Post-Transplant Cyclophosphamide–Based Graft-Versus-Host Disease Prophylaxis Attenuates Disparity in Outcomes Between Use of Matched or Mismatched Unrelated Donors
Menées à partir de données 2016-2020 portant sur 17 292 patients atteints d'une leucémie aiguë ou d'une tumeur myéloïde et ayant reçu une greffe de cellules souches hématopoïétiques issues d'un donneur non apparenté avec une incompatibilité sur un gène HLA (dont 1 523 ayant reçu du cyclophosphamide post-greffe pour prévenir une maladie du greffon contre l'hôte), ces études analysent l'association entre la non-concordance de classe I ou de classe II des gène HLA du donneur et du receveur et la survie globale des patients
Purpose: Access to allogeneic hematopoietic cell transplantation (HCT) remains limited among persons of non-European ancestry if human leukocyte antigen (HLA) matching is required. We evaluated whether post-transplant cyclophosphamide (PTCy)–based graft-versus-host disease (GVHD) prophylaxis improved HCT outcomes with HLA-matched unrelated donor (MUD) and mismatched unrelated donor (MMUD) HCT when compared with calcineurin inhibitor (CNI)–based prophylaxis. Methods: Three-year overall survival (OS) and GVHD-free, relapse-free survival (GRFS) were compared between adult recipients undergoing initial MUD or single HLA locus MMUD HCT with either PTCy- or CNI-based prophylaxis who were reported to the Center for International Blood and Marrow Transplant Research between 2017 and 2021. Results: Included were 10,025 HCT recipients (7,272 recipients of MUD with CNI, 1,681 MUD with PTCy, 613 MMUD with CNI, and 459 MMUD with PTCy) who underwent HCT for acute leukemia (70.9%) or myelodysplastic syndromes (29.2%). Median patient age was 60.7 years (range, 18.0-82.7) and median follow-up was 36.6 (range, 3.0-77.8) months. When compared with MUD HCT with PTCy, MMUD HCT with PTCy had similar OS (hazard ratio [HR], 0.96 [95% CI, 0.823 to 1.11]; P = .60) and GRFS (HR, 0.90 [0.79 to 1.02]; P = .1). When compared with MUD HCT with CNI, OS was improved after MUD HCT with PTCy (HR, 0.88 [0.80 to 0.96]; P = .004) and GRFS was improved with PTCy after either MUD (HR, 0.61 [0.57 to 0.66]; P < .0001) or MMUD (HR, 0.68 [0.60 to 0.76]; P < .0001) HCT. Benefit from PTCy was independent of patient ancestry. Global registry level analysis demonstrated that inclusion of MMUD increased donor availability regardless of recipient ancestry. Conclusion: Use of PTCy results in comparable OS and GRFS using either MUD or MMUD HCT, expanding access to HCT for patients from all racial and ethnic ancestry groups.