Successful treatment of joint and fascial chronic graft-versus-host disease with baricitinib

Dear Editor, Chronic graft-vs-host disease (cGVHD) is a major late complication of allogeneic hematopoietic cell transplantation (HCT) occurring in ∼30–50% of transplant survivors. Joint and fascial manifestations of cGVHD such as joint stiffness, restricted range of motion (ROM), arthralgia and arthritis or synovitis are relatively common and cause significant functional impairment that compromises the quality of life. CSs are the first-line drug for treating joint and fascial cGVHD. However, their therapeutic effect is often partial, and treating steroid-resistant cGVHD is challenging. Here, we report two patients with steroid-resistant joint and fascial cGVHD successfully treated with baricitinib, a selective Janus-activated kinase (JAK)1 and JAK2 inhibitor. Patient 1 was a 19-year-old Japanese male who underwent allogeneic HCT for X linked inhibitor of apoptosis protein (XIAP) deficiency. He had a medical history of recurrent episodes of hemophagocytic lymphohistiocytosis from the age of 1 year and IBD at the age of...