Retinitis Pigmentosa Associated With CNGB1 MutationsNCT04639635
CNGB1 and Allied Disorders
An observational study of Retinitis Pigmentosa Associated With CNGB1 Mutations, run by Columbia University at 6 sites in 4 countries.
Trial summary
Mutations in the rod-expressed gene, cyclic nucleotide-gated channel beta subunit (CNGB1) and associated inborn errors in metabolism are causes of retinal disease that causes progressive loss of vision. Retinitis pigmentosa (RP) is a major cause of untreatable blindness associated with CNGB1 (CNGB1-RP). Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Retinitis Pigmentosa Associated With CNGB1 Mutations
- How many people
- 20 participants
- Where
- 6 sitesin 4 countries
- Study dates
- 14 Mar 2019to Feb 2027
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: Patients are expected to present to the clinic at all age groups; enrollment of subjects <18 years of age will be obtained by informed consent in the company of a parent or legal guardian. There will also be no gender-or ethnic/racial specific inclusion criteria. The enrollment of non-English speaking subjects is not expected.
Who may be able to join
- Diagnosis of CNGB1-associated RP by study physician, who are trained retinal specialists in the university clinic
- Must be able to commit to 4 follow-up study visits (3 years)
Who cannot join
None listed.
Trial locations and contacts
6 sites in 4 countries.
6 sites in 4 countries
United States2 sites
Dr. Stephen H. Tsang
New York, New York, 10032
Wills Eye Hospital
Philadelphia, Pennsylvania, 19107
Germany2 sites
Klinikum der Universität München University Eye Hospital, Ludwig-Maximilians-University (LMU) Munich
München, Bavaria, 80336
Eberhard Karls University Tubingen
Tübingen
France1 site
Institut de la Vision/Centre de maladies rares du Centre Hospitalier National Ophtalmologique des Quinze-Vingts
Paris
United Kingdom1 site
Moorfields Eye Hospital NHS Foundation Trust
London
About this study
Official title: Study of CNGB1 Retinitis Pigmentosa and Allied Hereditary Disorders
Mutations in the rod-expressed gene, cyclic nucleotide-gated channel beta subunit (CNGB1) and associated inborn errors in metabolism are causes of retinal disease that causes progressive loss of vision. Retinitis pigmentosa (RP) is a major cause of untreatable blindness associated with CNGB1 (CNGB1-RP). RP involves the death of photoreceptor cells that can be caused by mutations in a number of different genes. Treatment by gene therapy could prevent blindness in cases of inherited retinal dystrophies including RP. In the future RP due to mutations in CNGB1 may be treatable by gene therapy since this form of photoreceptor degeneration involves a slow loss of rod photoreceptor cells. This provides a wide window of opportunity for the identification of patients and initiation of treatment. Our efforts are directed toward developing gene therapy as a treatment. To this end, our objective is to better understand the disease process of CNGB1-RP and other allied inherited disorders so that we can develop clinical tests to measure the outcomes of treatment.
- Being tested
- No intervention, this is a natural history progression study
- Keywords
- Retinitis Pigmentosa, CNGB1, Natural Progression
- Medical subject headings
- Retinitis Pigmentosa
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
No intervention, this is a natural history progression studyOther
The objective is to better understand the disease process of CNGB1-RP so that we can develop clinical tests to measure the outcomes of treatment.
What is being measured
The primary outcome is the main question the study is designed to answer.
We will be looking to identify what the best outcome measurements will be for CNGB1-RP in order to use these measurements in a future clinical trial.
Both structural imaging and functional tests will be used to characterize the natural history progression of CNGB1-RP.
Measured: 2 days, 1 time per year, for 3 years
Medmont Dark Adapted Chromatic (DAC) Automated Perimeter
Measured: 1 time per year, for 3 years
Full-field ERG (ISCEV Protocol)
Measured: 1 time per year, for 3 years
Optical Coherence Tomography (OCT)
Measured: 1 time per year, for 3 years
Fundus Autofluorescence (FAF)
Measured: 1 time per year, for 3 years
Near-infrared fundus autofluorescence (NIR-AF)
Measured: 1 time per year, for 3 years
Quantitative Fundus Autofluorescence (qAF)
Measured: 1 time per year, for 3 years
Secondary outcomes (10)
Best-corrected Visual Acuity (BCVA)
Measured: 1 time per year, for 3 years
Complete Ophthalmic Exam
Measured: 2 time per year, for 3 years
Color Fundus Photos
Measured: 1 time per year, for 3 years
MAIA Microperimetry
if available
Measured: 1 time per year, for 3 years
NIDEK Microperimetry
if available
Measured: 1 time per year, for 3 years
Goldman Kinetic Visual Field
Measured: 1 time per year, for 3 years
Light-adapted Static Perimetry
Measured: 1 time per year, for 3 years
Panel D-15 Colour Vision (desat.)
Measured: 1 time per year, for 3 years
Dark-adapted Chromatic Perimetry
Measured: 1 time per year, for 3 years
Full-field Stimulus Testing (FST)
Optional
Measured: 1 time per year, for 3 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted20 Nov 2020
- Study start14 Mar 2019
- Primary completionFeb 2027 (estimated)
- Study completionFeb 2027 (estimated)
Why it stopped: IRB renewal lapsed
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Retinitis Pigmentosa Associated With CNGB1 MutationsStudies of the same condition, open and under way.
