Use of belumosudil for the treatment of chronic graft-versus-host disease

Chronic graft-versus-host disease (cGVHD) is one of the most significant late complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT). First-line therapy is based on glucocorticosteroids; however, a substantial proportion of patients develop steroid-refractory disease requiring subsequent lines of treatment. In recent years, targeted therapies have been introduced into clinical practice, including belumosudil, a selective ROCK2 inhibitor. Aim : to evaluate the efficacy and safety of belumosudil in patients with severe steroid-refractory cGVHD. Main findings. In the presented case series, patients with severe cGVHD with lung involvement, refractory to glucocorticosteroids and prior therapies (including JAK inhibitors, antifibrotic, and immunomodulatory agents), received belumosudil as thirdor later-line treatment. Partial response was achieved in one patient, while disease stabilization was observed in two patients. In all cases, the treatment demonstrated a favorable safety profile, with no serious adverse events requiring discontinuation. These findings suggest that belumosudil is clinically effective in heavily pretreated patients, including those with advanced pulmonary involvement. However, the limited reversibility of fibrotic changes supports the rationale for earlier initiation of therapy.