Open-Label Study to Evaluate the Safety, Tolerability, and Efficacy of Gene Therapy (SPVN20) in Subjects With Rod-Cone Dystrophy

Prior treatment

• Participant participating in another clinical trial and receiving an investigational medicinal product (IMP) within either 5 half-lives of that IMP, or 90 days prior to the injection of SPVN20.
• Participant who has received immunosuppressive therapies or any other therapy known to impact the immune system during the last month prior to SPVN20 administration.
• Participant who received any vaccination/immunization within 28 days prior to screening and/or during screening.
• Participant who previously received any gene therapy product, stem cell therapy, cell-based therapy for ocular or non-ocular disease.
• Participant with a retinal implant at enrollment.
• Participant who had intraocular surgery within 90 days of study treatment administration.
• Participant currently taking restricted classes of medications listed in protocol

Other illness

• Participant with cortical visual impairment.
• Participant with systemic disease or other pathology not related to their diagnosis of RCD, and whose symptoms or associated treatments may affect vision.
• Participant with known allergies to corticosteroids, or who will be unable to tolerate the corticosteroid regimen.
• Active ocular inflammation or recurrent history of idiopathic or autoimmune-associated uveitis.
• Participant known to be allergic to any of the delivery vehicle constituents or to any other drugs planned to be used during the clinical study.
• Participant positive for human immunodeficiency virus (HIV) or any other systemic immunocompromising disease.
• Participant with active Hepatitis B or Hepatitis C.
• Participant with clinically active ocular infection of herpetic diseases.
• Participant with active coronavirus disease (COVID-19) infection.
• Participant with pre-existing eye conditions that would interfere with the interpretation of study endpoints, or increase the risk of surgical complications.
• Participant with history of corticosteroid-induced raised IOP of \>25 mmHg following corticosteroid exposure, despite topical IOP-lowering pharmacologic therapy.
• Participant with history of unresolved rhegmatogenous retinal detachment in the fovea.
• Participant with history of unresolved ocular hypotony.
• Participant with any condition that would not allow them to complete follow-up examinations during the study and, in the opinion of the Investigator, would make them unsuitable for the study.
• Participant with ongoing cardiac or neurological disorders not managed by a restricted medication can be excluded based on the Investigator's judgement.

Other

• Active alcohol or substance abuse.
• Female participant currently pregnant or breastfeeding or intending to become pregnant.
• Participant with significant media opacity impacting evaluation of the retina or vitreous.
• Participant unwilling or unable (based on the Investigator's judgment) to comply with the study protocol.
• Women of childbearing potential (WOCBP) and men and/or their partner(s) of childbearing potential who do not agree to use a highly effective contraceptive method.

• Age ≥ 18 years old at enrollment.
• Participant with a genetically confirmed clinical diagnosis of advanced RCD in both eyes due to non-syndromic RCD.
• Participants enrolled in the Dose-Escalation cohorts must have a BCVA meeting the study eye criteria.
• Documented preservation of foveal cone cell bodies in the study eye (as shown on SD-OCT imaging).
• Participant with a history of formed vision.
• Participant willing and able to provide informed consent.