Initial results from a first-in-human gene therapy trial on X-linked retinitis pigmentosa caused by mutations in RPGR
Jasmina Cehajic-Kapetanovic, Kanmin Xue, Cristina Martinez-Fernandez de la Camara, Anika Nanda, Alexandra Davies, Laura J Wood, Anna Paola Salvetti, M Dominik Fischer, James W Aylward, Alun R Barnard, Jasleen K Jolly, Edmond Luo, Brandon J Lujan, Tuyen Ong, Aniz Girach, Graeme C M Black, Ninel Z Gregori, Janet L Davis, Potyra R Rosa, Andrew J Lotery, Byron L Lam, Paulo E Stanga, Robert E MacLaren, Jasmina Cehajic-Kapetanovic, Kanmin Xue, Cristina Martinez-Fernandez de la Camara, Anika Nanda, Alexandra Davies, Laura J Wood, Anna Paola Salvetti, M Dominik Fischer, James W Aylward, Alun R Barnard, Jasleen K Jolly, Edmond Luo, Brandon J Lujan, Tuyen Ong, Aniz Girach, Graeme C M Black, Ninel Z Gregori, Janet L Davis, Potyra R Rosa, Andrew J Lotery, Byron L Lam, Paulo E Stanga, Robert E MacLaren
Abstract
Retinal gene therapy has shown great promise in treating retinitis pigmentosa (RP), a primary photoreceptor degeneration that leads to severe sight loss in young people. In the present study, we report the first-in-human phase 1/2, dose-escalation clinical trial for X-linked RP caused by mutations in the RP GTPase regulator (RPGR) gene in 18 patients over up to 6 months of follow-up (https://ichgcp.net/clinical-trials-registry/NCT03116113" title="See in ClinicalTrials.gov">NCT03116113). The primary outcome of the study was safety, and secondary outcomes included visual acuity, microperimetry and central retinal thickness. Apart from steroid-responsive subretinal inflammation in patients at the higher doses, there were no notable safety concerns after subretinal delivery of an adeno-associated viral vector encoding codon-optimized human RPGR (AAV8-coRPGR), meeting the pre-specified primary endpoint. Visual field improvements beginning at 1 month and maintained to the last point of follow-up were observed in six patients.
Conflict of interest statement
Competing Interest
R.E.M. scientific cofounder of Nightstar Therapeutics Inc. (now owned by Biogen Inc.); R.E.M., G.C.M.B. scientific advisors to the UK National Health Service National Institute for Health and Care Excellence (NICE) in relation to retinal gene therapy; M.D.F., B.L.L., B.J.L., R.E.M. consulting or on advisory board for Biogen Inc.; R.E.M., M.D.F. named inventors on the patent relating to codon-optimised RPGR gene therapy owned by the University of Oxford (US20180273594A1, originally filed 2015-09-10). M.D.F., G.C.M.B., R.E.M. scientific advisory board to Novartis; E.L., T.O., A.G. were employees of the sponsor of the trial, Nightstar Therapeutics (now Biogen Inc). The views expressed are those of the authors and not necessarily those of the National Health Service, the NIHR or the UK Department of Health.
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Source: PubMed