RUSH1F: Rate of Progression of PCDH15-Related Retinal Degeneration in Usher Syndrome 1F

Sponsor

Jaeb Center for Health Research (Other)

Overall Status

Recruiting

CT.gov ID

NCT04765345

Collaborator

Usher 1F Collaborative (Other), Marjorie C. Adams Foundation (Other)

Enrollment

Locations

45.8

Anticipated Duration (Months)

Patients Per Site

0.1

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The overall goal of this project, co-funded by the Foundation Fighting Blindness and the USHER 1F Collaborative is to characterize the natural history of disease progression in patients with PCDH15 mutations in order to accelerate the development of outcome measures for clinical trials.

Condition or Disease	Intervention/Treatment	Phase
Retinal Degeneration Retinitis Pigmentosa Eye Diseases, Hereditary

Detailed Description

This natural history study of patients with PCDH15 disease-causing variants will accelerate the development of outcome measures for clinical trials. Sensitive, reliable outcome measures of retinal degeneration will greatly facilitate development of treatments for retinitis pigmentosa due to PCDH15 disease-causing variants. Together these approaches are expected to have an impact on understanding PCDH15 related retinal degeneration, developing experimental treatment protocols, and assessing their effectiveness.

The goals and expected impact of this natural history study are to:

Describe the natural history of retinal degeneration in patients with biallelic disease-causing variants in the PCDH15 gene
Contribute to the identification of sensitive structural and functional outcome measures to use for future multicenter clinical trials in PCDH15 related retinal degeneration
Contribute to the identification of populations for future clinical trials of investigative treatments for PCDH15 related retinal degeneration

Study Objectives

The primary objectives of the natural history study are to:

Characterize the natural history of retinal degeneration associated with biallelic pathogenic mutations in the PCDH15gene over 4 years, as measured using functional, structural, and patient-reported outcome measures
Explore whether structural outcome measures can be validated as surrogates for functional outcomes in individuals with biallelic pathogenic mutations in the PCDH15 gene
Explore possible risk factors (genotype, phenotype, environmental, and comorbidities) for progression of the outcome measures at 4 years in individuals with biallelic pathogenic mutations in the PCDH15 gene
Explore variability and symmetry of left and right eye outcomes over 4 years in individuals with biallelic pathogenic mutations in the PCDH15 gene

Study Design

Study Type:

Observational

Anticipated Enrollment :

40 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

Rate of Progression of PCDH15-Related Retinal Degeneration in Usher

Actual Study Start Date :

Jun 8, 2021

Anticipated Primary Completion Date :

Apr 1, 2025

Anticipated Study Completion Date :

Apr 1, 2025

Arms and Interventions

Arm	Intervention/Treatment
Vision Cohort 1 ~25 participants with the better eye Screening Visit visual acuity ETDRS letter score of 54 or more [approximate Snellen equivalent 20/80 or better] and visual field diameter 10 degrees or more in every meridian of the central field. The better eye is defined as the eye with better Screening Visit ETDRS VA. If both eyes have the same VA (defined as the same Snellen equivalent), then the determination will be made at investigator discretion as the eye with better fixation or clearer ocular media to permit highest quality retinal imaging. The visual field (VF) is defined as the clinically determined kinetic VF III4e performed within the last 18 months prior to or including the Screening Visit date.
Vision Cohort 2 ~15 participants with the better eye Screening Visit visual acuity ETDRS letter score of 19-53 [approximate Snellen equivalent 20/100 - 20/400] or (visual acuity ETDRS letter score of 54 or more [approximate Snellen equivalent 20/80 or better] and visual field diameter less than 10 degrees in any meridian of the central field). The better eye is defined as the eye with better Screening Visit ETDRS VA. If both eyes have the same VA (defined as the same Snellen equivalent), then the determination will be made at investigator discretion as the eye with better fixation or clearer ocular media to permit highest quality retinal imaging. The visual field (VF) is defined as the clinically determined kinetic VF III4e performed within the last 18 months prior to or including the Screening Visit date.

