Inflammatory cytokines play an important role in the development of graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation. However, blocking a single cytokine fails to improve the dismal prognosis of patients with GVHD. Jak inhibitors block the signaling of many cytokines relevant to GVHD. Retrospective studies suggest that Jak1/2 inhibitor ruxolitinib could be effective in patients with steroid-refractory GVHD, but has adverse effects such as cytopenia, susceptibility to infection, and withdrawal syndrome. Currently, prospective studies evaluating the efficacy of ruxolitinib and a selective Jak1 inhibitor are in progress.
2017 The Japan Society for Hematopoietic Stem Cell Transplantation