higher BM CD34 cell dose(>3.2 × 10E6/kg) (HR=0.29, p=0.004). The presence of donor-specific antibodies(DSA) previous to transplant was associate with lower EFS(HR=3.92, p=0.01). Graft failure(HR=7.20, p<0.0001) was associated with a higher risk of death. CMV reactivation was frequent(62%). Haploidentical HCT for SAA is a feasible procedure; outcomes are improved with augmented conditioning regimen and higher BM CD34 cell grafts.
Copyright © 2020. Published by Elsevier Inc.