Actively Recruiting
A Phase 2, Open-label, Basket Study Investigating the Safety and Efficacy of GTX-102 in Adult and Pediatric Subjects With Deletion- or Nondeletion-type Angelman Syndrome
Led by Ultragenyx Pharmaceutical Inc · Updated on 2026-06-05
60
Participants Needed
21
Research Sites
N/A
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating the safety and effectiveness of GTX-102 in individuals with Angelman syndrome, a genetic condition. This study includes participants of different ages and genetic types of Angelman syndrome. It is a phase 2, open-label basket study with several subprotocols designed to assess the treatment across various groups and age ranges, sponsored by Ultragenyx Pharmaceutical Inc. Participants receive GTX-102, an antisense oligonucleotide, administered through intrathecal (spinal) injections. Dosing starts with increasing amounts until the target dose is reached, followed by maintenance doses every three months. The study includes subprotocols A, B, C, and D; some groups receive treatment directly, while one group initially receives no treatment before starting GTX-102. After completing the study, participants may continue treatment in a long-term extension. During the study, participants undergo screening, treatment, and follow-up visits with assessments including cognitive, communication, motor skills, behavior, and sleep evaluations. Safety is closely monitored by tracking adverse events and lab tests. Measurements are taken at baseline and after about 11 months. The study lasts until 2030, with ongoing evaluation of participant response and safety throughout the treatment and follow-up periods.
CONDITIONS
Brief Title
A Safety and Efficacy Study of GTX-102 in Subjects With Deletion- or Nondeletion-type Angelman Syndrome (AS)
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Signed informed consent from parent(s) or legal guardian(s)
- Males and females aged 1 to less than 4 years with deletion-type Angelman syndrome
- Males and females aged 4 to less than 18 years with UPD/ICD Angelman syndrome
- Males and females aged 18 to less than 65 years with any genotype of Angelman syndrome
- Males and females aged 4 to less than 18 years with mutation-type Angelman syndrome
- Weight of at least 8 kg at screening
- Platelet count and blood clotting tests within specified normal limits at screening
- Willingness and ability to comply with all study visits, drug administration, tests, lumbar puncture, MRI, and anesthesia without intubation
- Females of childbearing potential who are sexually active must use effective contraception or abstinence from consent until 6 months after last dose; males must use contraception or abstain from heterosexual intercourse during study and for 3 months after last dose
You will not qualify if you...
- Recent changes (within 1 month) in medications or diets intended to treat Angelman syndrome symptoms, excluding weight-based adjustments
- Conditions increasing risk of unsuccessful lumbar puncture
- Current or expected use of drugs that increase bleeding risk
- Known allergy or hypersensitivity to GTX-102 or its components
- Any condition, lab abnormality, or infection that may interfere with study participation or safety
- Pregnancy, breastfeeding, or plans to become pregnant during the study
- Use of investigational products or gene therapies within 6 months prior to screening
- Participation in another interventional study concurrently
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - Duration until target dose is achieved
Participants receive increasing doses of GTX-102 via intrathecal injection until the target dose is achieved. Participants in the no treatment group do not receive the study drug during this initial period.
Visits every 3 months during dose escalation
Duration - Ongoing throughout the study after loading
After reaching the target dose, participants receive GTX-102 doses every 3 months to maintain treatment.
Dosing visits every 3 months (Q3M)
Duration - Up to Day 506 (approximately 17 months)
Participants are monitored for safety and efficacy outcomes after dosing periods.
Multiple visits for assessments up to Day 506
Trial Site Locations
Total: 21 locations
1
Cedars Sinai Medical Center
Los Angeles, California, United States, 90048
Actively Recruiting
2
Rush University Medical Center
Chicago, Illinois, United States, 60612
Actively Recruiting
3
Clinical Trial Site
Baltimore, Maryland, United States, 21205
Not Yet Recruiting
4
Clinical Trial Site
Kansas City, Missouri, United States, 64108
Not Yet Recruiting
5
Rare Disease Research
Hillsborough, North Carolina, United States, 27278
Actively Recruiting
6
Akron Children's Hospital
Akron, Ohio, United States, 44308
Actively Recruiting
7
UT Health Austin
Austin, Texas, United States, 78723
Actively Recruiting
8
Carum Research Inc.
Dallas, Texas, United States, 75243
Actively Recruiting
9
Hospital Universitario Austral
Pilar, Buenos Aires, Argentina
Actively Recruiting
10
Clinical Trial Site
Curitiba, Paraná, Brazil
Not Yet Recruiting
11
Clinical Trial Site
Santa Cecília, Porto Alegre, Brazil
Not Yet Recruiting
12
Clinical Trial Site
Marseille, France
Not Yet Recruiting
13
Necker-Enfants Malades Hospital
Paris, France
Actively Recruiting
14
Sheba Medical Center
Ramat Gan, Israel
Actively Recruiting
15
Azienda Ospedaliera Universitaria Meyer IRCCS
Florence, Italy
Actively Recruiting
16
Fondazione IRCCS Istituto Neurologico C. Besta
Milan, Italy
Actively Recruiting
17
Clinical Trial Site
Rome, Italy
Not Yet Recruiting
18
Hospital de Santa Maria
Lisbon, Portugal
Actively Recruiting
19
Hospital Santa Joao
Porto, Portugal
Actively Recruiting
20
Clinical Trial Site
London, United Kingdom
Not Yet Recruiting
21
University of Oxford
Oxford, United Kingdom
Actively Recruiting
Research Team
P
Patients Contact Trial Recruitment
H
HCPs Contact: Medical Information
How is the study designed?
Study Type
INTERVENTIONAL
Masking
NONE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
TREATMENT
Number of Arms
5
Similar Trials
Frequently Asked Questions
Have more questions? Get in touch with our team for quick support
Not the Right Trial for You?
Explore thousands of other clinical trials that might be a better match.
Sign up to get personalized trial recommendations delivered to your inbox.
Already have an account? Log in here