Overview

• New England Journal of Medicine data from 62 children treated between 2012 and 2019 show 100% survival with an average 7.5 years of follow-up, including five patients past a decade.
• The one-time, ex vivo lentiviral approach modifies a child’s own blood stem cells and typically restores normal immune function within six to twelve months.
• Immune function was durably reconstituted in 59 of 62 patients, allowing discontinuation of enzyme replacement and, for most, immunoglobulin therapy, with normal responses to routine vaccines.
• No treatment-limiting complications attributable to the gene therapy were reported; three non-responders returned to standard care, including bone marrow transplantation.
• Outcomes with frozen cell products matched fresh preparations, supporting local collection with centralized manufacturing as investigators and Rarity PBC prepare FDA submissions and UK partners explore market authorization.