Haploidentical hematopoietic stem cell transplantation in aplastic anemia: a systematic review and meta-analysis of clinical outcome on behalf of the severe aplastic anemia working party of the European group for blood and marrow transplantation (SAAWP of EBMT)

• Published in: Bone marrow transplantation (Basingstoke) 2020-10, Vol.55 (10), p.1906-1917
• Main Authors: ElGohary, Ghada, El Fakih, Riad, de Latour, Regis, Risitano, Antonio, Marsh, Judith, Schrezenmeier, Hubert, Gluckman, Eliane, Höchsmann, Britta, Pierri, Filomena, Halkes, Constantijn, Alzahrani, Hazzaa, De la Fuente, Josu, Cesaro, Simone, Alahmari, Ali, Ahmed, Syed Osman, Passweg, Jakob, Dufour, Carlo, Bacigalupo, Andrea, Aljurf, Mahmoud
• Format: Article
• Language: English
• Subjects: 13/100; 42/100; 45/100; 631/532/1542; 692/699/1541; 96/100; Anemia; Antithymocyte globulin; Aplastic anemia; Blood; Bone marrow; Cell Biology; Clinical trials; Complications; Conditioning; Cyclophosphamide; Cytomegalovirus; Cytomegalovirus infections; Eltrombopag; Graft-versus-host reaction; Hematological diseases; Hematology; Hematopoietic stem cells; Internal Medicine; Medical research; Medicine; Medicine & Public Health; Medicine, Experimental; Meta-analysis; Methotrexate; Mortality; Patient outcomes; Prophylaxis; Public Health; Review Article; Stem cell transplantation; Stem Cells; Systematic review; Transplantation; Transplants & implants; Viremia
• ISSN: 0268-3369; 1476-5365
• DOI: 10.1038/s41409-020-0897-2

Aplastic anemia (AA) is a serious hematological disorder, which is solely cured by hematopoietic stem cell transplantation (HSCT). Haploidentical HSCT is an emerging modality with encouraging outcomes in several blood conditions. The present study aims to comprehensively assess the feasibility and safety of haploidentical HSCT in patients with severe and very severe AA. It is a systematic review and meta-analysis of studies related to haploidentical stem cell transplantation in idiopathic AA investigating rates of successful engraftment, acute graft-versus-host disease (aGvHD), chronic GvHD (cGvHD), transplant-related mortality (TRM), and posttransplantation viral infections (including cytomegalovirus [CMV]) in patients with AA. The effects of reduced-intensity conditioning (RIC) and nonmyeloablative conditioning (NMA), as well as various GvHD prophylaxis regimens on these outcomes were evaluated. In total 15 studies were identified, (577 patients, 58.9% males), successful engraftment was observed in 97.3% of patients (95% CI, 95.9–98.7) while grades II–IV aGvHD and cGvHD were reported in 26.6% and 25.0%, respectively. The pooled incidence of TRM was 6.7% per year (95% CI, 4.0–9.4). RIC regimens were associated with higher proportions of successful engraftment (97.7% vs 91.7%, P  = 0.03) and aGvHD (29.5% vs 18.7%, P  = 0.008) when compared with NMA regimens with no differences in cGvHD or mortality incidence. When compared with methotrexate-containing regimens and other regimens, posttransplant cyclophosphamide-containing regimens reduced the rates of aGvHD (28.6%, 27.8%, and 12.8%, respectively, P  = 0.02), CMV viremia (55.7%, 38.6%, and 10.4%, respectively, P