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Mohanty S, Batabyal S, Ayyagari A, Sharif NA. Safety of intravitreally delivered AAV2 vector-mediated multi-characteristic opsin genetic construct in wild type beagle dogs. J Gene Med 2024; 26:e3720. [PMID: 39041639 DOI: 10.1002/jgm.3720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 06/19/2024] [Accepted: 06/28/2024] [Indexed: 07/24/2024] Open
Abstract
BACKGROUND A novel adeno-associated virus 2 (AAV2)-carried multi-characteristic opsin (MCO) (MCO-010) is undergoing several clinical trials as a novel therapeutic modality for the treatment of degenerative retinal diseases including retinitis pigmentosa and Stargardt disease. The present study aimed to determine the ocular and systemic safety of MCO-010 and the AAV2 vehicle in adult Beagle dogs following intravitreal (IVT) injection. METHODS The current safety/toxicology studies spanning 13 weeks described here utilized well-documented techniques to assess the effects of IVT injection of MCO-010 up to 2.2 × 1011 genome copies (gc) per eye, or the AAV2 capsid (vehicle control) on gross behavioral and immunogenic changes, alterations in body weights, blood biochemistry, hematology, blood coagulation, gross necropsy lesions, organ weight changes and histopathology in the dogs (n = 4 per group; two males and two females per group). Immunohistochemical and functional electroretinogram studies were also conducted to determine MCO expression in the retina and determine any retinal toxicity associated with MCO-010. RESULTS There were no significant deleterious effects of the MCO-010 (or the AAV2 at the tested doses) on any of the examined parameters, including the absence of any severe ocular or systemic adverse events. However, as expected, inflammation after IVT delivery of AAV2 and MCO-010 was observed in the conjunctivae of all groups of animals, although this self-resolved within 1 week post-injection. Quantitative immunohistochemical analyses of MCO-010-associated mCherry revealed successful delivery of the gene therapy within the inner retina. CONCLUSIONS In summary, MCO-010 demonstrated a favorable safety profile when administered to the eyes of adult Beagle dogs of both sexes at dose levels up to 2.2 × 1011 gc per eye, with no adverse effects observed. This dose was identified as the No Observed Adverse Effect Level (i.e. NOAEL) and guided selection of safe doses for human clinical trials.
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Affiliation(s)
- Samarendra Mohanty
- Nanoscope Technologies LLC, Bedford, TX, USA
- Nanoscope Therapeutics Inc., Dallas, TX, USA
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Wu KY, Kulbay M, Toameh D, Xu AQ, Kalevar A, Tran SD. Retinitis Pigmentosa: Novel Therapeutic Targets and Drug Development. Pharmaceutics 2023; 15:685. [PMID: 36840007 PMCID: PMC9963330 DOI: 10.3390/pharmaceutics15020685] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 02/12/2023] [Accepted: 02/16/2023] [Indexed: 02/19/2023] Open
Abstract
Retinitis pigmentosa (RP) is a heterogeneous group of hereditary diseases characterized by progressive degeneration of retinal photoreceptors leading to progressive visual decline. It is the most common type of inherited retinal dystrophy and has a high burden on both patients and society. This condition causes gradual loss of vision, with its typical manifestations including nyctalopia, concentric visual field loss, and ultimately bilateral central vision loss. It is one of the leading causes of visual disability and blindness in people under 60 years old and affects over 1.5 million people worldwide. There is currently no curative treatment for people with RP, and only a small group of patients with confirmed RPE65 mutations are eligible to receive the only gene therapy on the market: voretigene neparvovec. The current therapeutic armamentarium is limited to retinoids, vitamin A supplements, protection from sunlight, visual aids, and medical and surgical interventions to treat ophthalmic comorbidities, which only aim to slow down the progression of the disease. Considering such a limited therapeutic landscape, there is an urgent need for developing new and individualized therapeutic modalities targeting retinal degeneration. Although the heterogeneity of gene mutations involved in RP makes its target treatment development difficult, recent fundamental studies showed promising progress in elucidation of the photoreceptor degeneration mechanism. The discovery of novel molecule therapeutics that can selectively target specific receptors or specific pathways will serve as a solid foundation for advanced drug development. This article is a review of recent progress in novel treatment of RP focusing on preclinical stage fundamental research on molecular targets, which will serve as a starting point for advanced drug development. We will review the alterations in the molecular pathways involved in the development of RP, mainly those regarding endoplasmic reticulum (ER) stress and apoptotic pathways, maintenance of the redox balance, and genomic stability. We will then discuss the therapeutic approaches under development, such as gene and cell therapy, as well as the recent literature identifying novel potential drug targets for RP.
