Promising Gene Therapy Successfully Treats Children with Rare Disorder

An experimental gene therapy has successfully treated dozens of children suffering from a rare and potentially fatal immune disorder known as adenosine deaminase-deficient severe combined immunodeficiency (ADA-SCID). The study, which involved 62 children, offers a hopeful indication that this debilitating condition could be overcome in the future.

ADA-SCID is caused by genetic mutations that prevent the proper functioning of the immune system, leaving affected children highly susceptible to infections. Without treatment, the condition is often fatal within the first two years of life. Current therapeutic options are not only costly but also carry significant risks.

The new treatment approach entails harvesting a child’s blood stem cells, which are responsible for generating immune cells. Researchers then employ a virus to deliver a healthy copy of the ADA gene into these cells. Once corrected, the cells are infused back into the patient, enabling them to produce healthy immune cells. According to the researchers, it typically takes between six to twelve months for the immune system to normalize following the procedure.

Between 2012 and 2019, 59 of the participating patients received the gene therapy, with their immune functions remaining stable and free from severe complications since then. Remarkably, five of these children have maintained their health for over a decade.

Significant Findings and Expert Insights

The findings of this study, published in the New England Journal of Medicine, represent the largest and longest follow-up of a gene therapy for ADA-SCID to date. Dr. Donald Kohn, a paediatric bone marrow transplant physician at the University of California, Los Angeles, who co-developed the treatment alongside UK scientists, stated, “These results are what we hoped for when we first began developing this approach.”

Most side effects experienced by the children were mild to moderate and primarily related to standard procedures rather than the gene therapy itself. In three instances where the therapy was ineffective, those patients were able to revert to conventional treatment options without significant issues.

Notably, the study found that more than half of the children received stem cells that had been frozen, demonstrating outcomes comparable to those who received fresh cells. This suggests that the therapy could be more readily accessible to patients globally. Dr. Katelyn Masiuk, another author of the study, emphasized, “This removes the need for patients and their families to travel long distances to specialist centres.”

Looking Ahead: Regulatory Approval and Real-World Impact

The research team now plans to pursue regulatory approval from the US Food and Drug Administration (FDA) and is collaborating with commercial partners to facilitate the treatment’s availability. Dr. Kohn expressed optimism that the gene therapy could be publicly accessible within the next two to three years.

The experimental treatment has already had life-altering effects for children like Eliana Nachem, an 11-year-old girl from Virginia. Diagnosed with ADA-SCID at just three months old in 2014, Eliana’s family took extreme measures to protect her from infections, such as removing pets from their home and using air filters constantly.

Eliana underwent the experimental gene therapy at ten months old. After some early complications, she has since made a full recovery and is enjoying a normal childhood. Her mother, Caroline, reflected on the experience, stating, “I remember thinking, she’s born again, and now we just get to watch her grow.”

This innovative gene therapy represents a groundbreaking advancement in the treatment of ADA-SCID, providing hope for children and families affected by this rare disorder.