Arm

Intervention/Treatment

Vision Cohort 1

~25 participants with the better eye Screening Visit visual acuity ETDRS letter score of 54 or more [approximate Snellen equivalent 20/80 or better] and visual field diameter 10 degrees or more in every meridian of the central field. The better eye is defined as the eye with better Screening Visit ETDRS VA. If both eyes have the same VA (defined as the same Snellen equivalent), then the determination will be made at investigator discretion as the eye with better fixation or clearer ocular media to permit highest quality retinal imaging. The visual field (VF) is defined as the clinically determined kinetic VF III4e performed within the last 18 months prior to or including the Screening Visit date.

Vision Cohort 2

~15 participants with the better eye Screening Visit visual acuity ETDRS letter score of 19-53 [approximate Snellen equivalent 20/100 - 20/400] or (visual acuity ETDRS letter score of 54 or more [approximate Snellen equivalent 20/80 or better] and visual field diameter less than 10 degrees in any meridian of the central field). The better eye is defined as the eye with better Screening Visit ETDRS VA. If both eyes have the same VA (defined as the same Snellen equivalent), then the determination will be made at investigator discretion as the eye with better fixation or clearer ocular media to permit highest quality retinal imaging. The visual field (VF) is defined as the clinically determined kinetic VF III4e performed within the last 18 months prior to or including the Screening Visit date.

Outcome Measures

Primary Outcome Measures

Change in Visual Field Sensitivity [Baseline (all Vision Cohort 1 and 2 participants will complete two tests at baseline. The results will be compared according to the visual field criteria to determine if a third test is needed), 12Month, 24Month, 36Month, and 48Month]
measured by static perimetry with quantitative, topographic analysis (Hill of Vision) and assessed by a central reading center
Change in Best Corrected Visual Acuity [Screening, Baseline, 12Month, 24Month, 36Month, and 48Month]
Early Treatment of Diabetic Retinopathy Study (ETDRS) Best corrected visual acuity (BCVA) letter score as measured on the Electronic Visual Acuity (EVA) system or ETDRS charts. Letter score range values=0-100 (with higher values = better and lower values = worse.) Berkeley Rudimentary Vision Test (BRVT) will be used for patients unable to see letters.
Change in Mean Retinal Sensitivity [Baseline (all Vision Cohort 1 and 2 participants will complete two tests at baseline. The results will be compared according to the visual field criteria to determine if a third test is needed), 12Month, 24Month, 36Month, and 48Month]
Measured by fundus-guided microperimetry (MP) and assessed by a central reading center at selected sites with requisite equipment.
Change in Full-field Retinal Sensitivity [Baseline, 12Month, 24Month, 36Month, and 48Month]
Measured by full-field stimulus threshold (FST) testing to blue, white and red stimuli.
Change in Best Corrected Low Luminance Visual Acuity (LLVA) [Screening, Baseline, 12Month, 24Month, 36Month, and 48Month]
Measured by Letter Score. Letter score range values=0-100 (with higher values = better and lower values = worse.)
Change in Contrast Sensitivity Function (CSF) [Baseline, 12Month, 24Month, 36Month, and 48Month]
Measured by the CSV-1000E VectorVision chart
Change in ellipsoid zone (EZ) area [Baseline, 12Month, 24Month, 36Month, and 48Month]
Measured by spectral domain optical coherence tomography (SD-OCT) and assessed by a central reading center.

Secondary Outcome Measures

Explore qualitative categorization of Fundus Autofluorescence (FAF) pattern [Baseline, 12Month, 24Month, 36Month, and 48Month]
Assessed by a central reading center.
Explore quantitative measures of FAF [Baseline, 12Month, 24Month, 36Month, and 48Month]
Assessed by a central reading center.

Other Outcome Measures

Patient Reported Outcomes (Adults 18 years or older) [Baseline, 24Month, and 48Month]
Measured by Michigan Retinal Degeneration Questionnaire (MRDQ) MRDQ - consists of 59 items using categories: : ''None: I do not have trouble with this,'' ''A little difficulty: I notice a problem, but I do not struggle,'' ''Moderate difficulty: I struggle but I can still do this,'' ''Extreme difficulty : I struggle a lot and sometimes I cannot do this,'' and ''N/A for non-vision reasons: I do not do this.'
Patient Reported Outcomes (Adults 18 years or older) [Baseline, 24Month, and 48Month]
Measured by Patient-Reported Outcomes Measurement Information System (PROMIS®-29)
Patient Reported Outcomes (less than 18 years): [Baseline, 24Month, and 48Month]
L. V. Prasad-Functional Vision Questionnaire (LVP-FVQ II) The LVP-FVQ II consists of 23 items using 3 categories: 1, no difficulty; 2, some difficulty; 3, a lot of difficulty

Eligibility Criteria

Criteria

Ages Eligible for Study:

8 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Participants must meet all the following inclusion criteria at the Screening Visit in order to be eligible to enroll into the genetic screening phase.