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Affiliation(s)
- Kevin Y. Wu
- Division of Ophthalmology, Department of Surgery, University of Sherbrooke, Sherbrooke, QC J1G 2E8, Canada
| | - Merve Kulbay
- Faculty of Medicine, University of Montreal, Montreal, QC H3T 1J4, Canada
| | - Dana Toameh
- Faculty of Medicine, McGill University, Montreal, QC H3G 2M1, Canada
| | - An Qi Xu
- Faculty of Medicine, University of Montreal, Montreal, QC H3T 1J4, Canada
| | - Ananda Kalevar
- Division of Ophthalmology, Department of Surgery, University of Sherbrooke, Sherbrooke, QC J1G 2E8, Canada
| | - Simon D. Tran
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC H3A 1G1, Canada
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Optogenetic Therapy for Visual Restoration. Int J Mol Sci 2022; 23:ijms232315041. [PMID: 36499371 PMCID: PMC9735806 DOI: 10.3390/ijms232315041] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/29/2022] [Accepted: 11/29/2022] [Indexed: 12/02/2022] Open
Abstract
Optogenetics is a recent breakthrough in neuroscience, and one of the most promising applications is the treatment of retinal degenerative diseases. Multiple clinical trials are currently ongoing, less than a decade after the first attempt at visual restoration using optogenetics. Optogenetic therapy has great value in providing hope for visual restoration in late-stage retinal degeneration, regardless of the genotype. This alternative gene therapy consists of multiple elements including the choice of target retinal cells, optogenetic tools, and gene delivery systems. Currently, there are various options for each element, all of which have been developed as a product of technological success. In particular, the performance of optogenetic tools in terms of light and wavelength sensitivity have been improved by engineering microbial opsins and applying human opsins. To provide better post-treatment vision, the optimal choice of optogenetic tools and effective gene delivery to retinal cells is necessary. In this review, we provide an overview of the advancements in optogenetic therapy for visual restoration, focusing on available options for optogenetic tools and gene delivery methods.
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Rotov AY, Firsov ML. Optogenetic Prosthetization of Retinal Bipolar Cells. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022060011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Abstract
Although the experience of optogenetic retinal prosthetics
in animal models dates back to more than 16 years, the first results
obtained on humans have only been reported in the last year. Over this
period, the main challenges of prosthetics became clear and the
approaches to their solution were proposed. In this review, we aim
to present the achievements in the field of optogenetic prosthetization
of retinal bipolar cells with a focus mainly on relatively recent
publications. The review addresses the advantages and disadvantages
of bipolar cell prosthetics as compared to the alternative target,
retinal ganglion cells, and provides a comparative analysis of the
effectiveness of ionotropic light-sensitive proteins (channelrhodopsins)
or metabotropic receptors (rhodopsins) as prosthetic tools.
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Nikonov S, Aravand P, Lyubarsky A, Nikonov R, Luo AJ, Wei Z, Maguire AM, Phelps NT, Shpylchak I, Willett K, Aleman TS, Huckfeldt RM, Ramachandran PS, Bennett J. Restoration of Vision and Retinal Responses After Adeno-Associated Virus-Mediated Optogenetic Therapy in Blind Dogs. Transl Vis Sci Technol 2022; 11:24. [PMID: 35604672 PMCID: PMC9145127 DOI: 10.1167/tvst.11.5.24] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 11/17/2021] [Indexed: 12/02/2022] Open
Abstract
Purpose Optogenetic gene therapy to render remaining retinal cells light-sensitive in end-stage retinal degeneration is a promising strategy for treatment of individuals blind because of a variety of different inherited retinal degenerations. The clinical trials currently in progress focus on delivery of optogenetic genes to ganglion cells. Delivery of optogenetic molecules to cells in the outer neural retina is predicted to be even more advantageous because it harnesses more of the retinal circuitry. However, this approach has not yet been tested in large animal models. For this reason, we evaluated the safety and efficacy of optogenetic therapy targeting remaining diseased cone photoreceptors in the Rcd1 dog model of retinitis pigmentosa. Methods Imaging and measures of retinal function and functional vision were carried out, as well as terminal studies evaluating multi-electrode array recordings and histology. Results Animals remained healthy and active throughout the study and showed improved retinal and visual function as assessed by electroretinography and visual-evoked potentials, improved navigational vision, and improved function of cone photoreceptors and the downstream retinal circuitry. Conclusions The findings demonstrate that an optogenetic approach targeting the outer retina in a blind large animal model can partially restore vision. Translational Relevance This work has translational relevance because the approach could potentially be extrapolated to treat humans who are totally blind because of retinal degenerative disease.
