Graft-versus-host disease (GVHD) is one of the most serious complications following a bone marrow transplant. It occurs when donor immune cells recognise the patient’s tissues as foreign and attack them, triggering an inflammatory response. The chronic form of the disease causes inflammation and fibrosis that may affect organs such as the skin, joints, gastrointestinal tract, eyes, liver and lungs, leading to functional impairment, reduced quality of life and, in some cases, life-threatening complications.

For several years, Vall d’Hebron, together with centres worldwide, has been involved in research projects evaluating the efficacy and safety of ruxolitinib for the treatment of paediatric GVHD. In 2024, the results of the phase II REACH5 study were presented and proved encouraging. The team has recently published the final results of the study in the journal Haematologica, demonstrating the long-term benefits of this therapy.

The REACH5 study included 45 patients aged between 2 and 18 years with moderate to severe chronic GVHD following haematopoietic cell transplantation. All patients received at least one dose of ruxolitinib, adjusted according to age, and were followed up for a median of three years.

Overall, 84.4% of patients responded to treatment; 31.1% achieved a complete response and 53.3% achieved a partial response. Approximately 60% of responding patients maintained their response throughout the three-year study period. Overall survival was 74.9%.

The study also assessed the drug’s safety profile. The most common adverse events were cytopenias and infections, and no new safety signals were identified.

“Thanks to REACH5, we have confirmed the results previously observed over a longer follow-up period. We confirm that ruxolitinib is effective in children with chronic GVHD, regardless of prior corticosteroid treatment, and we have not identified any additional safety concerns beyond those already known”, explains Dr. Cristina Díaz de Heredia, Director of the Haematopoietic Progenitor Transplant Programme of the Paediatric Oncology and Haematology Department at Vall d’Hebron University Hospital and researcher in the Childhood Cancer and Blood Disorders group at the Vall d’Hebron Research Institute (VHIR). “Additionally, we observed that when ruxolitinib is used as first-line treatment, patients may achieve a complete response without corticosteroids”, she adds.

Based on these results, ruxolitinib is currently approved in the European Union for patients older than six months with chronic GVHD who have shown an inadequate response to first-line therapy. Further studies will be needed to assess its role as a first-line treatment.