An experimental gene therapy developed by UCLA, University College London, and Great Ormond Street Hospital has successfully restored immune function in 59 of 62 children born with ADA-SCID, a rare and life-threatening genetic immune disorder. ADA-SCID, caused by mutations in the ADA gene, leaves children highly vulnerable to infections, often proving fatal within the first two years of life if untreated.
Unlike standard treatments such as bone marrow transplants or weekly enzyme injections, the therapy uses a child’s own stem cells, modified with a healthy ADA gene, to rebuild a functioning immune system. Immune recovery begins shortly after reinfusion and typically reaches normal levels within six to twelve months.
Long-term follow-up of patients treated between 2012 and 2019 shows stable, durable immune function with minimal side effects. The study represents the largest and longest follow-up for this type of gene therapy, including patients treated over a decade ago.
The therapy also works with frozen stem cells, increasing accessibility and allowing better quality control and dosing. UCLA researchers, supported by the California Institute for Regenerative Medicine, are now preparing for FDA approval, with commercial partners set to manufacture the therapy under pharmaceutical standards.
https://www.nejm.org/doi/full/10.1056/NEJMoa2502754