A Safety Study of Contralateral Eye Dosing of VGR-R01 in Participants With Bietti's Crystalline Dystrophy (BCD)

A Clinical Study Evaluating Subretinal Injection of VGR-R01 in the Contralateral Eye of Participants With Bietti's Crystalline Dystrophy Who Had Received VGR-R01 Administration

This is a multi-centre, single- arm, non-randomized, open-label phase 1/2 clinical trial which enables dosing of the fellow eyes of patients who received VGR-R01 administration in previous studies.

Study Overview

• Status: Not yet recruiting
• Conditions: Bietti Crystalline Dystrophy
• Intervention / Treatment: Biological: VGR-R01

Detailed Description

VGR-R01 is a novel Adeno-associated virus (AAV) vector carrying the human Cytochrome P450 Family 4 Subfamily V Member 2 (CYP4V2) coding sequence. This study will evaluate the safety and efficacy of VGR-R01 administered in the contralateral eye (the second treated eye) of subjects enrolled in the VGR-R01-001 and VGR-R01-101 studies, along with assessments of immunogenicity and vector shedding. Additionally, the long-term safety and efficacy of VGR-R01 treatment will be continuously assessed for up to 5 years after the last dose.

• Study Type: Interventional
• Enrollment (Estimated): 15
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Yan Jiang; Phone Number: 086-15802234907; Email: yan.jiang@vitalgen.com

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China
      • Beijing Tongren Hospital
      • Contact: Yan Jiang; Phone Number: 086-15802234907; Email: yan.jiang@vitalgen.com
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China
      • Shanghai General Hospital (Shanghai First People's Hospital)
      • Contact: Yan Jiang; Phone Number: 086-15802234907; Email: yan.jiang@vitalgen.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Key Inclusion Criteria:

1. Participants received VGR-R01 administration in the VGR-R01-001 or VGR-R01-101 studies.
2. Able to provide informed consent and comply with requirements of the study;
3. Hand Motion ≤ BCVA ≤ 75 ETDRS letters in the second treated eye.

Key Exclusion Criteria:

1. Have insufficient viable retinal photoreceptor cells based on investigator's decision;
2. Have current ocular or periocular infections, or endophthalmitis;
3. Have any significant ocular disease/disorder other than BCD, including age-related macular degeneration, diabetic retinopathy, optic neuropathy, significant lens opacity, glaucoma, uveitis, retinal detachment, etc;
4. Have intraocular surgery history except cataract surgery in the study eye;
5. Have or potentially require of systemic medications that may cause eye injure;
6. Have contraindications for corticosteroids or immunosuppressant;
7. Abnormal coagulation function or other clinically significant abnormal laboratory results;
8. Have malignancies or history of malignancies;
9. History of immunodeficiency (acquired or congenital); Other protocol defined Inclusion/Exclusion criteria may apply.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: VGR-R01 group; Single-dose Subretinal Administration of VGR-R01	Biological: VGR-R01; CYP4v2-coding gene delivered by AAV vector

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of adverse events and serious adverse events	Ocular/non-ocular adverse events are collected. The ophthalmic examination will include Best Corrected Visual Acuity (BCVA), Intraocular Pressure (IOP), slit lamp examination, angiography and Optical Coherence Tomography (OCT), etc. If any potential changes accompanied by clinical symptoms, or results in a change of medical intervention, the findings will be considered as clinically significant based on investigator's decision.	Up to Year 5
Number of participants with clinically significant change from baseline in vital signs, clinically laboratory abnormalities and ophthalmic examination findings	Vital signs (temperature, respiratory rate, pulse rate, systolic and diastolic blood pressure) will be obtained with participant in the seated position, after having sat calmly for at least 10 minutes. Laboratory Tests will include hematology, coagulation, blood chemistry, urinalysis, serology, and pregnancy test, etc. Ophthalmic Examination will include BCVA, IOP, slit lamp examination, angiography and OCT, etc. Clinical significance of the above signs will be determined at the investigator's discretion.	Up to Year 5

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline in BCVA	BCVA will be assessed with the Early Treatment of Diabetic Retinopathy Study (ETDRS) visual acuity (VA) chart..	Year 5
Change from baseline in multi-luminance mobility test (MLMT) score	Subjects will navigate a standardized mobility maze under set conditions as specified times during the study. All light-levels used for testing will be rounded to one of the following specified light levels: 0.1, 1, 4, 10, 50, 125, 250, or 400 lux. The corresponding scores for the above light levels range from 7 to 0, in descending order. -1 point means failing to pass the test at the 400 lux level; the lower the score, the worse the functional vision of the participant.	Year 5
Change from baseline in optical coherence tomography (OCT)	Change from baseline in central retinal thickness (CRT) as imaged by OCT.	Year 5
Number of subjects with the presence of immunogenicity	Assessed as presence of systemic cell-mediated or humoral responses to capsid or transgene product.	Year 5
Number of subjects with the presence of vector shedding	Assessed as the presence of vector in peripheral blood or collected tear.	Year 5
Fixation stability	Number of treated eyes with changes from baseline in fixation stability with MP-3 Microperimetry. Fixation stability is rated into three levels: stable fixation, relatively unstable fixation, and unstable fixation, with fixed standard reporting on the device settings.	Year 5
Light sensitivity	Changes from baseline in light sensitivity with MP-3 Microperimetry. The MP-3 has a stimulus intensity range of 0 to 34 decibels (dB).	Year 5

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual field index (VFI)	Assessed by Humphery static visual field testing. The VFI is a sophisticated index that range from 0% to 100%. It estimates the percentage of the visual field that the higher the better of visual function. Changes from baseline in VFI will be evaluated.	Year 5
Central threshold test	The central threshold test is a parameter in the Humphrey visual field test report, used to quantitatively assess the light sensitivity of the fovea (the area that provides the clearest central vision). It is a numerical value expressed in decibels (dB); the higher the value, the better the foveal light sensitivity.	Year 5
Change from baseline in NEI-VFQ-25 score	As assessed by the National Eye Institute Visual Function Questionnaire -25 (NEI-VFQ-25 questionnaire). NEI-VFQ-25 score ranges from 0 to 100, higher scores indicate better quality of life.	Year 5
Change from baseline in CLVQOL score	As assessed by the Chinese version of the Low Vision Quality-of-Life Questionnaire (CLVQOL questionnaire). CLVQOL score ranges from 0 to 125; higher scores indicate better quality of life.	Year 5

Collaborators and Investigators

• Sponsor: Shanghai Vitalgen BioPharma Co., Ltd.
• Investigators: Principal Investigator: Wenbin Wei, Beijing Tongren Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): July 31, 2027
• Study Completion (Estimated): July 31, 2031

Study Registration Dates

• First Submitted: April 23, 2026
• First Submitted That Met QC Criteria: May 12, 2026
• First Posted (Actual): May 14, 2026

Study Record Updates

• Last Update Posted (Actual): May 14, 2026
• Last Update Submitted That Met QC Criteria: May 12, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: gene therapy; VGR-R01; CYP4V2
• Additional Relevant MeSH Terms: Bietti Crystalline Dystrophy
• Other Study ID Numbers: VGR-R01-102

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