Angelman SyndromePhase 3NCT06914609
REVEAL: A Phase 3 Study of Obudanersen (ION582) in Angelman Syndrome
A Phase 3 study testing obudanersen in people with Angelman Syndrome, run by Ionis Pharmaceuticals, Inc. at 41 sites in 12 countries.
Trial summary
The purpose of this study is to evaluate the efficacy and safety of obudanersen in children and adults with Angelman syndrome caused by a deletion or mutation of the UBE3A gene. Read more about this study
- Who is it for?
- Ages 2 to 50 years
- Conditions the study is for
- Angelman Syndrome
- What is being tested?
- obudanersen
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 156 participants
- Where
- 41 sitesin 12 countries
- Study dates
- 10 Jun 2025to Apr 2030
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 2 to 50 years
- All sexes
- No healthy volunteers
- Child, Adult
Who may be able to join
- The participants caregiver(s)/ legally authorized representative must have given written informed consent and any authorizations required by local law and be able to comply with all study requirements.
- Medically stable and can undergo sedation and/or general anesthesia without intubation.
- 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.
- Participant has a clinical diagnosis of Angelman syndrome (AS) with molecular confirmation of either Ubiquitin-protein ligase E3A (UBE3A) deletion or UBE3A mutation.
- 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.
- 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.
Who cannot join
- Must not have any clinically significant abnormalities in medical history (e.g., major surgery within 3 months of screening), or on physical examination for which treatment with an antisense oligonucleotide (ASO) would be contraindicated or which, in the opinion of the Principal Investigator (PI), could confound the results of this study.
- 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.
- 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.
- 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.
- 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.
- Has molecular confirmation of AS due to paternal uniparental disomy, imprinting center defect, or mosaic findings.
- Other inclusion/exclusion criteria may apply.
Trial locations and contacts
41 sites in 12 countries.
41 sites in 12 countries
United States18 sites
Children's Healthcare of Atlanta
Atlanta, Georgia, 30329
Colorado Children's Hospital Research Institute
Aurora, Colorado, 80045
Boston Children's Hospital
Boston, Massachusetts, 02115
University of North Carolina at Chapel Hill School of Medicine
Carrboro, North Carolina, 27510
Rush University Medical Center
Chicago, Illinois, 60612
Cincinnati Children's Hospital
Cincinnati, Ohio, 45229
Nationwide Children's Hospital
Columbus, Ohio, 43205
Texas Children's Hospital
Houston, Texas, 77030
Children's Mercy
Kansas City, Missouri, 64108
Cedars-Sinai Medical Center
Los Angeles, California, 90048
UCLA Clinical & Translational Research Center (CTRC)
Los Angeles, California, 90095
Nicklaus Children's Hospital
Miami, Florida, 33155
Vanderbilt Clinical Research Center
Nashville, Tennessee, 37232
Ichan School of Medicine at Mount Sinai
New York, New York, 10029
Columbia University Irving Medical Center
New York, New York, 10032
Children's Hospital of Philadelphia
Philadelphia, Pennsylvania, 19104
Rady Children's Hospital
San Diego, California, 92123
Children's National Hospital
Washington D.C., District of Columbia, 20011
Australia4 sites
Austin Hospital
Heidelberg, 3084
Perth Children's Hospital
Nedlands, 6009
Sydney Children's Hospital
Randwick, 2031
Queensland Children's Hospital
South Brisbane, Queensland, 4101
Canada4 sites
University of Alberta Hospital
Edmonton, T6G 2B7
London Health Science Centre - Children's Hospital
London, Ontario, N6A 5W9
McGill University Health Centre
Montreal, Quebec, H4A 3J1
British Columbia Children's Hospital
Vancouver, V6H 3V4
Italy3 sites
Fondazione IRCCS Istituto Neurologico Carlo Besta
Milan, 20133
Azienda Ospedaliero Universitaria Pisana
Pisa, 56126
Ospedale Pediatrico Bambino Gesù
Roma, 00165
Japan2 sites
Osaka Women's and Children's Hospital
Izumi, Osaka, 594-1101
National Center of Neurology and Psychiatry
Kodaira, Tokyo, 187-8551
South Korea2 sites
Seoul National University Hospital
Seoul, 03080
Samsung Medical Center
Seoul, 06351
Spain2 sites
Hospital Sant Joan de Deu
Barcelona, 08950
Corporacio Sanitaria Parc Tauli - Hospital de Sabadell
Sabadell, 08208
United Kingdom2 sites
Great Ormond Street Hospital for Children - NHS Foundation Trust
London, WC1N 3JH
John Radcliffe Hospital
Oxford, OX3 9DU
Germany1 site
Klinikum der Ludwig-Maximilians-Universitaet Muenchen
München, 81377
About this study
Official title: Phase 3 Study of the Efficacy and Safety of ION582 in Children and Adults With Angelman Syndrome
The purpose of this study is to evaluate the efficacy and safety of obudanersen in children and adults with Angelman syndrome caused by a deletion or mutation of the UBE3A gene.
