search
Back to results

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

Primary Purpose

Choroideremia

Status
Withdrawn
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Vitamin A palmitate
Sponsored by
Duke University
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Choroideremia focused on measuring vitamin A, night vision

Eligibility Criteria

15 Years - undefined (Child, Adult, Older Adult)MaleAccepts Healthy Volunteers

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

Sites / Locations

  • Duke Eye Center

Arms of the Study

Arm 1

Arm Type

Experimental

Arm Label

Vitamin A palmitate

Arm Description

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

Outcomes

Primary Outcome Measures

Change in dark-adapted full-field visual field sensitivity
Dark-adapted full-field visual field sensitivity will be measured using the Medmont dark-adapted chromatic perimeter.
Change in dark-adapted macular visual field sensitivity
Dark-adapted macular visual field sensitivity will be measured using the Medmont dark-adapted chromatic perimeter.
Change in dark adaptometry
Dark adaptometry will be measured using the MacuLogix AdaptDx dark adaptometer.

Secondary Outcome Measures

Change in best corrected visual acuity
Best corrected visual acuity will be measured using the ETDRS chart
Change in low luminance visual acuity
Low luminance visual acuity will be measured using the ETDRS chart in low luminance conditions
Change in full-field light-adapted visual field sensitivity
Light-adapted full-field visual field sensitivity will be measured using the Octopus 172-point GATE full-field semi-automated kinetic perimetry (SKP)
Change in light-adapted macular visual field sensitivity
Light-adapted macular visual field sensitivity will be measured using the Centervue MAIA confocal macular microperimeter
Change in retinal pigmented epithelium (RPE) atrophy by optical coherence tomography
Retinal pigmented epithelium (RPE) atrophy will be measured using the Spectralis macular spectral domain optical coherence tomography (SD-OCT) with and without enhanced depth imaging (EDI)
Change in retinal pigmented epithelium (RPE) atrophy by color photography
Retinal pigmented epithelium (RPE) atrophy will be measured using the Optos wide-field color fundus photography (WF-CFP)
Change in retinal pigmented epithelium (RPE) atrophy by fundus autofluorescence
Retinal pigmented epithelium (RPE) atrophy will be measured using the Optos wide-field fundus auto-fluorescence (WF-FAF)
Change in retinal pigmented epithelium (RPE) atrophy by fundoscopy
Retinal pigmented epithelium (RPE) atrophy will be assessed by slit lamp biomicroscopy
Change in liver function
Liver function profile will be measured by laboratory using participant serum samples
Change in serum vitamin A levels
Serum vitamin A levels will be measured by laboratory using participant serum samples

Full Information

First Posted
September 7, 2021
Last Updated
June 27, 2023
Sponsor
Duke University
Collaborators
Foundation Fighting Blindness
search

1. Study Identification

Unique Protocol Identification Number
NCT05045703
Brief Title
The Dark-Adapted Retinal Function Response in Choroideremia (DARC) Study
Acronym
DARC
Official Title
Characterization of Night Vision Impairment in Choroideremia and Short-Term Vitamin A Supplementation: The Dark-Adapted Retinal Function Response in Choroideremia (DARC) Study
Study Type
Interventional

2. Study Status

Record Verification Date
June 2023
Overall Recruitment Status
Withdrawn
Why Stopped
PI left the institution
Study Start Date
May 2023 (Anticipated)
Primary Completion Date
March 2024 (Anticipated)
Study Completion Date
May 2024 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Duke University
Collaborators
Foundation Fighting Blindness

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
No

5. Study Description

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.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Choroideremia
Keywords
vitamin A, night vision

7. Study Design

Primary Purpose
Treatment
Study Phase
Not Applicable
Interventional Study Model
Single Group Assignment
Masking
None (Open Label)
Allocation
N/A
Enrollment
0 (Actual)

8. Arms, Groups, and Interventions

Arm Title
Vitamin A palmitate
Arm Type
Experimental
Arm Description
Vitamin A palmitate, 15,000 IU daily for 4 months
Intervention Type
Dietary Supplement
Intervention Name(s)
Vitamin A palmitate
Intervention Description
Vitamin A palmitate, 15,000 IU daily for 4 months
Primary Outcome Measure Information:
Title
Change in dark-adapted full-field visual field sensitivity
Description
Dark-adapted full-field visual field sensitivity will be measured using the Medmont dark-adapted chromatic perimeter.
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in dark-adapted macular visual field sensitivity
Description
Dark-adapted macular visual field sensitivity will be measured using the Medmont dark-adapted chromatic perimeter.
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in dark adaptometry
Description
Dark adaptometry will be measured using the MacuLogix AdaptDx dark adaptometer.
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Secondary Outcome Measure Information:
Title
Change in best corrected visual acuity
Description
Best corrected visual acuity will be measured using the ETDRS chart
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in low luminance visual acuity
Description
Low luminance visual acuity will be measured using the ETDRS chart in low luminance conditions
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in full-field light-adapted visual field sensitivity
Description
Light-adapted full-field visual field sensitivity will be measured using the Octopus 172-point GATE full-field semi-automated kinetic perimetry (SKP)
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in light-adapted macular visual field sensitivity
Description
Light-adapted macular visual field sensitivity will be measured using the Centervue MAIA confocal macular microperimeter
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in retinal pigmented epithelium (RPE) atrophy by optical coherence tomography
Description
Retinal pigmented epithelium (RPE) atrophy will be measured using the Spectralis macular spectral domain optical coherence tomography (SD-OCT) with and without enhanced depth imaging (EDI)
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in retinal pigmented epithelium (RPE) atrophy by color photography
Description
Retinal pigmented epithelium (RPE) atrophy will be measured using the Optos wide-field color fundus photography (WF-CFP)
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in retinal pigmented epithelium (RPE) atrophy by fundus autofluorescence
Description
Retinal pigmented epithelium (RPE) atrophy will be measured using the Optos wide-field fundus auto-fluorescence (WF-FAF)
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in retinal pigmented epithelium (RPE) atrophy by fundoscopy
Description
Retinal pigmented epithelium (RPE) atrophy will be assessed by slit lamp biomicroscopy
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period
Title
Change in liver function
Description
Liver function profile will be measured by laboratory using participant serum samples
Time Frame
Measurements at 0, 4, and 8 months
Title
Change in serum vitamin A levels
Description
Serum vitamin A levels will be measured by laboratory using participant serum samples
Time Frame
Measurements at 0, 4, and 8 months. The 0 months measurement will serve as the baseline. The 4 month measurement will assess change due to vitamin A supplementation. The 8 month measurement will assess reversal of this change following washout period

10. Eligibility

Sex
Male
Gender Based
Yes
Gender Eligibility Description
Choroideremia is an X-linked condition that affects males almost exclusively.
Minimum Age & Unit of Time
15 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
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
Facility Information:
Facility Name
Duke Eye Center
City
Durham
State/Province
North Carolina
ZIP/Postal Code
27710
Country
United States

12. IPD Sharing Statement

Plan to Share IPD
No

Learn more about this trial

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

We'll reach out to this number within 24 hrs