The Dark-Adapted Retinal Function Response in Choroideremia (DARC) Study

NCT ID: NCT05045703

Last Updated: 2023-06-29

Basic Information

• Recruitment Status: WITHDRAWN
• Clinical Phase: NA
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-05-31
• Study Completion Date: 2024-05-31

Brief Summary

Choroideremia (CHM) is an inherited retinal disorder that causes progressive vision loss, ultimately leading to complete blindness. The first symptom is generally night blindness, although, to date, little is known about the extent, type, pattern, and progression of dark-adapted visual function measures in CHM patients. We hypothesize that one of the key events causing night blindness in CHM is deficiency in the chromophore of the rod visual pigment, rhodopsin. We propose that this deficiency is at least in part due to inadequate delivery of vitamin A (all-trans-retinol) to the photoreceptors (PRs) from the ailing retinal pigment epithelium (RPE), characteristic of CHM. We hypothesize that increased availability of vitamin A would potentiate its entry into the RPE-mediated visual cycle, ultimately enabling delivery to the PRs. This would in turn allow rods to perform better by partially overcoming the RPE damage and the impaired chromophore recycling that we postulate exists in CHM. The goals of this proposal are: (1) to test the hypothesis that oral vitamin A supplementation can improve night time and peripheral vision in CHM patients, and (2) to provide detailed characterization of dark-adapted visual function outcome measures to guide interventional CHM trials.

Conditions

Choroideremia

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Vitamin A palmitate

Vitamin A palmitate, 15,000 IU daily for 4 months

Group Type: EXPERIMENTAL

Vitamin A palmitate

Intervention Type: DIETARY_SUPPLEMENT

Vitamin A palmitate, 15,000 IU daily for 4 months

Interventions

Vitamin A palmitate

Vitamin A palmitate, 15,000 IU daily for 4 months

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• males at least 15 years of age with molecularly-confirmed diagnosis of choroideremia

Exclusion Criteria

• inability to participate in visual field testing reliably and reproducibly

• Minimum Eligible Age: 15 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

Foundation Fighting Blindness

OTHER

Sponsor Role: collaborator

Duke University

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Duke Eye Center

Durham, North Carolina, United States

Countries

United States

Other Identifiers

Pro00108901

Identifier Type: -

Identifier Source: org_study_id