Read the detailed description
This is a Phase 3, randomized, double-blind, placebo-controlled study in people with Angelman syndrome. The study will consist of 4 periods: a screening period of up to 28 days, an approximate 60-week double blind, placebo-controlled treatment period, followed by an approximate 25-month Long-Term Extension (LTE) treatment period, and an approximate 8-month Post-LTE follow-up period. The study will be comprised of 2 cohorts. Cohort 1 will include pediatric participants, aged 2 to less than (<)18 years old and serve as the population for evaluation of primary and secondary outcome measures; Cohort 2 will include adult participants, aged 18 to ≤50 years old. Participants will be randomized 1:1 to 80 mg obudanersen or placebo during the double-blind placebo-controlled treatment period. Participants from both cohorts completing the placebo-controlled treatment period will be eligible to transition into the LTE Treatment Period wherein all trial participants will receive obudanersen. Participant, Caregiver, Investigator and Sponsor will remain blinded to the obudanersen dose administered to participants during the LTE.
The study initiated in 2024 with three dosing groups (40 mg obudanersen, 80 mg obudanersen, and placebo). Following additional review of data from the ongoing Phase 1/2 trial of obudanersen (HALOS), REVEAL was amended in December 2025 to its current form as a two-arm study: 80 mg obudanersen and placebo. Following the amendment, participants who were randomized to receive 40 mg obudanersen will be transitioned to receive 80 mg obudanersen.
- Conditions
- Angelman Syndrome
- Being tested
- obudanersen, Placebo
- Keywords
- ION582, Angelman Syndrome
- Medical subject headings
- Angelman Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
obudanersenDrug
Also called ION582
obudanersen will be administered by IT injection.
PlaceboDrug
obudanersen matching placebo will be administered by IT injection.
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1 obudanersen 80 mg | Experimental | Participants (aged 2 to <18 years old) will be administered obudanersen 80 mg via intrathecal (IT) injection every 12 weeks during the double blind and LTE treatment periods. Receives: Drug: obudanersen |
| Cohort 1 Placebo | Placebo comparator | Participants (aged 2 to <18 years old) will be administered obudanersen matching placebo via IT injection every 12 weeks during the double-blind treatment period and then administered obudanersen 40 mg or 80 mg every 12 weeks during the LTE treatment period. Receives: Drug: Placebo |
| Cohort 2 obudanersen 80 mg | Experimental | Participants (aged 18 to ≤50 years old) will be administered obudanersen 80 mg via IT injection every 12 weeks during the double blind and LTE treatment periods. Receives: Drug: obudanersen |
| Cohort 2 Placebo | Placebo comparator | Participants (aged 18 to ≤50 years old) will be administered obudanersen matching placebo via IT injection every 12 weeks during the double-blind treatment period and then randomized to obudanersen 40 mg or 80 mg every 12 weeks during the LTE treatment period. Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Performance on the Expressive Communication Subdomain Raw Score of the Bayley Scales for Infant and Toddler Development-4 (Bayley-4) Without Caregiver Input in Cohort 1
The Bayley-4 is a performance-based assessment of developmental functioning across communication, cognition, and motor skills. The expressive communication subdomain of communication measures preverbal and verbal communication. The total raw score reflects the sum of all the item scores within the expressive communication subdomain, with higher scores reflecting greater expressive communication ability.
