Overview

• Researchers report long-term immune reconstitution in 59 of 62 treated children, who remain off enzyme replacement therapy after a single autologous lentiviral infusion.
• The cohort treated between 2012 and 2019 has accrued about 474 patient‑years of follow-up, including five children healthy for more than a decade.
• No serious adverse events were attributed to the gene modification itself, with most side effects linked to conditioning chemotherapy and preparatory procedures.
• Three treatment failures returned to standard care, including two bone marrow transplants and one child on enzyme therapy preparing for transplant at data cutoff.
• More than half of patients received cryopreserved corrected stem cells with outcomes comparable to fresh cells, supporting centralized manufacturing and wider access; the program is licensed to Rarity PBC to pursue pharmaceutical-grade production and U.S. approval.