ADA-SCID

Overview

Adenosine deaminase deficiency causing severe combined immunodeficiency; treated by the first hematopoietic stem cell gene therapy approved globally, with 50 patients treated, all alive, and durable immune reconstitution confirmed at 10-15+ years. ADA-SCID gene therapy was the first hematopoietic stem cell gene therapy approved in the world; 50 patients were treated with all alive, showing immune reconstitution and infection protection with durable benefits persisting 10 to 15 years or more. Regulatory approval for ADA-SCID gene therapy was achieved with only 18 patients, establishing that rare disease gene therapies can receive marketing authorization with very small patient cohorts when clinical evidence is robust and regulators are engaged early. (Segment 2 (05:00-10:00)) ADA-SCID was the first disease treated at San Raffaele with engineered CD34 cells using a new gene transfer method; the addition of chemotherapy conditioning to make space in the bone marrow was the key breakthrough that made the gene therapy effective. The first ADA-SCID patient treated at San Raffaele was a Palestinian girl treated in collaboration with Israeli doctors, who is now 25 years old and thriving — demonstrating durable long-term efficacy of CD34 gene therapy for this immunodeficiency. (Segment 6 (25:00-30:00))