Oral Metformin for Treatment of ABCA4 Retinopathy

Background: ABCA4 retinopathy is a genetic disease in which the ABCA4 protein is absent or faulty. It can cause waste material to collect in the eye and may cause cells to die. The cell death can lead to vision loss. Researchers want to see if an oral drug called metformin can help. Objective: To see if metformin is safe and possibly helps to slow the rate of ABCA4 retinopathy. Eligibility: People age 12 and older who have ABCA4 retinopathy and have problems with their vision. Design: Participants will be screened under a separate protocol. Participants will have a medical and family history. They will complete a questionnaire about their vision and daily activities. They will have a physical exam. They may have blood drawn through a needle in the arm. Participants will have an eye exam. Their pupils may be dilated with eye drops. Their retina may be photographed. Participants will have a visual field test. They will sit in front of a large dome and press a button when they see a light within the dome. Participants will have an electroretinogram. It examines the function of the retina. They will sit in the dark for 30 minutes. Then their eyes will be numbed with eye drops. They will wear contact lenses that can sense signals from the retinas. They will watch flashing lights. Participants will have optical coherence tomography. This non-invasive procedure makes pictures of the retina. Participants will have fundus autofluorescence. A bright blue light will be shone into their eye. Participants will take metformin by mouth for 24 months. Participants will have study visits every 6 months. Participation will last for at least 36 months....

NCT Number	NCT04545736
Lead Sponsor	National Eye Institute (NEI)
Conditions	ABCA4 Retinopathy, Stargardt Disease, Retinal Dystrophy, Retinal Degeneration
Enrollment	55 participants
Start Date	2020-11-23
Primary Completion	2028-02-02 (estimated)
Study Completion	2029-02-02 (estimated)
Updated on ClinicalTrials.gov	2026-08-10