Measured: Baseline and Week 52
Secondary outcomes (9)
Change in Bayley Scales for Infant and Toddler Development-4 (Bayley-4): Cognition Subdomain Raw Score Without Caregiver Input
The Bayley-4 is a performance-based assessment of developmental functioning across communication, cognition, and motor skills. The cognitive subdomain measures learning, memory and concept formation. The total raw score reflects the sum of all the item scores within the expressive communication subdomain, with higher scores reflecting greater cognitive ability.
Measured: Baseline and Week 52
Change in Symptoms of Angelman Syndrome -Clinician Global Impression of Change (SAS-CGI-C): Overall AS
The SAS-CGI-C for Overall AS is a disease-specific clinician-reported outcome assessment measure for Angelman syndrome. The clinicians rate their overall impression of the change of the participant's Angelman syndrome symptoms utilizing a 7-point scale, ranging from "very much improved" (1) to "very much worse" (7).
Measured: Baseline and Week 52
Change in Vineland Adaptive Behavior Scale-3 (Vineland-3): Receptive Communication Subdomain Raw Score
The Vineland-3 assesses adaptive behaviors across 4 domains via a semi-structured interview between a trained clinician and the caregiver of the participant with AS. The receptive communication subdomain of communication measures the participant's ability to attend, understand, and respond appropriately to information from others. The total raw score reflects the sum of all the item scores within the receptive communication subdomain, with higher scores reflecting greater receptive communication ability.
Measured: Baseline and Week 52
Change in Vineland Adaptive Behavior Scale-3 (Vineland-3): Daily Living Skills, Personal Subdomain Raw Score
The Vineland-3 assesses adaptive behaviors across 4 domains via a semi-structured interview between a trained clinician and the caregiver of the participant with AS. The Personal subdomain of the Daily Living Skills domain measures the participant's self-sufficiency in such areas as eating, dressing, washing, hygiene, and health care. The total raw score reflects the sum of all the item scores within the Personal subdomain, with higher scores reflecting greater ability.
Measured: Baseline and Week 52
Change in Symptoms of Angelman Syndrome - Clinician Global Impression of Change (SAS-CGI-C): Sleep Problems
The SAS-CGI-C for Sleep Problems is a disease-specific clinician-reported outcome assessment measure for Angelman syndrome. The clinicians rate their overall impression of the change in the participant's sleep problems utilizing a 7-point scale, ranging from "very much improved" (1) to "very much worse" (7).
Measured: Baseline and Week 52
Change in Bayley Scales for Infant and Toddler Development-4 (Bayley-4): Fine Motor Subdomain Raw Score Without Caregiver Input
The Bayley-4 is a performance-based assessment of developmental functioning across communication, cognition, and motor skills. The Fine Motor subdomain of communication measures motor abilities such as reaching, object manipulation, and grasping. The total raw score reflects the sum of all the item scores within the fine motor subdomain, with higher scores reflecting greater fine motor ability.
Measured: Baseline to Week 52
Change in Observer-Reported Communication Ability (ORCA): Overall Emerging T Score
The ORCA measure assesses, from the caregiver's perspective, the communication ability of individuals with neurodevelopmental disorders, like Angelman syndrome. This questionnaire assesses expressive, receptive, and pragmatic communication. The ORCA measure produces a single score that is an estimate of an individual's overall level of communication ability, with higher T-scores reflecting greater communication ability.
Measured: Baseline and Week 52
Percentage of Participants with Treatment-emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs)
Measured: Up to Week 52
Change in Vital Signs and Clinical Laboratory Results
Measured: Baseline and Week 52
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Apr 2025
- Study start10 Jun 2025
- Primary completionAug 2027 (estimated)
- Study completionApr 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Angelman SyndromeStudies of the same condition, open and under way.
