Long-Term Follow Up of CLN6 Batten Disease Subjects Following Gene Transfer

Study Overview
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Brief Summary
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This is a long-term safety and efficacy study in subjects with CLN6 Batten disease who previously received a single intrathecal administration of AT-GTX-501.

Detailed Description
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This is a long-term safety and efficacy study in subjects with CLN6 Batten disease (also know as variant late infantile neuronal ceroid lipofuscinosis associated with mutation(s) in the CLN6 gene [vLINCL6] disease),who previously received a single intrathecal administration of AT-GTX-501. The assessments described in this long-term follow-up (LTFU) study (AT-GTX-501-02) are performed following and in addition to the initial 2 years of post-treatment assessments in the treatment study (AT-GTX-501-01). In this LTFU study, subjects complete safety and efficacy assessments throughout the study's 3-year duration. Combining the duration of the initial treatment study and this LTFU study, the overall duration reflects a follow-up period up-to 5 years since gene transfer via AT-GTX-501. The primary outcome for this study is to assess the long-term safety of AT-GTX-501 in subjects with CLN6 Batten disease. The secondary outcome measure of this study is to assess the long-term efficacy of AT-GTX-501 in subjects with CLN6 Batten disease.

Official Title
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Long-Term Follow-Up of AT-GTX-501 scAAV9 Gene Transfer in Subjects With CLN6 Batten Disease

Conditions
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CLN6, Batten Disease

Intervention / Treatment
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* Genetic: AT-GTX-501


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject received AT-GTX-501 (scAAV9.CB.CLN6) in the study Phase I/IIa Gene Transfer Clinical Trial for Variant Late Infantile Neuronal Ceroid Lipofuscinosis, Delivering the CLN6 Gene by Self-Complementary AAV9. Subject completed or prematurely discontinued from the study Phase I/IIa Gene Transfer Clinical Trial for Variant Late Infantile Neuronal Ceroid Lipofuscinosis, Delivering the CLN6 Gene by Self-Complementary AAV9. Subject has a legally authorized representative who has provided written informed consent and authorization for use and disclosure of personal health information or research-related health information. Exclusion Criteria: None

Ages Eligible for Study
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Minimum Age: 12 Months

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Subjects who received AT-GTX-501 gene transfer<br>Subjects with CLN6 Batten disease who previously received AT-GTX-501 in the preceding study (Study AT-GTX-501-01). | Genetic: AT-GTX-501<br>* No study drug is administered in this study. Subjects who received AT-GTX-501 in a previous trial will be evaluated in this trial for long-term safety and efficacy.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Long-term safety assessment based on Adverse Events (AEs) | All AEs that occur during this study will be classified as treatment-emergent adverse events (TEAEs), as AT-GTX-501 was previously received by all subjects in this study. | up to 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hamburg Scale | The Hamburg scale is an established tool to capture the rate of decline or regression. From the Hamburg Scale, the individual motor and language scores and the motor plus language aggregated score will be summarized. | up to 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Neuronal ceroid lipofuscinosis, NCL, Gene Transfer, vLINCL6