Retrospective single center analysis of outcome, risk factors and therapy in steroid refractory graft-versus-host disease after allogeneic hematopoietic cell transplantation.

Acute and chronic graft-vs.-host disease (aGvHD and cGvHD) are major complications after allogeneic hematopoietic cell transplantation (HCT) leading to substantial morbidity and mortality. This retrospective single-center study analyzes incidence, therapy, and outcome of GvHD in n = 721 patients ≥18 years having received allogeneic HCT 2004-2013 with a special focus on steroid refractory GvHD. Acute (n = 355/49.2%) and chronic (n = 269/37.3%) GvHD were mainly treated by steroids in first-line therapy. The proportion of steroid refractory aGvHD and cGvHD was 35.7% and 31.4%, respectively. As there is no standard therapy for steroid refractory GvHD, a range of different agents was used. In aGvHD, the overall response rate (ORR) of steroid refractory GvHD to second-line treatment was 27.4%. Mycophenolate mofetil (MMF) and mTOR inhibitors led to superior response rates (ORR 50.0% and 53.3%, respectively). In steroid refractory cGvHD therapy, ORR was 44.4%. Use of calcineurin inhibitors (CNI; n = 11/45.5%), MMF (n = 18/50.0%), mTOR inhibitors (n = 10/60.0%), and extracorporeal photophoresis (ECP; n = 16/56.3%) showed ORR above average. Targeted therapies lead to responses in 7.7% (n = 13). This data may help to improve the design of future prospective clinical studies in GvHD.