Potential clinical benefits of early belumosudil treatment in chronic graft-versus-host disease

Objectives Administering belumosudil before chronic graft-versus-host disease (cGVHD) fibrosis progresses may improve response rates. Nonetheless, clear evidence is lacking regarding the effects of treatment timing or history on response to belumosudil. We examined the effects of early belumosudil treatment in cGVHD.Study design This retrospective cohort study identified 23 patients who received belumosudil for cGVHD at The University of Osaka Hospital from May 2024 to January 2026. The median time from cGVHD onset to belumosudil initiation was 228 days. Fourteen patients received belumosudil early, within 1 year of cGVHD onset, and fourteen received it as second-line therapy.Results At the patient level, the overall response rate was 85.7% in the early-treatment group and 50.0% in the late-treatment group, but the difference was not statistically significant (p = 0.137). In the exploratory organ-level analysis, early treatment was associated with significant improvement in cGVHD scores compared with late treatment. No significant differences in response were observed between second-line and later-line therapy.Conclusions Although these findings are at the organ level, this study suggests that, regardless of prior treatment, early administration of belumosudil following the onset of cGVHD may be associated with improved response.