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NCT00447993 · ClinicalTrials.gov registry record · Phase 2
A Study of Encapsulated Cell Technology (ECT) Implant for Patients With Late Stage Retinitis Pigmentosa
A Phase 2 study, sponsored by Neurotech Pharmaceuticals.
- Completed
- Registry status
- Phase 2
- Development phase
- 67
- Enrollment target
NCT00447993: Completed Phase 2 study, sponsored by Neurotech Pharmaceuticals.
NCT00447993 is a Phase 2 study that has completed, run by Neurotech Pharmaceuticals. The registered enrollment target is 67 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (50% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00447993, a Phase 2 study, has completed, sponsored by Neurotech Pharmaceuticals.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 67 participants
- Enrollment target
Study Summary
The purpose of this study is to look at the safety and effectiveness of CNTF implants on vision in persons with retinitis pigmentosa, Usher type II \& III, and Choroideremia. This research is being done because there are no effective therapies for people with these retinal degenerations. They are genetic disorders that affect our ability to see at night, and later cause tunnel vision and loss of central vision. Retinal degenerations affect the retina, a light sensitive layer of cells in the back of the eye. Slowly over time, these cells die and cause permanent loss of vision. The implant is a small capsule that contains human retinal pigment epithelium cells. These cells have been given the ability to make CNTF and release it through the capsule membrane into the surrounding fluid. This study will look at the effect of the implant on vision loss by retinitis pigmentosa, Usher type II \& III, and Choroideremia. In this study, two different CNTF dose levels will be used: a high dose and a low dose in one eye, as well as a sham (or placebo) surgery in the other eye.
Primary Outcome
The primary efficacy endpoint was the proportion of patients demonstrating an improvement in best-corrected visual acuity (BCVA), defined as an increase of 10 letters or more at the 1-Year post-implant visit (pre-explant, if explant is completed). No response is defined as an improvement of \<10 letters.
Interventions
- COMBINATION_PRODUCT Low Dose NT-501
- COMBINATION_PRODUCT High Dose NT-501
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 67 participants |
| Start Date | 2007-01-08 |
| Est. Completion | 2009-05-26 |
| Phase | Phase 2 |
What the finished NCT00447993 record still lists
NCT00447993 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 67 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (50% lower).
The record links to 0 conditions, and to 2 interventions - of which Low Dose NT-501 is the first listed.
NCT00447993 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00447993 about?
NCT00447993 is a clinical study titled "A Study of Encapsulated Cell Technology (ECT) Implant for Patients With Late Stage Retinitis Pigmentosa". The purpose of this study is to look at the safety and effectiveness of CNTF implants on vision in persons with retinitis pigmentosa, Usher type II \& III, and Choroideremia. This research is being done because there are no effective therapies for people with these retinal degenerations. They are ge...
What is the current status of trial NCT00447993?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 67 participants. The study started on 2007-01-08. Estimated completion is 2009-05-26.
What interventions are being tested in trial NCT00447993?
The interventions under investigation include: Low Dose NT-501 (COMBINATION_PRODUCT), High Dose NT-501 (COMBINATION_PRODUCT).
Who is sponsoring clinical trial NCT00447993?
This trial is sponsored by Neurotech Pharmaceuticals, which has 13 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00447993's enrollment target sits among peer trials
67 974th of 2000 higher than 1,026 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 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.
Source ClinicalTrials.gov registry export · 2026-08-08
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