Novel Treatment for Graft-versus-Host Disease.

Allogeneic hematopoietic cell transplantation is a curative therapy for a variety of hematological diseases, but its success is hampered by acute and chronic graft-versus-host disease (GvHD). In the last five years, multiple novel therapeutic approaches for GvHD have entered the arena. The National Institutes of Health consensus criteria for chronic GvHD have set standards for designing and reporting clinical trials, and preclinical experiments of chronic GvHD have revealed the central roles of regulatory T cells, B-cell signaling, Th17 cells, Tc17 cells, follicular helper T cells, follicular regulatory T cells, and fibrosis-promoting factors. These scientific efforts and the resulting clinical studies led to the approval of ibrutinib, belumosudil and ruxolitinib for the treatment of refractory chronic GvHD. Recently, large randomized phase III trials showed that ruxolitinib was superior to the best available therapy for glucocorticoid-refractory acute GvHD (REACH2 trial) and glucocorticoid-refractory chronic GvHD (REACH3 trial). Furthermore, novel regenerative approaches, including IL-22, R-spondin, and glucogon-like peptide-2, and cellular therapies, such as the transfer of mesenchymal stem cells and regulatory T cells, are under intensive investigation. GvHD prevention using abatacept, dipeptidyl peptidase 4 inhibition, and post-transplant cyclophosphamide are also promising strategies that require further evaluation. In this article, we summarize the emerging knowledge of acute GvHD, chronic GvHD, and preclinical and clinical data of mesenchymal stem cells as GvHD therapy. In the next five years, basic and clinical studies will further advance the field, and dramatic changes in GvHD management will be encountered.