Impact of donor type on the outcomes of acute graft versus host disease to systemic corticosteroid therapy.

Systemic corticosteroid therapy is a well-established first-line treatment for grades II-IV acute graft-versus-host disease (aGVHD). Recently, several developments have occurred, including the introduction of transplantation from human leukocyte antigen (HLA) haploidentical donors using post-transplant cyclophosphamide (PTCY-Haplo), and improvements in prognosis after cord blood transplantation (CBT) in Japan. This study aimed to analyze the association between donor sources and outcomes in patients with aGVHD. Our study included 2732 patients who developed grades II-IV aGVHD, and were treated with systemic corticosteroids. We compared HLA-matched related donors (MRD), HLA-matched unrelated donors (MUD), PTCY-Haplo, and CBT. We set endpoint as response rate, 1-year cumulative incidence of non-relapse mortality (NRM), and overall survival (OS). The adjusted odds ratios for a complete response (CR) were 0.99 (95% confidence interval [CI]: 0.74-1.31, P = 0.925) for MUD, 2.08 (95% CI: 1.35-3.25, P = 0.001) for PTCY-Haplo, and 1.08 (95% CI: 0.83-1.41, P = 0.550) for CBT compared with MRD. A significant increase in response rates for PTCY were only found in a single-organ involvement. No significant association was observed between the donor source and NRM or OS. In conclusion, PTCY-Haplo is associated with a high response rate in patients with a single-organ aGVHD; however, MUD and CBT were not associated with treatment response.