An experimental gene therapy has shown lasting success in treating dozens of children born with a rare and often fatal immune disorder known as ADA-SCID. The condition is caused by a genetic mutation that prevents the body from producing a working immune system, leaving infants extremely vulnerable to infections.
Severe combined immunodeficiency (SCID) due to adenosine deaminase (ADA) deficiency (ADA-SCID) is a life-threatening inborn error of immunity for which lentiviral gene therapy has been investigated in clinical trials.
Without treatment, most do not survive beyond early childhood.
In the new therapy, doctors collect a child’s blood stem cells and insert a healthy copy of the ADA gene using a harmless virus. The corrected cells are then infused back into the patient, allowing the body to start producing normal immune cells.
The long-term study, published in the New England Journal of Medicine, followed 62 children treated between 2012 and 2019. Of them, 59 developed stable immune systems and have remained healthy — including five children who are still doing well more than ten years later.
Side effects were generally mild, and similar results were achieved even when frozen stem cells were used, suggesting the therapy could be offered more widely without the need for families to travel to specialised centres.
Researchers are now preparing to seek approval from the US Food and Drug Administration, aiming to make the therapy available within the next few years.
