Condition (MeSH)
Angelman Syndrome
ClinicalTrials.gov lists 51 trials for Angelman Syndrome or a narrower condition beneath it. Ultragenyx Pharmaceutical Inc has the most among industry and government lead sponsors, with 4.
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Trials per phase (log scale)
51 of the 51 trials are tagged with Angelman Syndrome itself; the rest are tagged with a narrower condition beneath it.
When did Angelman Syndrome trials start? (20)
Shown in this order: most recent first, 1990 onwards. 2026 is partial: trials registered with a 2026 start date so far, not a full year.
Trials over time, by phase
- Phase 1
- Phase 1/2
- Phase 2
- Phase 2/3
- Phase 3
- Not applicable
- Observational
Top of scale: 6
Trials registered with a start date in each year, 1990 onward, stacked by phase (complete years only; the current partial year is in the table's notes). The table below lists the same counts, most recent years first.
| Year | Trials started |
|---|---|
| 2026 (partial year) | 3 |
| 2025 | 4 |
| 2024 | 3 |
| 2023 | 4 |
| 2022 | 2 |
| 2021 | 6 |
| 2020 | 2 |
| 2019 | 2 |
| 2018 | 5 |
| 2017 | 3 |
Showing 10 of 20 earlier years.
No forecast is made for this condition: it averages 3.8 trial starts a year over the five years to September, under the 5 a year the method needs.
Prediction, not a registry value: median of 36 months from start to primary completion across 7 trials still running at the 2026-10-09 snapshot; registered median of 27 months across 28 trials with a primary completion typed Actual. Source: ClinicalTrials.gov / AACT (CTTI), public domain.
What phase are Angelman Syndrome trials in? (8)
Shown in this order: phase order.
Show the trials by phase as a table
| Phase | Trials |
|---|---|
| Phase 1 | 6 |
| Phase 1/2 | 3 |
| Phase 2 | 6 |
| Phase 2/3 | 1 |
| Phase 3 | 7 |
| Not applicable | 6 |
| Observational | 21 |
| Expanded access | 1 |
How many Angelman Syndrome trials are recruiting? (8)
Shown in this order: the order a trial moves through, from not yet recruiting to unknown.
| Status | Trials |
|---|---|
| Recruiting | 10 |
| Enrolling by invitation | 1 |
| Active, not recruiting | 7 |
| Available | 1 |
| Completed | 26 |
Showing 5 of 8 statuses.
Status as registered on ClinicalTrials.gov. Each trial is counted once.
Which lead sponsors run the most Angelman Syndrome trials? (7)
Shown in this order: most trials first. Lead sponsors the registry classes as industry, NIH, US federal, other government or network. A hospital or university the registry files as government can appear here. Sponsors it classes as academic or other are shown on the full page, because that class cannot separate an institution from a named investigator.
| Sponsor | Trials |
|---|---|
| Ultragenyx Pharmaceutical Inc | 4 |
| Healx AI | 3 |
| Hoffmann-La Roche | 3 |
| Ionis Pharmaceuticals, Inc. | 3 |
| Neurim Pharmaceuticals Ltd. | 2 |
Showing 5 of 7 sponsors.
Which drugs are being tested for Angelman Syndrome? (3)
Shown in this order: most trials first. One row per drug, matched to a single molecule under all its names, ranked by number of trials.
| Drug | Trials |
|---|---|
| GTX-102 | 4 |
| obudanersen | 3 |
| Levodopa | 2 |
Interventions as named in the registry (12)
Shown in this order: most trials first.
| Drug | Trials |
|---|---|
| RO7248824 | 2 |
| Rugonersen | 2 |
| Melatonin PR | 2 |
| OV101 | 2 |
| Minocyclin | 2 |
Showing 5 of 12 interventions.
These are the names sponsors entered on ClinicalTrials.gov that we have not matched to a single molecule. Some are drugs under a brand or code name; others are procedures, doses or arm labels.
Which serious adverse events do Angelman Syndrome trials report? (10)
Shown in this order: most subjects affected first. Subjects affected summed across trials, a cross-trial signal, not a rate.
| Adverse event | Subjects affected | Trials |
|---|---|---|
| Seizure | 25 | 4 |
| Insomnia | 14 | 1 |
| Infection | 7 | 1 |
| SAE -Serious adverse event | 4 | 1 |
| SAE - Serious adverse event | 3 | 1 |
Showing 5 of 10 adverse events.
Which publications cover Angelman Syndrome? (47)
Shown in this order: major-topic papers first, then newest, then most linked to trials.
| Publication | Journal | Year | Major topic |
|---|---|---|---|
| The UBE3A-ATS antisense oligonucleotide rugonersen in children with Angelman syndrome: a phase 1 trial. | Nature medicine | 2025 | Yes |
| An ASO therapy for Angelman syndrome that targets an evolutionarily conserved region at the start of the <i>UBE3A-AS</i> transcript. | Science translational medicine | 2023 | Yes |
| H4C5 missense variant leads to a neurodevelopmental phenotype overlapping with Angelman syndrome. | American journal of medical genetics. Part A | 2023 | Yes |
| Gaboxadol in angelman syndrome: A double-blind, parallel-group, randomized placebo-controlled phase 3 study. | European journal of paediatric neurology : EJPN : official journal of the European Paediatric Neurology Society | 2023 | Yes |
| Does the registry speak your language? A case study of the Global Angelman Syndrome Registry. | Orphanet journal of rare diseases | 2023 | Yes |
Showing 5 of 47 publications.
Prevalence (36)
Shown in this order: jurisdiction, then disease name. Orphanet observation for the mapped ORPHA concept; the mapping relation column says whether that concept is exactly this condition or broader or narrower.
| Orphanet disease | Type | Class | Geography | Jurisdiction | Mapping relation |
|---|---|---|---|---|---|
| Angelman syndrome | Point prevalence | 1-9 / 100 000 | United Kingdom | GB | Unspecified |
| Angelman syndrome | Point prevalence | 1-9 / 100 000 | United Kingdom | GB | Exact |
| Angelman syndrome | Point prevalence | 1-9 / 100 000 | United Kingdom | GB | Exact |
| Angelman syndrome | Prevalence at birth | 1-9 / 1 000 000 | Denmark | Not stated | Exact |
| Angelman syndrome | Point prevalence | 1-9 / 100 000 | Worldwide | Not stated | Unspecified |
Showing 5 of 36 prevalence observations.
Rare-disease identity (2)
Shown in this order: exact, broader, narrower, other.
| Orphanet disease | ORPHA code | Relation | Source |
|---|---|---|---|
| Angelman syndrome | 72 | Exact | Orphanet Rare Disease Ontology (ORDO) |
| Angelman syndrome | 72 | Exact | Orphadata Science knowledge files, Product 1 |
Not on this page
Not measured: delivery record.
Checked, with nothing recorded for this condition: sub-conditions in mesh.