A new study conducted by the Pediatric Cancer and Hematological Diseases Research Group at Vall d’Hebron Institute of Research (VHIR) has demonstrated that the drug Ruxolitinib, already used in adults, is also effective and safe for treating paediatric patients with acute graft-versus-host disease (aGVHD).

The aGVHD occurs when a person receives a bone marrow or hematopoietic stem cell transplant and the donor’s new immune system attacks the recipient's body. Symptoms can include skin rashes, liver damage, and severe gastrointestinal problems, potentially leading to significant morbidity and, in extreme cases, death.

The study, named REACH4, is published in Blood, from the American Society of Hematology (NCT03491215). It is particularly important as it focuses on paediatric patients who had not received prior treatment or had not responded to steroids, the standard treatment for this condition. The research was conducted across multiple medical centres, allowing for a broader evaluation of the results. Ruxolitinib was administered based on age: patients aged 12 to 18 received 10 mg twice daily, those aged 6 to 12 received 5 mg twice daily, and those aged 2 to 6 received 4 mg twice daily.

The results of the REACH4 study are positive and promising. The doses administered to the different age groups were confirmed to be effective. Additionally, the overall response rate was 84.4% of patients on day 28 and 66.75% on day 56, indicating that the majority of patients achieved significant improvement, regardless of age group or previous steroid treatment. Furthermore, Ruxolitinib’s effect was shown to be durable.

The most common adverse effects observed were anaemia, decreased neutrophil count, and a reduced overall white blood cell count. No other adverse effects were noted beyond those already observed with Ruxolitinib in other populations. This suggests that Ruxolitinib is a safe treatment for these patients.

“The aGVHD is a devastating complication that can limit treatment options for children who have received a bone marrow transplant. The fact that Ruxolitinib has shown such high efficacy in this study is a significant breakthrough in the treatment of this disease in paediatrics,” says Dr. Cristina Díaz de Heredia Rubio, Head of the Paediatric Oncology and Haematology Section and Director of the Hematopoietic Stem Cell Transplant Program at Vall d’Hebron University Hospital and principal investigator of the REACH4 study conducted by VHIR.

Although the results offer new hope for parents and families facing aGVHD in paediatric patients, further studies will be needed for approval.