An interventional study of Coloured-light torch and Different coloured-light torch in Retinitis Pigmentosa, sponsored by University College, London. Not yet recruiting at 1 site in United Kingdom. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2024-01-25.
Sponsored by University College, London · Not applicable, Interventional, and Basic science
This study will assess the effect of 2 different colours of light on colour vision in adults with retinitis pigments (RP). Participants will be 18 years or above with a genetically confirmed molecular diagnosis of RP. After informed consent, participants will have their letter chart vision and colour vision measured in their study eye. They will then be they will be randomly allocated to one of 2 groups. The study team will not know which group they have been assigned to. Group 1 will be given a coloured-light hand-held torch and be asked to apply it to their study eye for 3 minutes at home each morning between 8 - 10 am for 28 days. Group 2 will be given a different colour hand-held torch and be asked to do the same. All participants will have their letter chart vision and colour vision measured at the end of study on day 28 (+ 7 days).
This is a pilot, randomised, masked, single-site trial designed to assess the effect of coloured light exposure on cone contrast thresholds (CCT) in adults with RP.
70 adults with typical RP in which the underlying genetic cause is known will be recruited from Moorfields Eye Hospital genetics service.
Following informed consent, participants will be invited for a baseline study visit.
At a baseline visit, prior to any light exposure (day 0), participants will undergo Logarithm of the Minimum Angle of Resolution (LogMAR) visual acuity (VA) and CCT measurements performed by an experienced technician according to dedicated standard operating procedures. The order of testing will be as follows:
After baseline assessments have been completed, participants will be randomised to the intervention (n=35) or control group (n=35) by a study nurse. All other study team members will be masked to group allocation.
The intervention group will be provided with a coloured torch and instructed to apply it to their study eye for 3 minutes at home each morning between 8 - 10 am for 28 days. The control group will be provided with a different coloured torch and will be instructed to follow the same protocol. The specific colours have not be disclosed here to protect masking of the study. Participants will be asked to complete a paper diary each day to record whether light was applied, the time and duration of the application and the eye to which light was applied.
The end of trial visit will be scheduled on day 28 (+7 days). Participants will undergo LogMAR VA and CCT measurements by an experienced technician according to standard operating procedures (SOP). The order of testing will be as follows:
278 studies on the registry are indexed under Retinitis Pigmentosa; 72 are open to participants now.
This study's planned enrollment of 70 is above the median of 27 across 179 interventional studies indexed under Retinitis Pigmentosa.
Browse Retinitis Pigmentosa studies →University College, London is the lead sponsor of 651 studies on the registry; 149 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 2 (33%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Coloured light 1 group will be provided with a coloured-light torch and instructed to apply it to their study eye for 3 minutes at home each morning between 8 - 10 am for 28 days.
Device: Coloured-light torch
Coloured light 2 group will be provided with a different coloured-light torch and instructed to apply it to their study eye for 3 minutes at home each morning between 8 - 10 am for 28 days.
Device: Different coloured-light torch
Participant administered, at-home, 3-minute daily morning application (between 8 - 10am) of a coloured-light torch to the study eye.
Participant administered, at-home, 3-minute daily morning application (between 8 - 10am) of a different coloured-light torch to the study eye.
Tritan Colour Contrast Threshold (CCT)
Tritan CCT will be measured using the ChromaTest® platform, a software program which quantifies age-corrected tritan and protan CCT using a Modified Binary Search method. Tritan CCT test endpoint is a continuous variable (units: percentage).
Time frame: Measured at Day 0 and Day 28
Protan CCT
Protan CCT will be measured using the ChromaTest® platform, a software program which quantifies age-corrected tritan and protan CCT using a Modified Binary Search method. Protan CCT test endpoint is a continuous variable (units: percentage).
Time frame: Measured at Day 0 and Day 28
LogMAR Visual Acuity (LogMAR VA)
LogMAR VA will be measured on an electronic LogMAR acuity chart (Test Chart 2020, Thompson Software Solutions, UK), according to a forced-choice procedure.
Time frame: Measured at Day 0 and Day 28
Proportion of participants losing ≥15 letters of LogMAR VA
Proportion of participants losing 15 letters of LogMAR VA or more at day 28 will be reported as a safety outcome.
Time frame: Measured each day (Day 0 through Day 28)
Compliance rate
Compliance rate of application of daily, 3-minute, at-home, participant administered coloured-light exposure is a secondary endpoint. This will be collected through completion of a participant diary.
Time frame: Measured each day (Day 0 through Day 28)
Plan to share: No — Data will not be shared with other researchers
No publications or documents are linked to this record.
Start is estimated for Mar 2024; primary completion for Oct 2024, 7 months later.
Of 30 interventional studies with no phase under Retinitis Pigmentosa, half reached primary completion within 42 months of starting (the median), counting those still running; a quarter within 21 and three quarters within 154. This study's planned 7 months is below that.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Jan 2024. You cannot join it, but the record below documents what was studied.
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