1
|
Jolly JK, Bridge H, MacLaren RE. Outcome Measures Used in Ocular Gene Therapy Trials: A Scoping Review of Current Practice. Front Pharmacol 2019; 10:1076. [PMID: 31620003 PMCID: PMC6759794 DOI: 10.3389/fphar.2019.01076] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Accepted: 08/23/2019] [Indexed: 12/14/2022] Open
Abstract
Multiple gene therapy trials are occurring for a variety of ophthalmic diseases around the world. The safety of gene therapy in the eye has been established, and the next step is to reliably assess efficacy. This is primarily done through the use of imaging techniques and visual function measures. Standardized visual function assessments, however, were originally developed for a clinical setting and may not be suitable for detecting and quantifying therapeutic changes. This scoping review takes a comprehensive look at current practice in terms of the outcome measures defined at trial registration. These were compared to the outcome measures reported in the literature. All published trials reported the pre-registered primary outcome measure. A range of additional secondary outcomes were reported that were not originally planned. Gaps in gene therapy assessment exist and further discussion are required to find a way forward, particularly as more conditions progress to phase 2 and 3 trials. Several factors impacting on trial design and outcome measure choice are discussed.
Collapse
Affiliation(s)
- Jasleen K Jolly
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Wellcome Integrative Neuroimaging Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Holly Bridge
- Wellcome Integrative Neuroimaging Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| |
Collapse
|
2
|
Nishiguchi KM, Fujita K, Tokashiki N, Komamura H, Takemoto-Kimura S, Okuno H, Bito H, Nakazawa T. Retained Plasticity and Substantial Recovery of Rod-Mediated Visual Acuity at the Visual Cortex in Blind Adult Mice with Retinal Dystrophy. Mol Ther 2018; 26:2397-2406. [PMID: 30064895 DOI: 10.1016/j.ymthe.2018.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 07/08/2018] [Accepted: 07/12/2018] [Indexed: 12/01/2022] Open
Abstract
In patients born blind with retinal dystrophies, understanding the critical periods of cortical plasticity is important for successful visual restoration. In this study, we sought to model childhood blindness and investigate the plasticity of visual pathways. To this end, we generated double-mutant (Pde6ccpfl1/cpfl1Gnat1IRD2/IRD2) mice with absent rod and cone photoreceptor function, and we evaluated their response for restoring rod (GNAT1) function through gene therapy. Despite the limited effectiveness of gene therapy in restoring visual acuity in patients with retinal dystrophy, visual acuity was, unexpectedly, successfully restored in the mice at the level of the primary visual cortex in this study. This success in visual restoration, defined by changes in the quantified optokinetic response and pattern visually evoked potential, was achieved regardless of the age at treatment (up to 16 months). In the contralateral visual cortex, cortical plasticity, tagged with light-triggered transcription of Arc, was also restored after the treatment in blind mice carrying an Arc promoter-driven reporter gene, dVenus. Our results demonstrate the remarkable plasticity of visual circuits for one of the two photoreceptor mechanisms in older as well as younger mice with congenital blindness due to retinal dystrophies.
Collapse
Affiliation(s)
- Koji M Nishiguchi
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan; Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan.
| | - Kosuke Fujita
- Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Naoyuki Tokashiki
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Hiroshi Komamura
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Sayaka Takemoto-Kimura
- Department of Neuroscience I, Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan; PRESTO-Japan Science and Technology Agency, Chiyoda-ku, Tokyo, Japan
| | - Hiroyuki Okuno
- Medical Innovation Center, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Haruhiko Bito
- Department of Neurochemistry, Graduate School of Medicine, University of Tokyo, Tokyo 113-0033, Japan
| | - Toru Nakazawa
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan; Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan; Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| |
Collapse
|
3
|
Hartman RR, Kompella UB. Intravitreal, Subretinal, and Suprachoroidal Injections: Evolution of Microneedles for Drug Delivery. J Ocul Pharmacol Ther 2017; 34:141-153. [PMID: 29206556 PMCID: PMC5963636 DOI: 10.1089/jop.2017.0121] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 10/13/2017] [Indexed: 01/04/2023] Open
Abstract
Even though the very thought of an injection into the eye may be frightening, an estimated 6 million intravitreal (IVT) injections were made in the USA during 2016. With the introduction of new therapeutic agents, this number is expected to increase. In addition, drug products that are injectable in ocular compartments other than the vitreous humor are expected to enter the back of the eye market in the not so distant future. Besides the IVT route, some of the most actively investigated routes of invasive administration to the eye include periocular, subretinal, and suprachoroidal (SC) routes. While clinical efficacy is the driving force behind new injectable drug product development for the eye, safety is also being improved with time. In the case of IVT injections, the procedural guidelines have evolved over the years to improve patient comfort and reduce injection-related injury and infection. Similar advances are anticipated for other routes of administration of injectable products to the eye. In addition to procedural improvements, the design of needles, particularly those with smaller diameters, length, and controlled bevel angles are expected to improve overall safety and acceptance of injected ophthalmic drug products. A key development in this area is the introduction of microneedles of a length less than a millimeter that can target the SC space. In the future, needles with smaller diameters and lengths, potentially approaching nanodimensions, are expected to revolutionize ophthalmic disease management.
Collapse
Affiliation(s)
- Rachel R. Hartman
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Uday B. Kompella
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado
- Department of Ophthalmology, University of Colorado Anschutz Medical Campus, Aurora, Colorado
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| |
Collapse
|
4
|
Gupta PR, Huckfeldt RM. Gene therapy for inherited retinal degenerations: initial successes and future challenges. J Neural Eng 2017; 14:051002. [DOI: 10.1088/1741-2552/aa7a27] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|