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Affiliation(s)
- Sergei Nikonov
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Puya Aravand
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Arkady Lyubarsky
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Roman Nikonov
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Angela J. Luo
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Zhangyong Wei
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Albert M. Maguire
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Nicholas T. Phelps
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Ivan Shpylchak
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Keirnan Willett
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Tomas S. Aleman
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Rachel M. Huckfeldt
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Pavitra S. Ramachandran
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Jean Bennett
- Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology Scheie Eye Institute, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
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McClements ME, Staurenghi F, MacLaren RE, Cehajic-Kapetanovic J. Optogenetic Gene Therapy for the Degenerate Retina: Recent Advances. Front Neurosci 2020; 14:570909. [PMID: 33262683 PMCID: PMC7686539 DOI: 10.3389/fnins.2020.570909] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 10/23/2020] [Indexed: 12/18/2022] Open
Abstract
The degeneration of light-detecting rod and cone photoreceptors in the human retina leads to severe visual impairment and ultimately legal blindness in millions of people worldwide. Multiple therapeutic options at different stages of degeneration are being explored but the majority of ongoing clinical trials involve adeno-associated viral (AAV) vector-based gene supplementation strategies for select forms of inherited retinal disease. Over 300 genes are associated with inherited retinal degenerations and only a small proportion of these will be suitable for gene replacement therapy. However, while the origins of disease may vary, there are considerable similarities in the physiological changes that occur in the retina. When early therapeutic intervention is not possible and patients suffer loss of photoreceptor cells but maintain remaining layers of cells in the neural retina, there is an opportunity for a universal gene therapy approach that can be applied regardless of the genetic origin of disease. Optogenetic therapy offers such a strategy by aiming to restore vision though the provision of light-sensitive molecules to surviving cell types of the retina that enable light perception through the residual neurons. Here we review the recent progress in attempts to restore visual function to the degenerate retina using optogenetic therapy. We focus on multiple pre-clinical models used in optogenetic strategies, discuss their strengths and limitations, and highlight considerations including vector and transgene designs that have advanced the field into two ongoing clinical trials.
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Affiliation(s)
- Michelle E. McClements
- Nuffield Laboratory Ophthalmology, Department of Clinical Neurosciences, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - Federica Staurenghi
- Nuffield Laboratory Ophthalmology, Department of Clinical Neurosciences, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - Robert E. MacLaren
- Nuffield Laboratory Ophthalmology, Department of Clinical Neurosciences, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Jasmina Cehajic-Kapetanovic
- Nuffield Laboratory Ophthalmology, Department of Clinical Neurosciences, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
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Bucher K, Rodríguez-Bocanegra E, Dauletbekov D, Fischer MD. Immune responses to retinal gene therapy using adeno-associated viral vectors - Implications for treatment success and safety. Prog Retin Eye Res 2020; 83:100915. [PMID: 33069860 DOI: 10.1016/j.preteyeres.2020.100915] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/08/2020] [Accepted: 10/10/2020] [Indexed: 02/06/2023]
Abstract
Recombinant adeno-associated virus (AAV) is the leading vector for gene therapy in the retina. As non-pathogenic, non-integrating, replication deficient vector, the recombinant virus efficiently transduces all key retinal cell populations. Successful testing of AAV vectors in clinical trials of inherited retinal diseases led to the recent approval of voretigene neparvovec (Luxturna) for the treatment of RPE65 mutation-associated retinal dystrophies. However, studies applying AAV-mediated retinal gene therapy independently reported intraocular inflammation and/or loss of efficacy after initial functional improvements. Both observations might be explained by targeted removal of transduced cells via anti-viral defence mechanisms. AAV has been shown to activate innate pattern recognition receptors (PRRs) such as toll-like receptor (TLR)-2 and TLR-9 resulting in the release of inflammatory cytokines and type I interferons. The vector can also induce capsid-specific and transgene-specific T cell responses and neutralizing anti-AAV antibodies which both limit the therapeutic effect. However, the target organ of retinal gene therapy, the eye, is known as an immune-privileged site. It is characterized by suppression of inflammation and promotion of immune tolerance which might prevent AAV-induced immune responses. This review evaluates AAV-related immune responses, toxicity and inflammation in studies of retinal gene therapy, identifies influencing variables of these responses and discusses potential strategies to modulate immune reactions to AAV vectors to increase the safety and efficacy of ocular gene therapy.
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Affiliation(s)
- Kirsten Bucher
- University Eye Hospital, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany; Institute for Ophthalmic Research, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany
| | - Eduardo Rodríguez-Bocanegra
- University Eye Hospital, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany; Institute for Ophthalmic Research, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany
| | - Daniyar Dauletbekov
- University Eye Hospital, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany; Institute for Ophthalmic Research, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany
| | - M Dominik Fischer
- University Eye Hospital, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany; Institute for Ophthalmic Research, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany; Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK; Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
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8
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MacLaren RE. A 2020 vision of ocular gene therapy. Gene Ther 2020; 28:217-219. [PMID: 32601358 DOI: 10.1038/s41434-020-0170-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/04/2020] [Accepted: 06/23/2020] [Indexed: 11/09/2022]
Affiliation(s)
- Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford and Oxford University Hospitals NHS Foundation Trust NIHR Biomedical Research Centre, West Wing John Radcliffe Hospital, Oxford, OX3 9DU, UK.
