Phase 3 Efficacy and Safety Study of GTX-102 in Pediatric Subjects With Angelman Syndrome (AS)
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Phase
Phase 3
Status
Active, not recruiting
Study type
Interventional
Design
Randomized · Quadruple · Treatment
Enrollment
129actual
Sites
28
Countries
Canada, Germany, Japan +3
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2024-12-03 | actual | When the study began enrolling |
| Primary completion | 2026-07-10 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | Nov 2027 | estimated | The whole study's end, after follow-up |
| First posted | 2024-09-27 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-08-06 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Angelman Syndrome
Interventions
- Drug: GTX-102 — also filed as apazunersen
- Procedure: Sham-LP
Primary outcome
what the primary-completion date above is the date OFChange from Baseline in Bayley-4 Cognitive Raw Score Without Caregiver Input at Day 338
measured Baseline, Day 338
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