Optic Nerve Atrophy Clinical Trials

• Aged 15 years or older at the time of vision loss onset

• Clinically manifested vision loss due to ND4 LHON in both eyes

• BCVA of at least LogMAR +2.39, measured at the FrACT scale, in both eyes

• Documented results of genotyping showing the presence of pathogenic LHON-associated mutation(s) in the ND4 mitochondrial gene and the absence of other pathogenic LHON-associated mutations in the patient's mitochondrial DNA; absence of pathogenic mutations, other than the ND4 LHON-causing mutation(s), which are known to cause pathology of the optic nerve, retina or afferent visual system. Historic results of genetic analysis are acceptable upon Sponsor approval.

• Vision loss duration from 6 months to 1.5 years in the first affected eye at the Inclusion visit (Day 1)

• No limitations to OCT image collection that would prevent high quality, reliable images from being obtained in both eyes, as determined by the reading center

• Clear ocular media and adequate pupillary dilation to permit thorough ocular examination, as assessed by the Investigator

• Human immunodeficiency virus (HIV) negative serology

• Female patients of childbearing potential must agree to use effective methods of birth control for up to 6 months after Treatment visit (Day 0). Male patients must agree to use condoms with their female partners for up to 6 months after Treatment visit (Day 0).

⁃ Willing and able to comply with the protocol, follow study instructions, attend study visits as required and complete all study assessments

⁃ Patient - and parent/legal guardian if the patient is under 18 years of age - has provided signed, written informed consent