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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/study/NCT06617429




Registration number
NCT06617429
Ethics application status
Date submitted
24/09/2024
Date registered
27/09/2024
Date last updated
22/06/2025

Titles & IDs
Public title
Phase 3 Efficacy and Safety Study of GTX-102 in Pediatric Subjects With AS
Scientific title
A Phase 3, Randomized, Double-blind, Sham-controlled Study Investigating the Efficacy and Safety of GTX-102 in Pediatric Subjects With Angelman Syndrome
Secondary ID [1] 0 0
2024-512600-19-00
Secondary ID [2] 0 0
GTX-102-CL301
Universal Trial Number (UTN)
Trial acronym
Aspire
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Angelman Syndrome 0 0
Condition category
Condition code
Human Genetics and Inherited Disorders 0 0 0 0
Other human genetics and inherited disorders
Neurological 0 0 0 0
Other neurological disorders
Other 0 0 0 0
Research that is not of generic health relevance and not applicable to specific health categories listed above

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Treatment: Drugs - GTX-102
Treatment: Surgery - Sham-LP

Experimental: GTX-102 - Participants will receive GTX-102 via lumbar puncture (LP) during both the double-blind and open-label period

Sham comparator: Sham-LP then GTX-102 - Participants will receive sham procedure during the double-blind period and then will receive GTX-102 via LP during the open-label period


Treatment: Drugs: GTX-102
antisense oligonucleotide

Treatment: Surgery: Sham-LP
Small needle prick on the lower back at the location where the LP injection is normally made
Intervention code [1] 0 0
Treatment: Drugs
Intervention code [2] 0 0
Treatment: Surgery
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Change from Baseline in Bayley-4 Cognitive Raw Score Without Caregiver Input at Day 338
Timepoint [1] 0 0
Baseline, Day 338
Secondary outcome [1] 0 0
Net Response in Multidomain Responder Index (MDRI)
Timepoint [1] 0 0
Day 338
Secondary outcome [2] 0 0
Change from Baseline in ABC-C Hyperactivity/Noncompliance Subscale Score at Day 338
Timepoint [2] 0 0
Baseline, Day 338
Secondary outcome [3] 0 0
Change from Baseline in Bayley-4 Receptive Communication Raw Score at Day 338
Timepoint [3] 0 0
Baseline, Day 338
Secondary outcome [4] 0 0
Change from Baseline in Angelman Severity Assessment (ASA) Sleep Rating Raw Score at Day 338
Timepoint [4] 0 0
Baseline, Day 338
Secondary outcome [5] 0 0
Change from Baseline in Vineland Adaptive Behavior Scales-3 (Vineland-3) Receptive Communication Raw Score at Day 338
Timepoint [5] 0 0
Baseline, Day 338
Secondary outcome [6] 0 0
Change from Baseline in Vineland-3 Expressive Communication Raw Score at Day 338
Timepoint [6] 0 0
Baseline, Day 338
Secondary outcome [7] 0 0
Change from Baseline in Bayley-4 Gross Motor Raw Score at Day 338
Timepoint [7] 0 0
Baseline, Day 338
Secondary outcome [8] 0 0
Change from Baseline in ASA Gross Motor Rating at Day 338
Timepoint [8] 0 0
Baseline, Day 338
Secondary outcome [9] 0 0
Number of Participants with Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs), Severity of AEs and Relationship to Investigational Drug, Procedure, and Premedication
Timepoint [9] 0 0
2 Years

Eligibility
Key inclusion criteria
Key

* Signed informed consent from parent(s) or legal guardian(s)
* Confirmed diagnosis of AS with genetic confirmation of full maternal ubiquitin-protein ligase E3A (UBE3A) gene deletion causing AS in the region of 15q11.2 q13
* Able to ambulate independently, or with assistance at the Screening Visit (note, a child whose primary means of mobility is by wheelchair is excluded from the study)
* Platelet count, prothrombin time / international normalized ratio, and partial thromboplastin time within 1.5x the normal limits at the Screening Visit
* Willing and able to comply with scheduled visits, drug administration plan, laboratory tests, and all study procedures, including LP procedure, MRI, and tolerating anesthesia without intubation
* From the time of informed consent through to at least 6 months after the final dose of GTX-102, females of childbearing potential who are sexually active must use highly effective contraception or abstinence. Males are able to participate if they agree to remain abstinent (refrain from heterosexual intercourse) or use acceptable contraceptive methods during the study and for at least 3 months after the final dose of GTX-102