Willing to participate in the study and able to communicate consent during the consent process
Ability to return for all study visits over 48 months
Age ≥ 8 years
Not planning to enroll in an experimental clinical trial for the treatment of PCDH15 for the duration of this study
Must meet one of the Genetic Screening Criteria, defined below:

Screening Group A: At least 2 disease-causing variants in the PCDH15 gene which are homozygous or heterozygous in trans, based on a report from a clinically certified lab (or a report from a research lab that has been pre- approved by the Genetics Committee)
Screening Group B: Only 1 disease-causing variant in the PCDH15 gene, based on a report from a clinically certified lab (or a report from a research lab which has been pre-approved by the Genetics Committee)
Screening Group C: At least 2 disease-causing variants in the PCDH15 gene which are unknown phase, based on a report from a clinically certified lab (or a report from a research lab which has been pre-approved by the Genetics Committee)

Note pertaining to all Screening Groups: if a participant has a variant(s) of unknown significance, he/she would still qualify if there is at least 1 disease-causing variant(s) on the PCDH15 gene.

Ocular Inclusion Criteria

Both eyes must meet all the following at the Screening Visit for a participant to be eligible to enroll into the genetic screening phase.

Clinical diagnosis of retinal dystrophy
Clear ocular media and adequate pupil dilation to permit good quality photographic imaging

Exclusion Criteria:

Participants must not meet any of the following exclusion criteria at the Screening Visit in order to be eligible to enroll into the genetic screening phase.

Mutations in genes that cause autosomal dominant retinitis pigmentosa (ADRP), X-linked retinitis pigmentosa (RP), or presence of biallelic mutations in autosomal recessive RP/retinal dystrophy genes other than PCDH15
Expected to enter experimental treatment trial at any time during this study
History of more than 1 year of cumulative treatment, at any time, with an agent associated with pigmentary retinopathy (including hydroxychloroquine, chloroquine, thioridazine, and deferoxamine)

Note: Pregnant women are not being specifically excluded from participation.

Ocular Exclusion Criteria

If either eye has any of the following at the Screening Visit, the participant is not eligible to enroll into the genetic screening phase.

Current vitreous hemorrhage
Current or any history of tractional or rhegmatogenous retinal detachment
Current or any history of (e.g., prior to cataract or refractive surgery) spherical equivalent of the refractive error worse than -8 Diopters of myopia
History of intraocular surgery (e.g., cataract surgery, vitrectomy, penetrating keratoplasty, or LASIK) within the last 3 months
Current or any history of confirmed diagnosis of glaucoma (e.g., based on glaucomatous VF changes or nerve changes, or history of glaucoma filtering surgery)
Current or any history of retinal vascular occlusion or proliferative diabetic retinopathy
History or current evidence of ocular disease that, in the opinion of the investigator, may confound assessment of visual function
History or evidence of active treatment for retinitis pigmentosa that could affect the progression of retinal degeneration, including:
Any use of ocular stem cell or gene therapy
Any treatment with ocriplasmin
Treatment with an ophthalmic oligonucleotide within the last 9 months (last treatment date is less than 9 months prior to Screening Visit date)
Treatment with any other product within five times the expected half-life of the product (time from last treatment date to Screening Visit date is at least 5 times the half-life of the given product)
Treatment with Ozurdex (dexamethasone), Iluvien or Yutiq (fluocinolone acetonide) intravitreal implant

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	University of California, San Francisco	San Francisco	California	United States	94143-0344
2	University of Kentucky, Advanced Eye Care	Lexington	Kentucky	United States	40506
3	The Johns Hopkins Wilmer Eye Institute	Baltimore	Maryland	United States	21287
4	Hospital for Sick Children	Toronto	Ontario	Canada
5	University of Tubingen	Tübingen		Germany
6	Haddassah Medical Center	Jerusalem		Israel
7	Radboud University	Nijmegen		Netherlands
8	University Hospital Basel	Basel		Switzerland	4031