Ruxolitinib for the treatment of pediatric acute and chronic steroid-refractory graft-versus-host disease: Efficacy, safety, and outcomes.

Steroid-refractory graft-versus-host disease (SR-GVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Ruxolitinib is food and drug administration (FDA) approved for patients ≥12 years, but data remain limited in other pediatric cohorts. This single-center retrospective study evaluated 77 acute (51% grades III-IV) and 45 chronic (82% severe) SR-GVHD patients under 18 years of age (range 0-17). The overall response rate (ORR) was 83% and 87% in patients with acute and chronic SR-GVHD, respectively. The organ-specific ORRs in chronic SR-GVHD for the skin, gastrointestinal (GI) tract, liver, oral mucosa, eyes, lungs, joints, and genitalia were 71%, 83%, 88%, 56%, 52%, 37%, 42%, and 40%, respectively. Three-year overall survival was 70% (acute) and 85% (chronic). By 3 years, 43% of chronic and 60% of acute patients discontinued all immunosuppression. Age < 12 years did not affect outcomes (acute ORR: 78% vs. 76%, P = 0.96; chronic ORR: 89% vs. 79%, P = 0.14). Hematological toxicity was the main adverse event. The initial ruxolitinib dose correlated with hematologic toxicity and liver function test elevations in chronic GVHD. These results support the efficacy and safety of ruxolitinib across pediatric age groups, though further prospective studies are needed to optimize dosing and long-term monitoring.