Studying a Potential Protective Effect of L-Dopa on Retinitis Pigmentosa

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the effect of L-Dopa on the progression of retinitis pigmentosa.

Detailed Description
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Retinitis pigmentosa is a group of progressive hereditary diseases that diffusely affects the functioning of photoreceptors and the pigment epithelium. It may be speculated that a protective effect on the pigment epithelium, as it is supposed for L-Dopa, can slow the progression of the disease or even lead to an, at least transient, improvement of visual functions. To evaluate the effect of L-Dopa on retinitis pigmentosa progression, visual acuity, electroretinogram and visual field will be preformed regularly.

Official Title
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The Effect of L-Dopa on the Progression of Retinitis Pigmentosa

Conditions
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Retinitis Pigmentosa

Intervention / Treatment
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* Drug: levodopa-carbidopa


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All confirmed cases of retinitis pigmentosa VA of 20/400 or better Exclusion Criteria: Advanced stages of retinitis pigmentosa with poor best corrected visual acuity (less than 20/400) co-existing eye morbidities interfering with retinitis pigmentosa (glaucoma, retinal detachment...) Flat electroretinogram Intolerance or counterindication to drug Unability for long-term follow-up

Ages Eligible for Study
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Minimum Age: 10 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Treatment<br>This is a single armed study. All patients included will receive treatment. Control will happen with data from the same patients before they received treatment. patients will receive sinemet 200/50 1/2 tablet (levodopa-carbidopa 100/25) b.i.d for two days and then will be increased to t.i.d. for 6 months. | Drug: levodopa-carbidopa<br>* sinemet 200/50 1/2 tablet b.i.d. for 2 days and then t.i.d for 6 months<br>* Other names: Sinemet 200/50;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Electroretinogram | the electric response to light stimuli of the retina, in millivolt, will be measured. The electroretinogram shows a-waves (elicit information about the function of the photoreceptors) and b-waves (elicit information about other neurosensory structure of the retina) | Baseline, 1 year, 2 years, 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Visual Acuity | Visual acuity will be measured using Snellen chart | Baseline, 6 months, 1 year, 2 years, 5 years | 
| Change in Visual Field | Using 24-2 Humphrey Visual Field Analyzer, the progress in visual field defect will be measured, comparing mean deviation (dB) and pattern standard deviation (dB) | Baseline, 1 year, 2 years, 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Retinitis Pigmentosa, Levodopa