A Safety and Efficacy Study of GTX-102 in Subjects With Deletion- or Nondeletion-type Angelman Syndrome (AS)
← catalyst calendarNCT07157254 · readout ≤ 1,261 d
Sponsored by Ultragenyx Pharmaceutical Inc (industry) · RARE — their whole pipeline →.
Phase
Phase 2
Status
Recruiting
Study type
Interventional
Design
Randomized · None · Treatment
Enrollment
60estimated
Sites
21
Countries
Argentina, Brazil, France +5
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 | 2025-10-13 | actual | When the study began enrolling |
| Primary completion | Jan 2030 | estimated | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | Jan 2030 | estimated | The whole study's end, after follow-up |
| First posted | 2025-09-05 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-08-07 | 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
- Other: No intervention
- Drug: GTX-102 — also filed as apazunersen
Primary outcomes
what the primary-completion date above is the date OFSubprotocol A/B/C/D: Number of Participants with Treatment Emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs), Severe Events, and Events Related to Investigational Product, Procedure, and Premedication
measured Up to Day 506
Subprotocol A Only: Bayley-4 Cognitive Without Caregiver Input Raw Score Change from Baseline at Day 338
measured Baseline, Day 338
Subprotocol B/D Only: Multidomain Responder Index (MDRI) Net Response at Day 338
measured Baseline, Day 338
Subprotocol C Only: MDRI Net Response at Day 338
measured Baseline, Day 338
Permalink · RARE's whole pipeline · Catalyst calendar · Every registered study · What changed