The Short-term Effects of Simvastatin on the Vision of Males Affected by Choroideremia

Study Overview
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Brief Summary
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Primary objective: To examine the short-term effects of of simvastatin on the vision on males with choroideremia, evaluated by full-field scotopic threshold testing. The investigators hypothesize that they will see a reversible decrease in the dark-adapted vision in participants taking simvastatin.

Official Title
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A Repeated Measures Study of Simvastatin on Choroideremia: Simvastatin Intervention and Reversal in Choroideremia Patients and Age-matched Controls.

Conditions
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Choroideremia

Intervention / Treatment
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* Drug: Simvastatin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participant is willing and able to give informed consent for participation in the study Male Diagnosed with choroideremia and in good health Willing to allow his general practitioner and consultant, if appropriate, to be notified of participation in the study Over age of 18 years Exclusion Criteria: Female Significant health disease, disorder, or medication, which, in the opinion of the investigator, would put the patient at risk if he were to take simvastatin Already taking simvastatin or another statin

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CHM<br>Administration of 40mg simvastatin daily, orally for 5 weeks (4-6 weeks window), followed by 5 week (4-6 week window) washout period. | Drug: Simvastatin<br>* Simvastatin 40mg daily by mouth for 5 weeks (4-6 week window) followed by 5 week washout period (4-6 week window).<br>* Other names: Zocor;|
| Active Comparator: Age-matched controls<br>Administration of 40mg simvastatin daily, orally for 5 weeks (4-6 weeks window), followed by 5 week (4-6 week window) washout period. | Drug: Simvastatin<br>* Simvastatin 40mg daily by mouth for 5 weeks (4-6 week window) followed by 5 week washout period (4-6 week window).<br>* Other names: Zocor;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Full-field scotopic threshold | Full-field scotopic threshold measured at 4-6 weeks after simvastatin administration. | 5 weeks (4-6 weeks) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Microperimetry, OCT, fundus autofluorescence, ERG, VA | Correlation of retinal structure and function with changes in FST after administration of simvastatin. | 5 weeks (4-6 weeks) | 
| Microperimetry, OCT, fundus autofluorescence, ERG, VA | Correlation of retinal structure and function with changes in FST after washout of simvastatin. | 5 weeks (4-6 weeks) | 
| Full-field scotopic threshold | Full-field scotopic threshold after washout of simvastatin. | 5 weeks (4-6 weeks) |