Safety and Efficacy Study of LX103 Treatment of X-Linked Retinoschisis (XLRS)

Study Overview
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Brief Summary
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The goal of this study is to evaluate the safety and efficacy of LX103 treatment of X-linked retinoschisis. This study will enroll subjects aged ≥ 6 years old to receive a single unilateral intravitreal (IVT) injection of LX103 to evaluate its safety and efficacy.

Official Title
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An Open Label Dose Escalation Clinical Trial to Evaluate the Safety and the Efficacy of LX103 in Patients With X-Linked Retinoschisis (XLRS)

Conditions
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X-linked Retinoschisis

Intervention / Treatment
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* Genetic: LX103 Injection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Willing to sign the informed consent, and willing to attend follow-up visits. Male individual at least 6 years of age with a diagnosis of XLRS and documented mutations in the RS1 gene. The study eye must have a best-corrected E-ETDRS visual acuity letter score of less than or equal to 63. Exclusion Criteria: Any eye with disease that would interfere with the fundus examinations. The study eye is receiving topical carbonic anhydrase inhibitor, or has received topical carbonic anhydrase inhibitors in the past three months. The study eye has undergone intraocular surgery within six months prior to enrollment. Participant has uncontrolled hypertension or diabetes.

Ages Eligible for Study
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Minimum Age: 6 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: LX103 Injection<br>Potential doses: 5E10 vg, 0.1 mL/eye/dose (low dose) 1E11 vg, 0.05 mL/eye/dose (high dose) | Genetic: LX103 Injection<br>* Qualified subjects will receive a single unilateral intravitreal injection of LX103 at Day 0 in the trial.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of adverse events (AEs) | Incidence of adverse events (AEs) within 24 weeks of LX103 intravitreal injection at different doses | 24 weeks | 
| Incidence of serious adverse events (SAEs) | Incidence of serious adverse events (SAEs) within 24 weeks of LX103 intravitreal injection at different doses | 24 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean change from baseline in BCVA (LogMAR) in the study eye | ETDRS visual acuity charts will be used to assess BCVA | 24 weeks, 52 weeks | 
| Mean change from baseline in central subfield thickness (CST) in the study eye | Mean change of CST measured using Optical Coherence Tomography (OCT) | 24 weeks, 52 weeks | 
| Change from baseline in Electroretinogram (ERG) parameters in the study eye | Change in dark-adapted 3.0 B-wave amplitude (μV) | 24 weeks, 52 weeks |