Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
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RECRUITING
PHASE3
158 participants
INTERVENTIONAL
2025-06-10
2030-04-30
Brief Summary
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Detailed Description
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The study initiated in 2024 with three dosing groups (40 mg ION582, 80 mg ION582, and placebo). Following additional review of data from the ongoing Phase 1/2 trial of ION582 (HALOS), REVEAL was amended in December 2025 to its current form as a two-arm study: 80 mg ION582 and placebo. Following the amendment, participants who were randomized to receive 40 mg ION582 will be transitioned to receive 80 mg ION582.
Conditions
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Keywords
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Study Design
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RANDOMIZED
PARALLEL
TREATMENT
QUADRUPLE
Study Groups
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Cohort 1 ION582 80 mg
Participants (aged 2 to \<18 years old) will be administered ION582 80 mg via IT injection Q12W during the double blind and LTE treatment periods.
ION582
ION582 will be administered by IT injection.
Cohort 1 Placebo
Participants (aged 2 to \<18 years old) will be administered ION582 matching placebo via IT injection Q12W during the double-blind treatment period and then administered ION582 40 mg or 80 mg Q12W during the LTE treatment period.
Placebo
ION582 matching placebo will be administered by IT injection.
Cohort 2 ION582 80 mg
Participants (aged 18 to ≤50 years old) will be administered ION582 80 mg via IT injection Q12W during the double blind and LTE treatment periods.
ION582
ION582 will be administered by IT injection.
Cohort 2 Placebo
Participants (aged 18 to ≤50 years old) will be administered ION582 matching placebo via IT injection Q12W during the double-blind treatment period and then randomized to ION582 40 mg or 80 mg Q12W during the LTE treatment period.
Placebo
ION582 matching placebo will be administered by IT injection.
Interventions
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ION582
ION582 will be administered by IT injection.
Placebo
ION582 matching placebo will be administered by IT injection.
Eligibility Criteria
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Inclusion Criteria
2. Medically stable and can undergo sedation and/or general anesthesia without intubation.
3. Male or female between 2 and lesser than or equal to (≤)50 years of age, depending on specific cohort, at the time of the in-clinic Screening visit.
4. Participant has a clinical diagnosis of Angelman syndrome (AS) with molecular confirmation of either Ubiquitin-protein ligase E3A (UBE3A) deletion or UBE3A mutation.
5. Currently receiving stable doses of concomitant medications typically prescribed for AS, such as anti-epileptic medication, behavioral management medications, sleep medications, gabapentin, cannabidiol, and special diets, supplements, or nutritional support for at least 8 weeks prior to the Baseline visit.
6. Legally authorized representative/caregiver(s) agree(s) not to post any of the participant's personal medical data or information related to the study on any website or social media site (e.g., Facebook, Instagram, X (formerly Twitter), YouTube, TikTok, etc.) from the time of enrollment until they are notified that the study is completed.
Exclusion Criteria
2. Known brain or spinal disease that would interfere with the lumbar puncture (LP) procedure, cerebrospinal fluid (CSF) circulation, or presence of other factors would affect the safety of the LP procedure.
3. Must not have any other conditions, which, in the opinion of the Investigator, would make the participant unsuitable for inclusion or could interfere with the participant participating in or completing the study.
4. Must not have any laboratory abnormalities or any other clinically significant abnormalities that would, as assessed by the Investigator, at screening or Baseline, render a participant unsuitable for inclusion.
5. Previous treatment with an oligonucleotide (including small interfering ribonucleic acid (RNA) \[siRNA\], ASOs) gene therapy or gene editing. This exclusion criterion does not apply to approved nucleic acid-based vaccines, including mRNA vaccines, which are allowed.
6. Has molecular confirmation of AS due to paternal uniparental disomy, imprinting center defect, or mosaic findings.
2 Years
50 Years
ALL
No
Sponsors
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Ionis Pharmaceuticals, Inc.
INDUSTRY
Responsible Party
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Locations
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Cedars-Sinai Medical Center
Los Angeles, California, United States
Rady Children's Hospital
San Diego, California, United States
Colorado Children's Hospital Research Institute
Aurora, Colorado, United States
Children's National Hospital
Washington D.C., District of Columbia, United States
Nicklaus Children's Hospital
Miami, Florida, United States
Rush University Medical Center
Chicago, Illinois, United States
Boston Children's Hospital
Boston, Massachusetts, United States
Children's Mercy
Kansas City, Missouri, United States
Ichan School of Medicine at Mount Sinai
New York, New York, United States
University of North Carolina at Chapel Hill School of Medicine
Carrboro, North Carolina, United States
Nationwide Children's Hospital
Columbus, Ohio, United States
Children's Hospital of Philadelphia
Philadelphia, Pennsylvania, United States
Sydney Children's Hospital
Randwick, , Australia
London Health Science Centre - Children's Hospital
London, Ontario, Canada
McGill University Health Centre
Montreal, Quebec, Canada
Osaka Women's and Children's Hospital
Izumi, Osaka, Japan
National Center of Neurology and Psychiatry
Kodaira, Tokyo, Japan
KK Women's and Children's Hospital
Singapore, , Singapore
Samsung Medical Center
Seoul, , South Korea
John Radcliffe Hospital
Oxford, , United Kingdom
Countries
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Central Contacts
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Other Identifiers
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2024-519711-33-00
Identifier Type: CTIS
Identifier Source: secondary_id
U1111-1319-2765
Identifier Type: OTHER
Identifier Source: secondary_id
ION582-CS2
Identifier Type: -
Identifier Source: org_study_id