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Richter C, Bruegmann T. No light without the dark: Perspectives and hindrances for translation of cardiac optogenetics. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 154:39-50. [PMID: 31515056 DOI: 10.1016/j.pbiomolbio.2019.08.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/18/2019] [Accepted: 08/27/2019] [Indexed: 12/30/2022]
Abstract
Over the last decade, optogenetic stimulation of the heart and its translational potential for rhythm control attracted more and more interest. Optogenetics allows to stimulate cardiomyocytes expressing the light-gated cation channel Channelrhodopsin 2 (ChR2) with light and thus high spatio-temporal precision. Therefore this new approach can overcome the technical limitations of electrical stimulation. In regard of translational approaches, the prospect of pain-free stimulation, if ChR2 expression is restricted to cardiomyocytes, is especially intriguing and could be highly beneficial for cardioversion and defibrillation. However, there is no light without shadow and cardiac optogenetics has to surmount critical hurdles, namely "how" to inscribe light-sensitivity by expressing ChR2 in a native heart and how to avoid side effects such as possible immune responses against the gene transfer. Furthermore, implantable light devices have to be developed which ensure sufficient illumination in a highly contractile environment. Therefore this article reviews recent advantages in the field of cardiac optogenetics with a special focus on the hindrances for the potential translation of this new approach into clinics and provides an outlook how these have to be carefully investigated and could be solved step by step.
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Affiliation(s)
- Claudia Richter
- RG Biomedical Physics, Max Planck Institute for Dynamics & Self-Organization, Am Fassberg 17, 37077, Goettingen, Germany; Department of Cardiology and Pneumology, University Medical Center, Robert-Koch-Str. 42a, 37075, Goettingen, Germany; DZHK e.V. (German Center for Cardiovascular Research), Partner Site Goettingen, 37075, Goettingen, Germany.
| | - Tobias Bruegmann
- DZHK e.V. (German Center for Cardiovascular Research), Partner Site Goettingen, 37075, Goettingen, Germany; Institute for Cardiovascular Physiology, University Medical Center Goettingen, Humboldtallee 23, 37073, Goettingen, Germany.
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Simunovic MP, Shen W, Lin JY, Protti DA, Lisowski L, Gillies MC. Optogenetic approaches to vision restoration. Exp Eye Res 2018; 178:15-26. [PMID: 30218651 DOI: 10.1016/j.exer.2018.09.003] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 08/16/2018] [Accepted: 09/07/2018] [Indexed: 10/28/2022]
Abstract
Inherited retinal disease (IRD) affects about 1 in 3000 to 1 in 5000 individuals and is now believed to be the most common cause of blindness registration in developed countries. Until recently, the management of such conditions had been exclusively supportive. However, advances in molecular biology and medical engineering have now seen the rise of a variety of approaches to restore vision in patients with IRDs. Optogenetic approaches are primarily aimed at rendering secondary and tertiary neurons of the retina light-sensitive in order to replace degenerate or dysfunctional photoreceptors. Such approaches are attractive because they provide a "causative gene-independent" strategy, which may prove suitable for a variety of patients with IRD. We discuss theoretical and practical considerations in the selection of optogenetic molecules, vectors, surgical approaches and review previous trials of optogenetics for vision restoration. Optogenetic approaches to vision restoration have yielded promising results in pre-clinical trials and a phase I/II clinical trial is currently underway (ClinicalTrials.gov NCT02556736). Despite the significant inroads made in recent years, the ideal optogenetic molecule, vector and surgical approach have yet to be established.
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Affiliation(s)
- M P Simunovic
- Save Sight Institute, University of Sydney, 8 Macquarie St., Sydney, NSW, 2000, Australia; Retinal Unit, Sydney Eye Hospital, 8 Macquarie St., Sydney, NSW, 2000, Australia.
| | - W Shen
- Retinal Unit, Sydney Eye Hospital, 8 Macquarie St., Sydney, NSW, 2000, Australia
| | - J Y Lin
- Faculty of Health, University of Tasmania, Private Bag 23, Hobart, TAS, 7000, Australia
| | - D A Protti
- Discipline of Physiology, University of Sydney, NSW, 2006, Australia
| | - L Lisowski
- Children's Medical Research Institute, University of Sydney, NSW, 2006, Australia; Military Institute of Hygiene and Epidemiology, 24-100, Puławy, Poland
| | - M C Gillies
- Save Sight Institute, University of Sydney, 8 Macquarie St., Sydney, NSW, 2000, Australia; Retinal Unit, Sydney Eye Hospital, 8 Macquarie St., Sydney, NSW, 2000, Australia
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