Lentivector Iterations and Pre-Clinical Scale-Up/Toxicity Testing: Targeting Mobilized CD34 + Cells for Correction of Fabry Disease

• Published in: Molecular therapy. Methods & clinical development Vol. 5; no. C; pp. 241 - 258
• Main Authors: Huang, Ju, Khan, Aneal, Au, Bryan C, Barber, Dwayne L, López-Vásquez, Lucía, Prokopishyn, Nicole L, Boutin, Michel, Rothe, Michael, Rip, Jack W, Abaoui, Mona, Nagree, Murtaza S, Dworski, Shaalee, Schambach, Axel, Keating, Armand, West, Michael L, Klassen, John, Turner, Patricia V, Sirrs, Sandra, Rupar, C Anthony, Auray-Blais, Christiane, Foley, Ronan, Medin, Jeffrey A
• Format: Journal Article
• Language: English
• Published: United States Elsevier Limited 16.06.2017; American Society of Gene & Cell Therapy; Elsevier
• Subjects: Animal models; CD34 antigen; Cell culture; Enzymes; Expression vectors; Fabry's disease; FDA approval; Flow cytometry; Gene therapy; Genomes; GMP production; Good Manufacturing Practice; hematopoietic stem/progenitor cell; lysosomal storage disease; Males; Medical screening; Metabolism; Original; Patients; Toxicity testing; Transplantation; Xenografts; xenotransplantation; α-galactosidase A; xenotransplantation; α-galactosidase A; hematopoietic stem/progenitor cell; lysosomal storage disease; GMP production
• ISSN: 2329-0501; 2329-0501
• DOI: 10.1016/j.omtm.2017.05.003

Fabry disease is a rare lysosomal storage disorder (LSD). We designed multiple recombinant lentivirus vectors (LVs) and tested their ability to engineer expression of human α-galactosidase A (α-gal A) in transduced Fabry patient CD34 hematopoietic cells. We further investigated the safety and efficacy of a clinically directed vector, LV/AGA, in both ex vivo cell culture studies and animal models. Fabry mice transplanted with LV/AGA-transduced hematopoietic cells demonstrated α-gal A activity increases and lipid reductions in multiple tissues at 6 months after transplantation. Next we found that LV/AGA-transduced Fabry patient CD34 hematopoietic cells produced even higher levels of α-gal A activity than normal CD34 hematopoietic cells. We successfully transduced Fabry patient CD34 hematopoietic cells with "near-clinical grade" LV/AGA in small-scale cultures and then validated a clinically directed scale-up transduction process in a GMP-compliant cell processing facility. LV-transduced Fabry patient CD34 hematopoietic cells were subsequently infused into NOD/SCID/Fabry (NSF) mice; α-gal A activity corrections and lipid reductions were observed in several tissues 12 weeks after the xenotransplantation. Additional toxicology studies employing NSF mice xenotransplanted with the therapeutic cell product demonstrated minimal untoward effects. These data supported our successful clinical trial application (CTA) to Health Canada and opening of a "first-in-the-world" gene therapy trial for Fabry disease.