- More trials run by Ionis Pharmaceuticals, Inc.The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 156 participants (actual)
Sponsor and investigators
- Lead sponsor
- Ionis Pharmaceuticals, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06914609
- Sponsor's protocol ID
- ION582-CS2
- Other IDs
- 2024-519711-33-00, U1111-1319-2765
- Status last verified
- Sep 2026
- First submitted
- 22 Mar 2025
- Last updated
- 29 Sep 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Ionis may share anonymized individual participant data, aggregated clinical data, and other types of data that support the results in this study. Data requests from qualified researchers will be considered once all three of the following criteria are met: (1) 12 months from marketing approval of the study drug in both the United States and European Union; (2) 18 months from conclusion of the study; and (3) 6 months from publication of study article. Access would be via a secure environment and is contingent upon approval of a research proposal and entry into an appropriate data use agreement. Requests to access data can be submitted via the website https://vivli.org/ourmember/ionis/.
Study at a glance
From the registry record, last updated by the sponsor on 29 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phase 3 Study of the Efficacy and Safety of ION582 in Children and Adults With Angelman Syndrome
- ClinicalTrials.gov ID
- NCT06914609
- Acronym / sponsor ID
- ION582-CS2
- Conditions
- Angelman Syndrome
- Keywords
- ION582, Angelman Syndrome
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 156 participants (actual)
- Lead sponsor
- Ionis Pharmaceuticals, Inc.Industry (pharma, biotech, devices)
- Study start
- 10 Jun 2025 (actual)
- Primary completion
- Aug 2027 (estimated)
- Study completion
- Apr 2030 (estimated)
- First posted
- 6 Apr 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to evaluate the efficacy and safety of obudanersen in children and adults with Angelman syndrome caused by a deletion or mutation of the UBE3A gene.
Detailed description
This is a Phase 3, randomized, double-blind, placebo-controlled study in people with Angelman syndrome. The study will consist of 4 periods: a screening period of up to 28 days, an approximate 60-week double blind, placebo-controlled treatment period, followed by an approximate 25-month Long-Term Extension (LTE) treatment period, and an approximate 8-month Post-LTE follow-up period. The study will be comprised of 2 cohorts. Cohort 1 will include pediatric participants, aged 2 to less than (<)18 years old and serve as the population for evaluation of primary and secondary outcome measures; Cohort 2 will include adult participants, aged 18 to ≤50 years old. Participants will be randomized 1:1 to 80 mg obudanersen or placebo during the double-blind placebo-controlled treatment period. Participants from both cohorts completing the placebo-controlled treatment period will be eligible to transition into the LTE Treatment Period wherein all trial participants will receive obudanersen. Participant, Caregiver, Investigator and Sponsor will remain blinded to the obudanersen dose administered to participants during the LTE.
The study initiated in 2024 with three dosing groups (40 mg obudanersen, 80 mg obudanersen, and placebo). Following additional review of data from the ongoing Phase 1/2 trial of obudanersen (HALOS), REVEAL was amended in December 2025 to its current form as a two-arm study: 80 mg obudanersen and placebo. Following the amendment, participants who were randomized to receive 40 mg obudanersen will be transitioned to receive 80 mg obudanersen.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Cohort 1 obudanersen 80 mg | Experimental | Drug: obudanersenParticipants (aged 2 to <18 years old) will be administered obudanersen 80 mg via intrathecal (IT) injection every 12 weeks during the double blind and LTE treatment periods. |
| Cohort 1 Placebo | Placebo comparator | Drug: PlaceboParticipants (aged 2 to <18 years old) will be administered obudanersen matching placebo via IT injection every 12 weeks during the double-blind treatment period and then administered obudanersen 40 mg or 80 mg every 12 weeks during the LTE treatment period. |
| Cohort 2 obudanersen 80 mg | Experimental | Drug: obudanersenParticipants (aged 18 to ≤50 years old) will be administered obudanersen 80 mg via IT injection every 12 weeks during the double blind and LTE treatment periods. |
| Cohort 2 Placebo | Placebo comparator | Drug: PlaceboParticipants (aged 18 to ≤50 years old) will be administered obudanersen matching placebo via IT injection every 12 weeks during the double-blind treatment period and then randomized to obudanersen 40 mg or 80 mg every 12 weeks during the LTE treatment period. |
Who may qualify
- Ages
- 2 to 50 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (6 listed)
- The participants caregiver(s)/ legally authorized representative must have given written informed consent and any authorizations required by local law and be able to comply with all study requirements.
