Long-Term Follow-Up Gene Therapy Study for Achromatopsia CNGB3 and CNGA3
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ClinicalTrials.gov Identifier: NCT03278873 |
Recruitment Status :
Recruiting
First Posted : September 12, 2017
Last Update Posted : February 25, 2021
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Achromatopsia | Biological: either AAV - CNGB3 or AAV - CNGA3 | Phase 1 Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 72 participants |
Allocation: | Non-Randomized |
Intervention Model: | Single Group Assignment |
Intervention Model Description: | Follow-up of patients from two separate trials but there is no difference in follow-up assessments for the patients therefore they can be considered a "single group" |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | Long-term Follow-up Study of Participants Following an Open Label, Multi-centre, Phase I/II Dose Escalation Trial of a Recombinant Adeno-associated Virus Vector (AAV2/8-hCARp.hCNGB3 and AAV2/8-hG1.7p.coCNGA3) for Gene Therapy of Adults and Children With Achromatopsia Owing to Defects in CNGB3 or CNGA3 |
Actual Study Start Date : | June 27, 2017 |
Estimated Primary Completion Date : | July 10, 2024 |
Estimated Study Completion Date : | August 7, 2024 |

Arm | Intervention/treatment |
---|---|
Experimental: Biological-Low dose of either AAV - CNGB3 or AAV - CNGA3
Subretinal administration of a single low dose of either AAV - CNGB3 or AAV - CNGA3
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Biological: either AAV - CNGB3 or AAV - CNGA3
Comparison of different dosages of either AAV - CNGB3 or AAV - CNGA3 |
Experimental: Biological-medium dose of either AAV - CNGB3 or AAV - CNGA3
Subretinal administration of a single medium dose of either AAV - CNGB3 or AAV - CNGA3
|
Biological: either AAV - CNGB3 or AAV - CNGA3
Comparison of different dosages of either AAV - CNGB3 or AAV - CNGA3 |
Experimental: Biological-high dose of either AAV - CNGB3 or AAV - CNGA3
Subretinal administration of a single high dose of either AAV - CNGB3 or AAV - CNGA3
|
Biological: either AAV - CNGB3 or AAV - CNGA3
Comparison of different dosages of either AAV - CNGB3 or AAV - CNGA3 |
- Incidence of Adverse Events related to the treatment [ Time Frame: 5 Years ]longer term safety as the absence of ATIMP-related safety events
- Improvement in the visual function [ Time Frame: 5 years ]Improvements in visual function as assessed by visual assessment
- Improvement in retinal function [ Time Frame: 5 years ]Improvement in the retinal function as assessed by visual assessment
- Improvement in quality of life [ Time Frame: 5 years ]Quality of life will be measured by QoL questionnaires

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Ages Eligible for Study: | 3 Years to 100 Years (Child, Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion in the study will be limited to individuals who:
- Are able to give informed consent or assent, with or without the guidance of their parent(s)/guardian(s) where appropriate
- Received AAV2/8-hCARp.hCNGB3 or AAV2/8-hG1.7p.coCNGA3 by intraocular administration in the prior open-label, Phase I/II, dose escalation study (EudraCT 2016-002290-35 or EudraCT 2018-003431-29)
- Are willing to adhere to the protocol and long-term follow-up
Individuals will be excluded who:
Are unwilling or unable to meet with the requirements of the study

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03278873
Contact: MeiraGTx UK II Ltd | +44 (0)20 3866 4320 | ocularinfo@meiragtx.com |
United Kingdom | |
Moorfields Eye Hospital NHS Foundation Trust | Recruiting |
London, United Kingdom | |
Contact: Michel Michaelides michel.michaelides@ucl.ac.uk | |
Principal Investigator: James Bainbridge, Prof | |
Sub-Investigator: Michel Michaelides, Prof |
Responsible Party: | MeiraGTx UK II Ltd |
ClinicalTrials.gov Identifier: | NCT03278873 |
Other Study ID Numbers: |
MGT007 2016-003856-59 ( EudraCT Number ) |
First Posted: | September 12, 2017 Key Record Dates |
Last Update Posted: | February 25, 2021 |
Last Verified: | February 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Achromatopsia CNGB3 CNGA3 |
Color Vision Defects Vision Disorders Sensation Disorders Neurologic Manifestations |
Nervous System Diseases Cone Dystrophy Eye Diseases, Hereditary Eye Diseases |