title: Oral 9-cis retinoid for childhood blindness due to Leber congenital amaurosis caused by RPE65 or LRAT mutations: an open-label phase 1b trial.
abstract: BACKGROUND
  Leber congenital amaurosis, caused by mutations in RPE65 and LRAT, is a severe form of inherited retinal degeneration leading to blindness. We aimed to assess replacement of the missing chromophore 11-cis retinal with oral QLT091001 (synthetic 9-cis-retinyl acetate) in these patients.
  
  
  METHODS
  In our open-label, prospective, phase 1b trial, we enrolled patients (aged ≥6 years) with Leber congenital amaurosis and RPE65 or LRAT mutations at McGill University's Montreal Children's Hospital. Patients received 7 days of oral QLT091001 (10-40 mg/m(2) per day). We assessed patients at baseline and days 7, 9, 14, and 30, and then 2 months and every 2 months thereafter for up to 2·2 years for safety outcomes and visual function endpoints including Goldmann visual fields (GVF), visual acuity, and functional MRI assessment. We regarded patients as having an improvement in vision if we noted at least a 20% improvement in retinal area on GVF compared with baseline or a visual acuity improvement of five or more letters compared with baseline in two consecutive study visits (or any improvement from no vision at baseline). This study is registered with ClinicalTrials.gov, number NCT01014052.
  
  
  RESULTS
  Between December, 2009, and June, 2011, we enrolled and treated 14 patients aged 6-38 years who were followed up until March, 2012. Ten (71%) of 14 patients had an improvement in GVF areas (mean increase in retinal area of 28-683%). Six (43%) patients had an improvement in visual acuity (mean increase of 2-30 letters). Self-reported or parent-reported improvements in activities of daily living supported these findings. After 2 years, 11 (79%) patients had returned to their baseline GVF retinal area and ten (71%) had returned to baseline visual acuity letter values. Thus, three (21%) patients had a sustained GVF response and four (30%) had a sustained visual acuity response. Four patients had functional MRI scans, which correlated with visual response or absence of response to treatment. No serious adverse events occurred, although we noted transient headaches (11 patients), photophobia (11 patients), reduction in serum HDL concentrations (four patients), and increases in serum triglycerides (eight patients) and aspartate aminotransferase concentrations (two patients).
  
  
  CONCLUSIONS
  Non-invasive oral QLT091001 therapy is well tolerated, and can rapidly improve visual function in some patients with Leber congenital amaurosis and RPE65 and LRAT mutations.
  
  
  BACKGROUND
  QLT, Foundation Fighting Blindness Canada, CIHR, FRSQ, Reseau Vision.
authors.affiliation: McGill Ocular Genetics Laboratory and Paediatric Ophthalmology, Montreal Children's Hospital, Departments of Paediatric Surgery, Human Genetics and Ophthalmology, McGill University Health Centre, Montreal, Quebec, Canada. Electronic address: robert.koenekoop@mcgill.ca.
authors.forename: Robert K
authors.initials: RK
authors.lastname: Koenekoop
authors.affiliation: Ophthalmology, Peking Union Medical College Hospital, Beijing, China.
authors.forename: Ruifang
authors.initials: R
authors.lastname: Sui
authors.affiliation: Ophthalmology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Juliana
authors.initials: J
authors.lastname: Sallum
authors.affiliation: Medical Retina, Rotterdam Eye Hospital, Rotterdam, Netherlands.
authors.forename: L Ingeborgh
authors.initials: LI
authors.lastname: van den Born
authors.affiliation: McGill Ocular Genetics Laboratory and Paediatric Ophthalmology, Montreal Children's Hospital, Departments of Paediatric Surgery, Human Genetics and Ophthalmology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Radwan
authors.initials: R
authors.lastname: Ajlan
authors.affiliation: McGill Ocular Genetics Laboratory and Paediatric Ophthalmology, Montreal Children's Hospital, Departments of Paediatric Surgery, Human Genetics and Ophthalmology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Ayesha
authors.initials: A
authors.lastname: Khan
authors.affiliation: Department of Ophthalmology, Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands.
authors.forename: Anneke I
authors.initials: AI
authors.lastname: den Hollander
authors.affiliation: Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands.
authors.forename: Frans P M
authors.initials: FP
authors.lastname: Cremers
authors.affiliation: McGill Vision Research Unit and Department of Ophthalmology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Janine D
authors.initials: JD
authors.lastname: Mendola
authors.affiliation: The Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Ava K
authors.initials: AK
authors.lastname: Bittner
authors.affiliation: The Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Gislin
authors.initials: G
authors.lastname: Dagnelie
authors.affiliation: Neurosurgery, Stanford University, CA, USA.
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Schuchard
authors.affiliation: Vitreoretinal Associates of Washington, Seattle, WA, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Saperstein
mesh_terms: D000217:Acyltransferases / Q000172:deficiency / Q000235:genetics; D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D001766:Blindness / Q000188:drug therapy* / Q000235:genetics; D002648:Child; D004224:Diterpenes; D006801:Humans; D057130:Leber Congenital Amaurosis / Q000188:drug therapy* / Q000235:genetics; D009154:Mutation / Q000235:genetics; D011446:Prospective Studies; D000084562:Retinyl Esters; D014792:Visual Acuity / Q000187:drug effects; D014801:Vitamin A / Q000008:administration & dosage / Q000031:analogs & derivatives*; D055815:Young Adult; D019745:cis-trans-Isomerases / Q000172:deficiency / Q000235:genetics; D000099178:Retinoid Isomerohydrolase
chemical_list: D000217:Acyltransferases; D004224:Diterpenes; D000084562:Retinyl Esters; D014801:Vitamin A; D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase; C009166:retinol acetate; C056942:lecithin-retinol acyltransferase