Long-Term Follow-Up Gene Therapy Study for Achromatopsia CNGB3 and CNGA3

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

This study is a longer-term follow-up study for patients who participated in one of the clinical trials: AAV - CNGB3 retinal gene therapy for patients with achromatopsia, or AAV - CNGA3 retinal gene therapy for patients with achromatopsia.

Study Overview

• Status: Active, not recruiting
• Conditions: Achromatopsia
• Intervention / Treatment: Biological: either AAV - CNGB3 or AAV - CNGA3

Detailed Description

The follow up study is designed to collect data on longer-term safety and efficacy.

• Study Type: Interventional
• Enrollment (Actual): 34
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• United Kingdom
  • London, United Kingdom
    • Moorfields Eye Hospital NHS Foundation Trust
• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48105
      • Kellog Eye Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 100 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion in the study will be limited to individuals who:

1. Are able to give informed consent or assent, with or without the guidance of their parent(s)/guardian(s) where appropriate
2. 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)
3. 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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / 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	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

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Adverse Events related to the treatment	longer term safety as the absence of ATIMP-related safety events	5 Years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Improvement in the visual function	Improvements in visual function as assessed by visual assessment	5 years
Improvement in retinal function	Improvement in the retinal function as assessed by visual assessment	5 years
Improvement in quality of life	Quality of life will be measured by QoL questionnaires	5 years

Collaborators and Investigators

• Sponsor: MeiraGTx UK II Ltd
• Collaborators: Syne Qua Non Limited; EMAS Pharma

Study record dates

Study Major Dates

• Study Start (Actual): June 29, 2017
• Primary Completion (Estimated): January 15, 2026
• Study Completion (Estimated): January 15, 2026

Study Registration Dates

• First Submitted: August 16, 2017
• First Submitted That Met QC Criteria: September 7, 2017
• First Posted (Actual): September 12, 2017

Study Record Updates

• Last Update Posted (Actual): March 15, 2024
• Last Update Submitted That Met QC Criteria: March 13, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Keywords: Achromatopsia; CNGB3; CNGA3
• Additional Relevant MeSH Terms: Nervous System Diseases; Eye Diseases; Neurologic Manifestations; Eye Diseases, Hereditary; Sensation Disorders; Vision Disorders; Cone Dystrophy; Color Vision Defects
• Other Study ID Numbers: MGT007; 2016-003856-59 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No