Clinical Characterization on PDE6A-related Retinitis Pigmentosa in Preparation to a Gene Therapy Trial

Sponsor

STZ eyetrial (Other)

Overall Status

Enrolling by invitation

CT.gov ID

NCT02759952

Collaborator

(none)

Enrollment

Location

155

Duration (Months)

0.3

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Mutations in the PDE6A gene - encoding the -subunit of the rod cGMP-phosphodiesterase - account for 1% of autosomal recessive retinitis pigmentosa (arRP) through impaired regulation of cGMP levels in the rod outer segment. This study aims for a detailed clinical characterization of patients with PDE6A mutations in preparation of a clinical gene replacement study (phase I/II safety trial).

Condition or Disease	Intervention/Treatment	Phase
Retinitis Pigmentosa

Detailed Description

Retinitis pigmentosa (RP) is a clinically and genetically heterogenous group of hereditary retinal disorders, being one of the most common types of retinal degenerations with a prevalence of 1:4000. More than 45 genes have been associated with RP so far, whose defects cause a progressive loss of rod photoreceptor function, followed by cone photoreceptor dysfunction often leading to complete blindness. Mutations in the PDE6A gene - encoding the -subunit of the rod cGMP-phosphodiesterase - account for 1% of autosomal recessive retinitis pigmentosa (arRP) through impaired regulation of cGMP levels in the rod outer segment.

With the help of improved genetic and functional diagnostic tools an early recognition and differentiation has become possible. Still, up to date no established therapy is available, therefore, social and professional consequences are essential tasks to deal with. The modern ophthalmological functional diagnostic tools enable a precise characterisation and early recognition of such retinal diseases. The detailed results and information can help to extend the understanding of the pathological mechanisms involved in these diseases.

In this study the investigators intend to investigate patients with a genetically confirmed diagnosis of Retinitis pigmentosa due to PDE6A mutations hereby assessing the function and structure of the retina with an extensive battery of tests.

Study Design

Study Type:

Observational

Anticipated Enrollment :

50 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

Clinical Characterization on PDE6A-related Retinitis Pigmentosa in Preparation to a Gene Therapy Trial: An Observational Study

Study Start Date :

Jan 1, 2013

Anticipated Primary Completion Date :

Dec 1, 2025

Anticipated Study Completion Date :

Dec 1, 2025

Outcome Measures

Primary Outcome Measures

best corrected visual acuity in both eyes [3 years]
kinetic visual field in both eyes [3 years]
central retinal thickness in both eyes [3 years]

Secondary Outcome Measures

multifocal ERG responses in both eyes [3 years]
colour vision in both eyes [3 years]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 80 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Retinitis pigmentosa patients with genetically confirmed mutations in the PDE6A-gene
written informed consent

Exclusion Criteria:

severe general disease, that would make longer examinations not possible
patients who cannot give written informed consent independently

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Institute for Ophthalmic Research, University Tübingen, Germany	Tübingen	Baden-Württemberg	Germany	72076

Sponsors and Collaborators

STZ eyetrial

Investigators

Principal Investigator: Ditta Zobor, MD, PhD, Institute for Ophthalmic Research, University Tübingen, Germany
Principal Investigator: Susanne Kohl, PhD, Institute for Ophthalmic Research, University Tübingen, Germany