Good Laboratory Practice Preclinical Safety Studies for GSK2696273 (MLV Vector-Based Ex Vivo Gene Therapy for Adenosine Deaminase Deficiency Severe Combined Immunodeficiency) in NSG Mice.
GSK2696273 (autologous CD34+ cells transduced with retroviral vector that encodes for the human adenosine deaminase [ADA] enzyme) is a gamma-retroviral ex vivo gene therapy of bone marrow-derived CD34+ cells for the treatment of adenosine deaminase deficiency severe combined immunodeficiency (ADA-SCID). ADA-SCID is a severe monogenic disease characterized by immunologic and nonimmunologic symptoms. Bone-marrow transplant from a matched related donor is the treatment of choice, but it is available for only a small proportion of patients. Ex vivo gene therapy of patient bone-marrow CD34+ cells is an alternative treatment. In order to prepare for a marketing authorization application in the European Union, preclinical safety studies in mice were requested by the European Medicines Agency (EMA). A pilot study and a main biodistribution study were performed according to Good Laboratory Practice (GLP) at the San Raffaele Telethon Institute for Gene Therapy test facility. In the main study, human umbilical cord blood (UCB)-derived CD34+ cells were transduced with gamma-retroviral vector used in the production of GSK2696273. Groups of 10 male and 10 female NOD-SCID gamma (NSG) mice were injected intravenously with a single dose of transduced- or mock-transduced UCB CD34+ cells, and they were observed for 4 months. Engraftment and multilineage differentiation of blood cells was observed in the majority of animals in both groups. There was no significant difference in the level of chimerism between the two groups. In the gene therapy group, vector was detectable in lymphohemopoietic and nonlymphohemopoietic tissues, consistent with the presence of gene-modified human hematopoietic donor cells. Given the absence of relevant safety concerns in the data, the nonclinical studies and the clinical experience with GSK2696273 supported a successful application for market authorization in the European Union for the treatment of ADA-SCID patients, for whom no suitable human leukocyte antigen-matched related donor is available.
1 Pathogenesis and Therapy of Primary Immunodeficiencies Unit, San Raffaele Telethon Institute for Gene Therapy (SR-TIGET) , IRCCS San Raffaele Scientific Institute, Milan, Italy.|2 GLP SR-TIGET Test Facility , Ospedale San Rafaele, Milan, Italy.
Nicola
N
Carriglio
3 GlaxoSmithKline, In Vitro In Vivo Translation, Ware, United Kingdom.
Jan
J
Klapwijk
1 Pathogenesis and Therapy of Primary Immunodeficiencies Unit, San Raffaele Telethon Institute for Gene Therapy (SR-TIGET) , IRCCS San Raffaele Scientific Institute, Milan, Italy.|2 GLP SR-TIGET Test Facility , Ospedale San Rafaele, Milan, Italy.
Raisa Jofra
RJ
Hernandez
2 GLP SR-TIGET Test Facility , Ospedale San Rafaele, Milan, Italy.
Michela
M
Vezzoli
3 GlaxoSmithKline, In Vitro In Vivo Translation, Ware, United Kingdom.
Franck
F
Chanut
3 GlaxoSmithKline, In Vitro In Vivo Translation, Ware, United Kingdom.
Rhiannon
R
Lowe
1 Pathogenesis and Therapy of Primary Immunodeficiencies Unit, San Raffaele Telethon Institute for Gene Therapy (SR-TIGET) , IRCCS San Raffaele Scientific Institute, Milan, Italy.|2 GLP SR-TIGET Test Facility , Ospedale San Rafaele, Milan, Italy.
Elena
E
Draghici
4 GlaxoSmithKline, Regulatory Affairs, King of Prussia, Pennsylvania.
Melanie
M
Nord
2 GLP SR-TIGET Test Facility , Ospedale San Rafaele, Milan, Italy.
Paola
P
Albertini
2 GLP SR-TIGET Test Facility , Ospedale San Rafaele, Milan, Italy.|3 GlaxoSmithKline, In Vitro In Vivo Translation, Ware, United Kingdom.
Patrizia
P
Cristofori
3 GlaxoSmithKline, In Vitro In Vivo Translation, Ware, United Kingdom.
Jane
J
Richards
5 Covance Laboratories Ltd , Harrogate, United Kingdom.
Hazel
H
Staton
3 GlaxoSmithKline, In Vitro In Vivo Translation, Ware, United Kingdom.
Jonathan
J
Appleby
1 Pathogenesis and Therapy of Primary Immunodeficiencies Unit, San Raffaele Telethon Institute for Gene Therapy (SR-TIGET) , IRCCS San Raffaele Scientific Institute, Milan, Italy.|6 Vita-Salute San Raffaele University , Milan, Italy.
Alessandro
A
Aiuti
1 Pathogenesis and Therapy of Primary Immunodeficiencies Unit, San Raffaele Telethon Institute for Gene Therapy (SR-TIGET) , IRCCS San Raffaele Scientific Institute, Milan, Italy.|2 GLP SR-TIGET Test Facility , Ospedale San Rafaele, Milan, Italy.
Aisha V
AV
Sauer
D000243:Adenosine Deaminase / Q000172:deficiency* / Q000235:genetics; D000361:Agammaglobulinemia / Q000235:genetics / Q000628:therapy*; D000818:Animals; D004353:Drug Evaluation, Preclinical; D005260:Female; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000627:therapeutic use*; D006801:Humans; D007753:Laboratories / Q000592:standards*; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D016511:Severe Combined Immunodeficiency / Q000235:genetics / Q000628:therapy*; D014018:Tissue Distribution
C548482:ADA protein, human; D000243:Adenosine Deaminase
ADA-SCID; GLP; adenosine deaminase; biodistribution; gene therapy; retroviral vector