Oral Metformin for Treatment of ABCA4 Retinopathy
National Eye Institute (NEI)
Summary
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....
Description
Study Description: ABCA4 retinopathy is an autosomal recessive progressive retinal dystrophy that leads to retinal pigment epithelium (RPE) and photoreceptor degeneration, with consequent central visual loss. A treatment that either reduces the rate of lipofuscin accumulation or improves the clearance of lipofuscin in the RPE could potentially slow the degeneration associated with this disease. Metformin hydrochloride is a well-characterized, commonly prescribed oral anti-diabetic medication that acts by suppressing liver gluconeogenesis and increasing peripheral insulin sensitivity. An addi…
Eligibility
- Age range
- 12–100 years
- Sex
- All
- Healthy volunteers
- No
* INCLUSION CRITERIA: To be eligible, the following inclusion criteria must be met, where applicable. 1. Participant must be at least 12 years of age. 2. Participant (or legal guardian) must understand and sign the protocol s informed consent document. 3. Participant must have at least one definite pathogenic or likely pathogenic mutation in ABCA4 and a typical clinical presentation of Stargardt disease and phenotypic presentation of ABCA4 retinopathy in both eyes. 4. Participant must have at least two years of natural history data from at least four data points (a) The separation between an…
Interventions
- DrugMetformin hydrochloride
Metformin is commercially produced in immediate and extended release. Participants will receive an immediate release formulation of metformin of 500mg daily at study entry. This dose will be titrated up weekly in 500mg increments to reach a goal of 2000mg daily maximum. Once participants \>=17 years of age reach 2000mg metformin immediate release they will switch to an extended-release formulation (1000mg twice a day by mouth). Participants \>= 17 years of age that cannot tolerate 2000mg will be permitted to reduce their daily dose to a minimum of 1000mg/day. Because metformin extended release is not FDA-approved for children under the age of 17, participants under 17 will remain on the immediate release formulation. For these participants who remain on standard formulation, the maximum tolerated dose between 1000mg and 2000mg/day will be given.
Locations (2)
- National Institutes of Health Clinical CenterBethesda, Maryland
- University of MichiganAnn Arbor, Michigan