Article
作者: Meinhardt, Andrea  ; Monti, Ilaria  ; Giannelli, Stefania  ; Bernardo, Maria Ester  ; Galicchio, Miguel  ; Meyts, Isabelle  ; Karakas, Zeynep  ; Silvani, Paolo  ; Baumann, Ulrich  ; Pituch-Noworolska, Anna  ; Gallo, Vera  ; Gabaldo, Michela  ; Consiglieri, Giulia  ; Migliavacca, Maddalena  ; Calbi, Valeria  ; Carlucci, Filippo  ; Finocchi, Andrea  ; Tommasini, Alberto  ; Casiraghi, Miriam  ; Guner, Sukru Nail  ; Di Serio, Clelia  ; Ferri, Chiara  ; Duse, Marzia  ; Darin, Silvia  ; Levi, Margherita  ; Zancan, Stefano  ; Montin, Davide  ; Tucci, Francesca  ; Barzaghi, Federica  ; Salerio, Federica Andrea  ; Pasquet, Marlène  ; Rabusin, Marco  ; Cancrini, Caterina  ; Leonardi, Lucia  ; Ferrua, Francesca  ; Cesana, Daniela  ; Sambuco, Maria  ; Aiuti, Alessandro  ; Ciceri, Fabio  ; Corti, Ambra  ; Fossati, Claudia  ; Pajno, Roberta  ; Cicalese, Maria Pia  ; Speckmann, Carsten  ; Ladogana, Saverio  ; AbdElaziz, Dalia  ; Dionisio, Francesca  ; Recupero, Salvatore  ; Porta, Fulvio  ; Notarangelo, Lucia Dora  ; Garella, Vittoria  ; Stepensky, Polina  ; Rancoita, Paola M V  ; Priolo, Alessio 
Adenosine deaminase (ADA) deficiency leads to severe combined immunodeficiency (SCID). Previous clinical trials showed that autologous CD34+ cell gene therapy (GT) following busulfan reduced-intensity conditioning is a promising therapeutic approach for ADA-SCID, but long-term data are warranted. Here we report an analysis on long-term safety and efficacy data of 43 patients with ADA-SCID who received retroviral ex vivo bone marrow-derived hematopoietic stem cell GT. Twenty-two individuals (median follow-up 15.4 years) were treated in the context of clinical development or named patient program. Nineteen patients were treated post-marketing authorization (median follow-up 3.2 years), and two additional patients received mobilized peripheral blood CD34+ cell GT. At data cutoff, all 43 patients were alive, with a median follow-up of 5.0 years (interquartile range 2.4-15.4) and 2 years intervention-free survival (no need for long-term enzyme replacement therapy or allogeneic hematopoietic stem cell transplantation) of 88% (95% confidence interval 78.7-98.4%). Most adverse events/reactions were related to disease background, busulfan conditioning or immune reconstitution; the safety profile of the real world experience was in line with premarketing cohort. One patient from the named patient program developed a T cell leukemia related to treatment 4.7 years after GT and is currently in remission. Long-term persistence of multilineage gene-corrected cells, metabolic detoxification, immune reconstitution and decreased infection rates were observed. Estimated mixed-effects models showed that higher dose of CD34+ cells infused and younger age at GT affected positively the plateau of CD3+ transduced cells, lymphocytes and CD4+ CD45RA+ naive T cells, whereas the cell dose positively influenced the final plateau of CD15+ transduced cells. These long-term data suggest that the risk-benefit of GT in ADA remains favorable and warrant for continuing long-term safety monitoring. Clinical trial registration: NCT00598481 , NCT03478670 .