Efficacy and Safety Study of Bilateral IVT Injection of GS010 at Two Dose Levels in LHON Patients

Exclusion Criteria

• •1\. Any known allergy or hypersensitivity to GS010 or any of its constituents 2. Contraindication to IVT in any eye according to the Investigator's clinical judgment and international guidelines (Avery, 2014) 3. Prior intraocular surgery or procedure or IVT, which occurred 6 months prior to inclusion and is considered of clinical relevance per Investigator assessment, or planned intraocular surgery or procedure 4. Presence of optic neuropathy from any cause except LHON, as determined by the Investigator 5. History of recurrent uveitis (idiopathic or immune-related) or active intraocular inflammation, as determined by the Investigator 6. Indication of a unilateral treatment with GS010, as determined by the Investigator:
• •* Unilateral or asymmetric ND4 LHON disease: only one eye affected with a vision loss due to ND4 LHON, and the fellow eye with preserved BCVA (LogMAR 0 or close to 0);
• •* Amblyopia: unilateral treatment of the functional eye with a vision loss due to ND4 LHON;
• •* Patient's desire for unilateral treatment 7. Ingestion of idebenone less than 7 days prior to the Inclusion visit (Day -1) 8. Inability to tolerate the anti-inflammatory regimen 9. Presence of ocular disease (excluding LHON), or systemic disease, or condition (including medications and laboratory test abnormalities) that could compromise patient safety or interfere with assessment of efficacy and safety, as determined by the Investigator 10. Use of any investigational drug, or device, within 90 days, or 5 half-lives, preceding the Inclusion visit (Day-1), whichever is longer, or plans to participate in another study of an investigational drug or device during the study period 11. Previous treatment with ocular gene therapy in either eye. 12. Pregnancy or breast-feeding