Choroideremia
Conditions
Keywords
REP1, Retina, Retinal Degeneration, Retinal Dystrophy, Natural History
Brief summary
The objective of this natural history study is to gain a better understanding of the progression of choroideremia (CHM) and add to the knowledge base for this rare disease.
Detailed description
This study was previously posted by NightstaRx Ltd. In October 2020, sponsorship of the trial was transferred to Biogen.
Interventions
None listed
Sponsors
NightstaRx Ltd, a Biogen Company
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Key Inclusion Criteria: * Are willing and able to provide informed consent for participation in the study. * Have a clinical phenotype and confirmed genetic diagnosis of CHM. * Have active disease clinically visible within the macular region. * Are willing and able to undergo ophthalmic examinations once every 4 months for up to 20 months. * Have a BCVA better than or equal to 6/60 (20/200; decimal 0.1; LogMAR 1.0; 34-38 ETDRS letters) in at least one eye. Key
Exclusion criteria
* Have a history of amblyopia in the eligible eye. * Have any other significant ocular or non-ocular disease/disorder in the eligible eye which, in the opinion of the investigator, may put the subject at risk because of participation in the study, influence the results of the study or influence the subject's ability to participate in the study. * Have participated in an interventional research study in the past 6 months. NOTE: Other protocol defined Inclusion/
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Best-Corrected Visual Acuity (BCVA) using the Early Treatment Diabetic Retinopathy Study (EDTRS) | Up to Month 20 | BCVA will be assessed for both eyes using the Early Treatment of Diabetic Retinopathy Study (ETDRS) visual acuity (VA) chart. BCVA test should be performed prior to pupil dilation, and distance refraction should be carried out before BCVA is measured. Initially, letters are read at a distance of 4 meters from the chart. If \<20 letters are read at 4 meters, testing at 1 meter should be performed. BCVA is to be reported as number of letters read correctly by the participant using the ETDRS Scale (ranging from 0 to 100 letters) in the study eye. The lower the number of letters read correctly on the eye chart, the worse the vision (or visual acuity). An increase in the number of letters read correctly means that vision has improved. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change from Baseline in Color Vision | Baseline up to Month 12 | Colour vision will be tested prior to pupil dilation. Each eye will be tested separately and in the same order. |
| Change from Baseline in Visual Fields | Baseline up to Month 12 | The progression of defects in visual fields will be assessed in both eyes using perimetry equipment. |
| Change from Baseline in Contrast Sensitivity | Baseline up to Month 12 | Contrast sensitivity will be measured for both eyes, prior to pupil dilation, using a Pelli Robson chart. |
| Change from Baseline in Reading Performance using International Reading Speed Texts (IReST) | Baseline up to Month 12 | Reading performance will be evaluated prior to pupil dilation. |
| Change from Baseline in Area of Viable Retinal Tissue Using Fundus Autofluorescence | Baseline up to Month 20 | Fundus Autofluorescence will be performed after dilation of the participant's pupil to assess changes in the area of viable retinal tissue. |
| Change from Baseline in Retinal Sensitivity Using Microperimetry | Baseline up to Month 20 | Macular analyser integrity assessment (MAIA) microperimetry will be conducted for both eyes to assess changes in retinal sensitivity within the macula. |
| Change from Baseline in Retinal Thinning Using Spectral Domain Optical Coherence Tomography (SD-OCT) | Baseline up to Month 20 | SD-OCT measurements will be performed after dilation of the participant's pupil. |
Countries
Brazil, Canada, Denmark, Finland, France, Germany, Netherlands, United Kingdom, United States
Outcome results
None listed