Natural History of Autosomal Dominant Optic Atrophy (ADOA), Caused by OPA1 Mutation

Inclusion Criteria: * Participants and/or their parent(s)/guardian(s) must have given written informed consent before any study-related activities are carried out and must be able to understand the full nature and purpose of the trial, including possible risks and adverse effects. Assent, where appropriate, will be obtained according to institutional guidelines. * Males and females, 8 years of age and above. * Have a clinical diagnosis of OPA1 mutation (haploinsufficiency) associated ADOA. * No other ocular pathology. * Patients with best-corrected visual acuity (BCVA) of between 20/40 (70 Early Treatment of Diabetic Retinopathy Study \[ETDRS\] letters) and 20/160 (39-43 ETDRS letters) * Willing and able to comply with all study assessments and adhere to the protocol schedule and restrictions. * For sites performing the Detection of apoptosis in retinal cells (DARC) procedure, and in volunteers ≥ 12 years only: 1. Female volunteers must: I. Be of non-child-bearing potential at least 6 weeks before the screening visit or postmenopausal (where postmenopausal is defined as no menses for 12 months without an alternative medical cause), or II. If of childbearing potential, must: * Have a negative pregnancy test at the screening visit and prior to each administration of ANX776, and * Agree not to attempt to become pregnant or donate ova from signing the consent form until at least 30 days after the last dose of ANX776, and * Agree to use adequate contraception (defined as the use of a condom by the male partner combined with the use of a highly effective method of contraception from one month prior to screening until at least 30 days after the last dose of ANX776, if not exclusively in a same-sex relationship or abstinent as a committed lifestyle. 2. Male volunteers must: * Agree not to donate sperm from signing the consent form until at least 90 days after the last dose of ANX776, and * If engaging in sexual intercourse with a female partner who could become pregnant, agree to use adequate contraception (defined as the use of a condom combined with the use of a highly effective method of contraception) from signing the consent form until at least 90 days after the last dose of study drug. Exclusion Criteria: * Participant has a known allergy to ANX776 or any of its excipients. * Have any uncontrolled systemic disease that, in the opinion of the Investigator, would preclude participation in the study, which includes but is not limited to, infection, uncontrolled elevated blood pressure, cardiovascular disease, or glycemic control issues, or any other medical condition that may put the participant at risk due to study procedures. Note: comorbidities relevant to the pathogenesis of OPA1 associated ADOA (including hearing loss, peripheral neuropathy, myopathy, and ataxia) are acceptable. * Have mutations in genes that cause ADOA, other than OPA1 (for example in case of dominant negative ADOA) and ADOA Plus. * Within 3 months prior to Baseline (Visit 2), have undergone any vitreoretinal surgery (scleral buckle, pars plana vitrectomy, retrieval of a dropped nucleus or intraocular lens, radial optic neurotomy, sheathotomy, cyclodestructive procedures or multiple filtration surgeries \[2 or more\]) or any other ocular surgery. * Have ocular media opacity or poor pupillary dilation prohibiting quality ophthalmic evaluation or photography, as assessed by the Investigator. * Have used any investigational drug or device within 90 days or 5 estimated half-lives of Visit 2, whichever is longer, or plan to participate in another study of a drug or device during the study period. Participation in observational trials is allowable based on Investigator discretion and consultation with the Medical Monitor. It is assumed that the observational trial evaluations would not interfere with participation in this study. * Have received any prior cell or gene therapy for a retinal condition. * Have a recent history (\<6 months) of or current excessive recreational drug or alcohol use, in the opinion of the Investigator. Note: excessive alcohol use is defined as regular consumption of \> 10 standard drinks per week or \> 4 standard drinks per day, where 1 standard drink is defined as 10 grams of pure alcohol. * Any other condition or prior therapy that in the opinion of the Investigator would make the volunteer unsuitable for this study, including inability to cooperate fully with the requirements of the study protocol or likelihood of noncompliance with any study requirements.