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NCT05537220 · ClinicalTrials.gov registry record · Phase 3
Oral N-acetylcysteine for Retinitis Pigmentosa
A Phase 3 study of Retinitis Pigmentosa, sponsored by Johns Hopkins University.
- Active
- Registry status
- Phase 3
- Development phase
- 485
- Enrollment target
- 20
- Study locations
NCT05537220: Active Phase 3 study of Retinitis Pigmentosa, sponsored by Johns Hopkins University.
NCT05537220 is a Phase 3 study of Retinitis Pigmentosa that is active but no longer recruiting, run by Johns Hopkins University. The registered enrollment target is 485 participants, above the 248-participant average among 37 other Retinitis Pigmentosa trials with a reported enrollment target (96% higher). The trial reports 20 study locations across 13 states. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05537220, a Phase 3 study of Retinitis Pigmentosa, is active but no longer recruiting, sponsored by Johns Hopkins University.
- ACTIVE NOT RECRUITING
- Registry status
- Phase 3
- Development phase
- 485 participants
- Enrollment target
- 20
- Study locations
Study Summary
Retinitis pigmentosa (RP) is an inherited retinal degeneration caused by one of several mistakes in the genetic code. Such mistakes are called mutations. The mutations cause degeneration of rod photoreceptors which are responsible for vision in dim illumination resulting in night blindness. After rod photoreceptors are eliminated, gradual degeneration of cone photoreceptors occurs resulting in gradual constriction of side vision that eventually causes tunnel vision. Oxidative stress contributes to cone degeneration. N-acetylcysteine (NAC) reduces oxidative stress and in animal models of RP it slowed cone degeneration. In a phase I clinical trial in patients with RP, NAC taken by month for 6 months caused some small improvements in two different vision tests suggesting that long-term administration of NAC might slow cone degeneration in RP. NAC Attack is a clinical trial being conducted at many institutions in the US, Canada, and Europe designed to determine if taking NAC for several years provides benefit in patients with RP.
Primary Outcome
The EZ is a hyperreflective band seen on SD-OCT scans that corresponds to photoreceptors with intact inner and outer segments. In RP patients at the stage of those participating in this trial, the EZ consists primarily of remaining cones with intact inner and outer segments. The EZ width is the length of the EZ on a horizontal SD-OCT scan through the fovea and provides a quantitative measure of surviving cones. The primary outcome measure is the progressive change (loss) in EZ width measured as
Conditions Studied
Interventions
- DRUG Placebo
- DRUG N-acetylcysteine
Study Locations (20)
California
- University of California - Davis, Department of Ophthalmology & Vision Science - Davis
- University of Southern California, Keck School of Medicine - Los Angeles
- University of California - San Francisco, Department of Ophthalmology - San Francisco
- Stanford University, Byers Eye Institute - Stanford
Florida
- Vitreo Retinal Associates - Gainesville
- University of Florida - Jacksonville, UF Health Jacksonville - Jacksonville
- University of Miami, Bascom Palmer Eye Institute - Miami
Illinois
- University Of Illinois At Chicago - Chicago
- Northwestern University - Evanston
Minnesota
- University of Minnesota, Department of Ophthalmology and Visual Neurosciences - Minneapolis
- Mayo Clinic, Department of Ophthalmology - Rochester
Georgia
- Emory University, Emory Eye Center - Atlanta
Iowa
- University of Iowa, Carver College of Medicine - Iowa City
Maryland
- Wilmer Eye Institute- Johns Hopkins University - Baltimore
Massachusetts
- Harvard University, Mass. Eye and Ear - Boston
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 485 participants |
| Start Date | 2023-10-11 |
| Est. Completion | 2030-05 |
| Phase | Phase 3 |
What the registry record for NCT05537220 still lists
NCT05537220 is an interventional study that assigns participants to a tested intervention. The registered 485 participants enrollment target is mid-sized for trials with a published cap, above the 248-participant average among 37 other Retinitis Pigmentosa trials with a reported enrollment target (96% higher).
The record links to 1 condition, with Retinitis Pigmentosa appearing as the primary indexed condition, and to 2 interventions - of which Placebo is the first listed.
NCT05537220 names 20 study sites across 13 states, led by California, Florida, Illinois.
Frequently Asked Questions
What is clinical trial NCT05537220 about?
NCT05537220 is a clinical study titled "Oral N-acetylcysteine for Retinitis Pigmentosa". Retinitis pigmentosa (RP) is an inherited retinal degeneration caused by one of several mistakes in the genetic code. Such mistakes are called mutations. The mutations cause degeneration of rod photoreceptors which are responsible for vision in dim illumination resulting in night blindness. After ro...
What is the current status of trial NCT05537220?
This trial is currently active not recruiting. It is a Phase 3 study. The enrollment target is 485 participants. The study started on 2023-10-11. Estimated completion is 2030-05.
What conditions does trial NCT05537220 study?
This clinical trial studies the following conditions: Retinitis Pigmentosa.
What interventions are being tested in trial NCT05537220?
The interventions under investigation include: Placebo (DRUG), N-acetylcysteine (DRUG).
Who is sponsoring clinical trial NCT05537220?
This trial is sponsored by Johns Hopkins University, which has 1,448 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT05537220 being conducted?
This trial has 20 study locations across California, Florida, Georgia, Illinois, Iowa. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
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Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.
Where NCT05537220's enrollment target sits among peer trials
485 7th of 37 higher than 31 of 37 other Retinitis Pigmentosa trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Retinitis Pigmentosa trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
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