Key
Minimum age
4 Years
Maximum age
17 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
* Any change in medications or diet/supplements intended to treat symptoms of AS (eg, sleeping aids, antiseizure medications, supplements, dietary change including ketogenic or low-glycemic index diet, other) within the month prior to the Screening Visit (excluding weight-based adjustments)
* Any condition that creates an increased risk of unsuccessful LP
* Current or expected concomitant use of drugs that increase the risk of bleeding (eg, heparin, low molecular weight heparin, platelet inhibitors)
* Known hypersensitivity to GTX-102 or its excipients that, in the judgment of the Investigator, places the subject at increased risk for adverse effects
* Presence or history of any condition, lab abnormality, or infection, that, in the judgement of the Investigator, would interfere with participation, pose undue safety risk, or would confound interpretation of results
* Pregnant or breastfeeding or planning to become pregnant (self or partner) at any time during the study
* Use of any investigational product or investigational medical device within 6 months or 5 half-lives prior to the Screening Visit or any prior use of gene therapy or ASO regardless of duration since last administration
* Concurrent participation in any interventional study

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Phase 3
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
3/12/2024
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
1/11/2027
Actual
Sample size
Target
120
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
Clinical Trial Site - South Brisbane
Recruitment hospital [2] 0 0
Clinical Trial Site - Sydney
Recruitment postcode(s) [1] 0 0
- South Brisbane
Recruitment postcode(s) [2] 0 0
- Sydney
Recruitment outside Australia
Country [1] 0 0
United States of America
State/province [1] 0 0
California
Country [2] 0 0
United States of America
State/province [2] 0 0
Colorado
Country [3] 0 0
United States of America
State/province [3] 0 0
Florida
Country [4] 0 0
United States of America
State/province [4] 0 0
Georgia
Country [5] 0 0
United States of America
State/province [5] 0 0
Illinois
Country [6] 0 0
United States of America
State/province [6] 0 0
Massachusetts
Country [7] 0 0
United States of America
State/province [7] 0 0
Missouri
Country [8] 0 0
United States of America
State/province [8] 0 0
New York
Country [9] 0 0
United States of America
State/province [9] 0 0
North Carolina
Country [10] 0 0
United States of America
State/province [10] 0 0
Texas
Country [11] 0 0
Canada
State/province [11] 0 0
Quebec
Country [12] 0 0
Canada
State/province [12] 0 0
Vancouver
Country [13] 0 0
Germany
State/province [13] 0 0
Hamburg
Country [14] 0 0
Germany
State/province [14] 0 0
Leipzig
Country [15] 0 0
Germany
State/province [15] 0 0
Munich
Country [16] 0 0
Japan
State/province [16] 0 0
Aichi
Country [17] 0 0
Japan
State/province [17] 0 0
Osaka
Country [18] 0 0
Japan
State/province [18] 0 0
Sapporo
Country [19] 0 0
Netherlands
State/province [19] 0 0
Rotterdam
Country [20] 0 0
Poland
State/province [20] 0 0
Gdansk
Country [21] 0 0
Poland
State/province [21] 0 0
Lódz
Country [22] 0 0
Spain
State/province [22] 0 0
Barcelona
Country [23] 0 0
Spain
State/province [23] 0 0
Madrid
Country [24] 0 0
Spain
State/province [24] 0 0
Seville

Funding & Sponsors
Primary sponsor type
Commercial sector/industry
Name
Ultragenyx Pharmaceutical Inc
Address
Country

Ethics approval
Ethics application status

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Medical Director
Address 0 0
Ultragenyx Pharmaceuticals Inc.
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Patients Contact: Trial Recruitment
Address 0 0
Country 0 0
Phone 0 0
1-888-756-8657
Fax 0 0
Email 0 0
[email protected]
Contact person for scientific queries

Data sharing statement


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

No documents have been uploaded by study researchers.

Results not provided in https://clinicaltrials.gov/study/NCT06617429