Treatment of steroid-refractory acute/chronic graft versus host disease: A single-center real-world experience of ruxolitinib in combination with extracorporeal photopheresis in a high-risk population.

Steroid-refractory acute and chronic graft-versus-host disease (SR-a/cGvHD) represents a potential life-threatening complication following allogeneic stem-cell transplantation (allo-SCT). The JAK1/2-inhibitor ruxolitinib and the extracorporeal photopheresis (ECP) have been shown to significantly improve the overall response rate (ORR) in this setting. However, about 30-40 % of high-risk patients do not respond to monotherapy and/or experience side effects. Considering the potential synergic mechanism of action of ruxolitinib and ECP and the good safety profile, we decided to investigate the role of a treatment strategy of ruxolitinib in combination with ECP in frail patients with high-risk SR-a/cGvHD. We conducted a retrospective single-center study comprising 47 patients who underwent allo-SCT from November 2018 to October 2023 and received treatment for SR-aGvHD (n=20) or SR-cGvHD (n=27) with ruxolitinib and ECP. In the SR-aGvHD group, 95 % of patients had a lower GI-tract involvement, with 80 % presenting with a grade III-IV SR-aGvHD. The ORR at day +28 was 65 %, with a 30 % CR rate. The 1-year overall survival (OS) for responders (PR and CR) was 33 % (95 % CI, 10 %-59 %). In the SR-cGvHD group, 55.6 % and 44.4 % had moderate and severe SR-cGvHD, respectively. The majority of patients (66.7 %) had a GI-involvement. The ORR at week 24 was 88 %, including 12 % CR and 76 % PR. The 1-year OS for responders was 76 % (95 % CI, 47 %-90 %). Our retrospective analysis shows that the treatment of ruxolitinib in combination with ECP has potential efficacy in patients with SR-a/cGvHD with a high-risk for transplantation-associated mortality.