This is a phase 3 study to evaluate the efficacy and safety of VGR-R01 in subjects with Bietti Crystalline Dystrophy.

This is a multicenter, randomized controlled study which will enroll 45 subjects.

VGR-R01 is a novel AAV vector carrying the human CYP4v2 coding sequence. This study is intended to assess the efficacy of VGR-R01 in subjects with Bietti crystalline dystrophy (BCD) based on the change from baseline in best corrected visual acuity (BCVA) of the study eyes.

30 subjects will be enrolled in the intervention group and will receive monocular administration of VGR-R01, and 15 subjects in the control group will not receive any intervention. After completion of the trial, the untreated eyes will receive administration of VGR-R01 in subsequent clinical trial.

Key Inclusion Criteria:

1. Able to provide informed consent and comply with requirements of the study;
2. ≥18 years and <70 years of age;
3. Confirmed diagnosis of Bietti Crystalline Dystrophy and molecular diagnosis of CYP4V2 mutations (homozygotes or compound heterozygotes);
4. Hand Motion ≤ BCVA ≤ 60 ETDRS letters in the study 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. Unwilling or unable to have the planned follow-up;
8. Abnormal coagulation function or other clinically significant abnormal laboratory results;
9. Have malignancies or history of malignancies;
10. History of immunodeficiency (acquired or congenital); Other protocol defined Inclusion/Exclusion criteria may apply.

IPD will be shared with other researchers when VGR-R01 is fully approved