Lentiviral (LV) Gene Therapy for Adenosine Deaminase (ADA) Deficiency

This is a historically controlled, non-randomized Phase I/II clinical trial to assess the safety and efficacy of autologous transplantation of CD34+ hematopoietic stem/progenitor cells (HSPCs), obtained from infants affected by ADA-SCID, following transduction of the HSPCs with a lentiviral vector (LV) carrying the human ADA complementary DNA (cDNA) under the control of the elongation factor 1 alpha shortened (EFS) promoter. Subjects treated in the trial receive the infusion of autologous, transduced cells following marrow cytoreduction with busulfan. The outcomes are compared to those observed in a historical control group of patients who received an allogeneic hematopoietic stem cell transplant (HSCT). This Phase I/II clinical trial will be performed at Great Ormond Street Hospital (GOSH), London, United Kingdom.