Last updated on March 2020

Study of RS1 Ocular Gene Transfer for X-linked Retinoschisis


Brief description of study

Background
  • X-linked juvenile retinoschisis (XLRS) is caused by changes in the RS1 gene. These changes cause abnormal function of the eye protein retinoschisin. Without normal retinoschisin, the layers of the retina split and vision is lost. Researchers want to try to introduce a healthy RS1 gene into eye cells, to see if this helps retinal cells make healthy retinoschisin. They will put the gene in a virus. The gene and virus package is known as a gene transfer vector (AAV-RS1 vector).
    Objectives
  • To see if the AAV-RS1 vector is safe to use in people.
    Eligibility
  • Adults 18 and older with a mutation of the RS1 gene, 20/63 vision or worse in one eye, and XLRS.
    Design
  • Participants will be screened with genetic tests to confirm XLRS. They will have a medical history and physical and eye exams.
  • At visits 1-2, participants will have some or all of the following:
  • Medical history
  • Physical exam
  • Blood and urine tests
  • Tuberculosis skin test
  • Eye exam
  • Vision tests (for one test an intravenous line will be placed in the arm. A dye will be injected that will travel to the blood vessels in the eye).
  • At visit 3, the AAV-RS1 vector will be injected with a needle in the study eye. Participants pupils will be dilated. They will get numbing eye drops.
  • Visits 4-13 will occur in the 18 months after gene transfer. Many of the above tests will be repeated. Participants will discuss any side effects.
  • Visits 14-17 will occur yearly between years 2 and 5.
  • After year 5, participants will be contacted yearly by phone for up to 15 years.

Detailed Study Description

Objective: To evaluate the safety and tolerability of ocular AAV-RS1 vector (AAV8-scRS/IRBPhRS) gene transfer to the retina of participants affected with X-linked juvenile retinoschisis (XLRS).

Study Population: Male participants affected with XLRS will receive ocular gene transfer. A maximum of up to 24 participants may be enrolled.

Design: This is a Phase I/IIa, prospective, dose escalation, single-center study. One eye of each participant will receive the AAV-RS1 gene vector application by intravitreal injection. Participants will be closely monitored in conjunction with DSMC oversight. Participants will be followed for 18 months after which they will continue to be followed for up to 15 years after enrollment, or per FDA requirements, for further safety analysis.

Outcome Measures: The primary outcome is the safety of ocular AAV-RS1 vector as determined from assessment of retinal function, ocular structure and occurrence of adverse events and laboratory tests. Secondary outcomes include changes in visual function, electroretinogram (ERG) responses, visual field measurements, retinal imaging with optical coherence tomography (OCT), and the formation of anti-AAV and anti-RS1 antibodies.

Statistics: No formal sample size calculations are used in this Phase I/IIa dose-escalation study.

Clinical Study Identifier: NCT02317887

Find a site near you

Start Over