New hopeful treatment for children with a rare disease

Helene Decaluwe

Credit: CHU Sainte-Justine Research Center

Led by clinical researcher Hélène Decaluwe, from the CHU Sainte-Justine, a team has developed a treatment that slows the progression of a rare disease that attacks the immune system of children. The scientific article describing this new treatment was published at the beginning of January in the Journal of Allergy and Clinical Immunology.

The success of the DreDecaluwe, also a professor in the Department of Pediatrics at the University of Montreal, is due to the combination of two classes of drugs that work in synergy to reduce the progression of a rare immune disease. Currently, about one-third of patients do not respond adequately to treatment and die within five years of diagnosis.

“We have to try to do better. It is a very serious disease which is one of the immunological emergencies to be treated as quickly as possible, ”explains the doctor.

Familial hemophagocytic lymphohistiocytosis (FHL) affects children from birth. It is an immune system abnormality that takes the form of a cytokine storm. A serious inflammatory reaction ensues, because the cytokines, these messenger proteins, send disorderly signals to the immune system.

Curb LHF to transplant stem cells

To cure LHF, a stem cell transplant is necessary. However, it is essential that the progression of the disease be slowed down before proceeding with a transplant. For some patients, traditional treatments to bridge the transplant only partially work and do not prevent a resurgence of the disease. In addition, these treatments create a significant toxicity problem.

Thanks to this new study, the DreDecaluwe achieved complete control of the disease in a mouse model with no overt toxicity. The cytokine storm was calmed with the use of the new drug duo.

“These are very promising results, which could ultimately save and cure a greater number of children suffering from this immune disease,” says Hélène Decaluwe.

What’s even more exciting is that these drugs (emapalumab and ruxolitinib) are already individually approved for use in humans. The next step will be to study the effectiveness of the “bridge treatment” in a clinical study. “This confirms the leadership role of the CHU Sainte-Justine in the management of this disease,” she adds.

The results of this study offer hope to greatly improve the cure rate of children with FHL by allowing them to wait until the stem cell transplant.

About this study

The article “Combined IFNγ and JAK inhibition to treat hemophagocytic lymphohistiocytosis in mice”, by Josée-Anne Joly, Alexis Vallée, Benoite Bourdin, Sara Bourbonnais, Natalie Patey, Louis Gaboury, Yves Théorêt and Hélène Decaluwe, was published on January 4 2023 in the Journal of Allergy and Clinical Immunology.

Funding for the study was provided by the Charles-Bruneau Foundation and the Canadian Institutes of Health Research.