- More trials run by Columbia UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case only
- Time perspective
- Prospective
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Columbia University
- Sponsor type
- University, hospital or other
- Collaborators
- Michigan State University, Moorfields Eye Hospital NHS Foundation Trust, Universität Tübingen, Wills Eye, La Fondation Voir et Entendre, Ludwig-Maximilians - University of Munich
- Responsible party
- Sponsor
- Investigators
- Stephen Tsang, MD, PhD, Principal investigator, Columbia University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04639635
- Sponsor's protocol ID
- AAAS1160
- Status last verified
- Apr 2026
- First submitted
- 7 Aug 2020
- Last updated
- 13 Apr 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 13 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Study of CNGB1 Retinitis Pigmentosa and Allied Hereditary Disorders
- ClinicalTrials.gov ID
- NCT04639635
- Acronym / sponsor ID
- AAAS1160
- Keywords
- Retinitis Pigmentosa, CNGB1, Natural Progression
- Study type
- Observational
- Recruitment status
- SuspendedReason stopped: IRB renewal lapsed
- Enrolment
- 20 participants (estimated)
- Lead sponsor
- Columbia UniversityUniversity, hospital or other
- Collaborators
- Michigan State University, Moorfields Eye Hospital NHS Foundation Trust, Universität Tübingen, Wills Eye, La Fondation Voir et Entendre, Ludwig-Maximilians - University of Munich
- Study start
- 14 Mar 2019 (actual)
- Primary completion
- Feb 2027 (estimated)
- Study completion
- Feb 2027 (estimated)
- First posted
- 20 Nov 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Mutations in the rod-expressed gene, cyclic nucleotide-gated channel beta subunit (CNGB1) and associated inborn errors in metabolism are causes of retinal disease that causes progressive loss of vision. Retinitis pigmentosa (RP) is a major cause of untreatable blindness associated with CNGB1 (CNGB1-RP). RP involves the death of photoreceptor cells that can be caused by mutations in a number of different genes. Treatment by gene therapy could prevent blindness in cases of inherited retinal dystrophies including RP. In the future RP due to mutations in CNGB1 may be treatable by gene therapy since this form of photoreceptor degeneration involves a slow loss of rod photoreceptor cells. This provides a wide window of opportunity for the identification of patients and initiation of treatment. Our efforts are directed toward developing gene therapy as a treatment. To this end, our objective is to better understand the disease process of CNGB1-RP and other allied inherited disorders so that we can develop clinical tests to measure the outcomes of treatment.
Study design
- Observational model
- Case only
- Time perspective
- Prospective
Who may qualify
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
- Study population
- Patients are expected to present to the clinic at all age groups; enrollment of subjects <18 years of age will be obtained by informed consent in the company of a parent or legal guardian. There will also be no gender-or ethnic/racial specific inclusion criteria. The enrollment of non-English speaking subjects is not expected.
Key inclusion criteria (2 listed)
- Diagnosis of CNGB1-associated RP by study physician, who are trained retinal specialists in the university clinic
- Must be able to commit to 4 follow-up study visits (3 years)
Key exclusion criteria (0 listed)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| No intervention, this is a natural history progression studyThe objective is to better understand the disease process of CNGB1-RP so that we can develop clinical tests to measure the outcomes of treatment. | Other | – |
Primary outcome
We will be looking to identify what the best outcome measurements will be for CNGB1-RP in order to use these measurements in a future clinical trial.
Time frame: 2 days, 1 time per year, for 3 years
Both structural imaging and functional tests will be used to characterize the natural history progression of CNGB1-RP.
Medmont Dark Adapted Chromatic (DAC) Automated Perimeter
Time frame: 1 time per year, for 3 years
Full-field ERG (ISCEV Protocol)
Time frame: 1 time per year, for 3 years
Optical Coherence Tomography (OCT)
Time frame: 1 time per year, for 3 years
Fundus Autofluorescence (FAF)
Time frame: 1 time per year, for 3 years
Near-infrared fundus autofluorescence (NIR-AF)
Time frame: 1 time per year, for 3 years
Quantitative Fundus Autofluorescence (qAF)
Time frame: 1 time per year, for 3 years
10 secondary outcomes
Best-corrected Visual Acuity (BCVA)
Time frame: 1 time per year, for 3 years
Complete Ophthalmic Exam
Time frame: 2 time per year, for 3 years
Color Fundus Photos
Time frame: 1 time per year, for 3 years
MAIA Microperimetry
Time frame: 1 time per year, for 3 years
NIDEK Microperimetry
Time frame: 1 time per year, for 3 years
Goldman Kinetic Visual Field
Time frame: 1 time per year, for 3 years
Light-adapted Static Perimetry
Time frame: 1 time per year, for 3 years
Panel D-15 Colour Vision (desat.)
Time frame: 1 time per year, for 3 years
Dark-adapted Chromatic Perimetry
Time frame: 1 time per year, for 3 years
Full-field Stimulus Testing (FST)
Time frame: 1 time per year, for 3 years
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 13 Apr 2026.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Stephen Tsang, MD, PhD principal investigator
Columbia University
6 sites in 4 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Retinitis Pigmentosa Associated With CNGB1 Mutations, run by Columbia University at 6 sites in 4 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 0 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: paused, as of the sponsor's last update on 13 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in United States, Germany, France, United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
We will be looking to identify what the best outcome measurements will be for CNGB1-RP in order to use these measurements in a future clinical trial. (time frame: 2 days, 1 time per year, for 3 years). The study lists 7 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 13 Apr 2026.