Safety and Efficacy of rAAV-hRS1 in Patients With X-linked Retinoschisis (XLRS)

A Multiple-Site, Phase 1/2, Safety and Efficacy Trial of a Recombinant Adeno-associated Virus Vector Expressing Retinoschisin (rAAV2tYF-CB-hRS1) in Patients With X-linked Retinoschisis

This study will evaluate the safety and efficacy of a recombinant adeno-associated virus vector expressing retinoschisin (rAAV2tYF-CB-hRS1) in patients with X-linked retinoschisis. Up to 27 participants will be enrolled and 3 dose levels will be evaluated in a dose escalation format.

This will be a non-randomized, open label, Phase 1/2 dose escalation study.

Up to 27 participants will be enrolled. Each participant will receive the study agent by intravitreal injection in one eye on a single occasion. Enrollment will begin with the lowest dose and will proceed to higher doses only after review of safety data by a Data and Safety Monitoring Committee (DSMC). Participants in the dose escalation phase will be ≥ 18 years of age. After the maximum tolerated dose is identified individuals ≥ 6 years of age will be enrolled.

Safety will be measured by the number and proportion of participants experiencing adverse events and immune response to RS1. Efficacy will be measured by evaluation of changes in visual function and schisis cavity size.

Inclusion Criteria include:

1. Retinal disease consistent with a diagnosis of XLRS and documented mutations in the RS1 gene
2. Male individual at least 18 years of age (dose escalation phase) or at least 6 years of age (maximum tolerated dose phase),
3. Able to perform tests of visual and retinal function,
4. Visual acuity specified for each group
5. Not treated with CAIs currently or within 3 months prior to study enrollment,
6. Have acceptable laboratory parameters.

Exclusion Criteria include:

1. Prior receipt of any AAV gene therapy product,
2. Pre-existing eye conditions that would preclude the planned intravitreal injection or interfere with interpretation of study endpoints or complications of vector administration.