Study of Efficacy and Safety of Voretigene Neparvovec in Japanese Patients With Biallelic RPE65 Mutation-associated Retinal Dystrophy

This is an open-label, single-arm study to evaluate the safety and efficacy of bilateral subretinal administration of voretigene neparvovec in Japanese patients with biallelic RPE65 mutation-associated retinal dystrophy. Assessments will include full-field light sensitivity threshold testing, visual fields, visual acuity, vector shedding, immunogenicity and adverse events. Participants will be monitored for 5 years after treatment.

Inclusion criteria

• Japanese participants with biallelic RPE65 mutation-associated retinal dystrophy; molecular diagnosis of RPE65 mutation must be confirmed by a Novartis designated laboratory in Japan.
• Age four years or older.
• Visual acuity worse than 20/60 (both eyes) and/or visual field less than 20 degrees in any meridian as measured by a III4e isopter or equivalent (both eyes).
• Sufficient viable retinal cells as determined by non-invasive means, such as optical coherence tomography (OCT) and/ or ophthalmoscopy. Must have either:

• An area of retina within the posterior pole of > 100 µm thickness shown on OCT, or
• ≥ 3 disc areas of retina without atrophy or pigmentary degeneration within the posterior pole, or
• Remaining visual field within 30 degrees of fixation as measured by a III4e isopter or equivalent

Exclusion criteria

• Any prior participation in a study in which a gene therapy vector was administered.
• Participation in a clinical study with an investigational drug in the past 6 months from screening visit.
• Known hypersensitivity to any of the study treatments including excipients or to medications planned for use in the peri-operative period.
• Unable to reliably perform the FST assessment.
• Use of retinoid compounds or precursors that could potentially interact with the biochemical activity of the RPE65 enzyme in the past 6 months from screening visit.
• Prior intraocular surgery within 6 months from screening visit.
• Prior use of any medicines that, in the opinion of the investigator, may have caused retinal damage (e.g., sildenafil or related compounds, hydroxychloroquine, chloroquine, thioridazine, any other retino-toxic compounds)
• Pre-existing eye conditions or complicating systemic diseases that would preclude the planned surgery or interfere with the interpretation of study. Complicating systemic diseases would include those in which the disease itself, or the treatment for the disease, can alter ocular function.