[Ruxolitinib for treatment of GvHD in patients with myelofibrosis].

Graft-versus-host-disease (GvHD) is a major complication and leading cause of non-relapse mortality after allogeneic hematopoietic stem cell transplantation. Corticosteroids remain the standard initial therapy for GvHD; however, patients frequently become steroid-refractory (SR) or remain steroid dependent. Cytokine inhibition appears to be a potential option; however, blockade of any single cytokine may not be sufficient probably because of the redundant effects of multiple cytokines. The Jak1/2 inhibitor ruxolitinib can simultaneously inhibit the signaling pathway of multiple cytokines with relevance for GvHD, such as interferon (IFN-γ), IL-2, and IL-6. A recent retrospective survey reported that ruxolitinib produced a high response rate for SR-GvHD, leading to better survival odds. A prompt and sustained ruxolitinib response contributes to the steroid-sparing effect; however, accumulating evidence showed that ruxolitinib exerts substantial myelosuppression and immunosuppressive activity in patients with myelofibrosis (MF). Additionally, serious adverse events following discontinuation of ruxolitinib treatment, characterized by acute relapse of the disease and/or GvHD, have been recognized. Herein we discuss the advantages and disadvantages of ruxolitinib as treatment for GvHD in patients with MF.