Medical Information Only. Always consult your healthcare provider before enrolling in any clinical trial.
Oral N-acetylcysteine for Retinitis Pigmentosa
NCT05537220 · View on ClinicalTrials.gov ↗
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.
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 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT05537220
The ClinicalTrials.gov registry entry for NCT05537220 describes a study currently listed as active not recruiting. It is categorized as Phase 3, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 485 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Johns Hopkins University, which has 1,517 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
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. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT05537220 reports 20 study locations spanning 13 distinct geographic areas — top geographies include California, Florida, Illinois. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
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. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT05537220?
The interventions under investigation include: Placebo (DRUG), N-acetylcysteine (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT05537220?
This trial is sponsored by Johns Hopkins University, which has 1,517 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
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.
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