- Medically stable and can undergo sedation and/or general anesthesia without intubation.
- 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.
- Participant has a clinical diagnosis of Angelman syndrome (AS) with molecular confirmation of either Ubiquitin-protein ligase E3A (UBE3A) deletion or UBE3A mutation.
- 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.
Key exclusion criteria (7 listed)
- Must not have any clinically significant abnormalities in medical history (e.g., major surgery within 3 months of screening), or on physical examination for which treatment with an antisense oligonucleotide (ASO) would be contraindicated or which, in the opinion of the Principal Investigator (PI), could confound the results of this study.
- 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.
- 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.
- 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.
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| obudanersenAlso: ION582obudanersen will be administered by IT injection. | Drug | Cohort 1 obudanersen 80 mg, Cohort 2 obudanersen 80 mg |
| Placeboobudanersen matching placebo will be administered by IT injection. | Drug | Cohort 1 Placebo, Cohort 2 Placebo |
Primary outcome
Change in Performance on the Expressive Communication Subdomain Raw Score of the Bayley Scales for Infant and Toddler Development-4 (Bayley-4) Without Caregiver Input in Cohort 1
Time frame: Baseline and Week 52
The Bayley-4 is a performance-based assessment of developmental functioning across communication, cognition, and motor skills. The expressive communication subdomain of communication measures preverbal and verbal communication. The total raw score reflects the sum of all the item scores within the expressive communication subdomain, with higher scores reflecting greater expressive communication ability.
9 secondary outcomes
Change in Bayley Scales for Infant and Toddler Development-4 (Bayley-4): Cognition Subdomain Raw Score Without Caregiver Input
Time frame: Baseline and Week 52
Change in Symptoms of Angelman Syndrome -Clinician Global Impression of Change (SAS-CGI-C): Overall AS
Time frame: Baseline and Week 52
Change in Vineland Adaptive Behavior Scale-3 (Vineland-3): Receptive Communication Subdomain Raw Score
Time frame: Baseline and Week 52
Change in Vineland Adaptive Behavior Scale-3 (Vineland-3): Daily Living Skills, Personal Subdomain Raw Score
Time frame: Baseline and Week 52
Change in Symptoms of Angelman Syndrome - Clinician Global Impression of Change (SAS-CGI-C): Sleep Problems
Time frame: Baseline and Week 52
Change in Bayley Scales for Infant and Toddler Development-4 (Bayley-4): Fine Motor Subdomain Raw Score Without Caregiver Input
Time frame: Baseline to Week 52
Change in Observer-Reported Communication Ability (ORCA): Overall Emerging T Score
Time frame: Baseline and Week 52
Percentage of Participants with Treatment-emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs)
Time frame: Up to Week 52
Change in Vital Signs and Clinical Laboratory Results
Time frame: Baseline and Week 52
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Sep 2026.
- Individual participant dataSharing planned: Yes. Ionis may share anonymized individual participant data, aggregated clinical data, and other types of data that support the results in this study. Data requests from qualified researchers will be considered once all three of the following criteria are met: (1) 12 months from marketing approval of the study drug in both the United States and European Union; (2) 18 months from conclusion of the study; and (3) 6 months from publication of study article. Access would be via a secure environment and is contingent upon approval of a research proposal and entry into an appropriate data use agreement. Requests to access data can be submitted via the website https://vivli.org/ourmember/ionis/.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
41 sites in 12 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing obudanersen in people with Angelman Syndrome, run by Ionis Pharmaceuticals, Inc. at 41 sites in 12 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 29 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 41 sites in United States, Australia, Canada, Italy, Japan and 7 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Performance on the Expressive Communication Subdomain Raw Score of the Bayley Scales for Infant and Toddler Development-4 (Bayley-4) Without Caregiver Input in Cohort 1 (time frame: Baseline and Week 52). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Sep 2026.