Natural Disease Progression in Participants With Choroideremia

Study Overview
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Brief Summary
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The primary objective of this study is to quantify disease progression measured by best corrected visual acuity (BCVA) in the real-world setting among Choroideremia (CHM) participants. The secondary objectives are to describe demographic and baseline clinical characteristics among CHM participants and to match CHM participants in the Intelligent Research in Sight (IRIS®) Registry to Biogen's investigator sponsored trial (IST) study population using propensity score matching.

Detailed Description
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This study is a retrospective cohort study of CHM eyes and participants which will include all eligible participants and eyes with the first documented diagnosis of CHM from July 1st, 2013 to December 31st, 2019 that meet the study criteria. This study will be conducted using data from American Academy of Ophthalmology's (AAO) IRIS® Registry which captures CHM participant's demographics, clinical characteristics and clinical outcomes from 2013.

Official Title
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A Retrospective Cohort Analysis of the Natural Disease Progression of Patients With Choroideremia in Real-World Clinical Practice

Conditions
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Choroideremia

Intervention / Treatment
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* Other: No Intervention


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Cohort 1: All CHM Participants Participants with a documented diagnosis of CHM identified by the presence of International Classification of Diseases (ICD)-9/10 or SNOMED coding: ICD-9: 363.55 ICD-10: H31.2 SNOMED-CT: 75241009 Cohort 2: Trial-Matched CHM Participants Male participants with a documented diagnosis of CHM identified by the presence of ICD-9/10 or SNOMED coding: ICD-9: 363.55 ICD-10: H31.21 SNOMED-CT: 75241009 Key Exclusion Criteria: N/A NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 10 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cohort 1: Main Cohort<br>All eligible participants with CHM in IRIS Registry will be included. | Other: No Intervention<br>* Administered as specified in the treatment arm.<br>|
| Cohort 2: Trial-Matched Cohort<br>Only male participants with CHM from Cohort 1 to match Biogen's IST study population using propensity score matching will be included. | Other: No Intervention<br>* Administered as specified in the treatment arm.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants with Progression of Best Corrected Visual Acuity (BCVA) in Relation to Age |  | Up to 6 years | 
| Percentage of Participants with Progression of BCVA Over Time After the Baseline BCVA |  | Up to 6 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants with Demographics Described at Baseline | The demographics will include age, sex, race, geographic region and treating provider specialty. | Up to 6 years | 
| Matching Participants with CHM in the IRIS® Registry to Biogen's IST Study Population Using Propensity Score (PS) Matching | A propensity score matching approach will be performed to select eligible male CHM participants from IRIS Registry to match Biogen's IST study population. With the approach, the probability of participating in the IST study given the observed baseline participant characteristics will be estimated for each participant. Propensity score will be estimated using logistic regression and pre-specified baseline covariates including participants demographics and clinical characteristics. The propensity match will be considered adequate if all the variables between the PS-matched CHM cohort and IST study cohort have an absolute value of the standardized mean difference (SMD) in PS-score that is less than 0.1. | Up to 6 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Rare disease, X-linked inherited retinal disorder, Bilateral disease