Williams SyndromePhase 2NCT06087757
Clemastine Treatment in Individuals With Williams Syndrome
A Phase 2 study testing Open Label Clemastine with a blinded randomize withdrawal in people with Williams Syndrome, run by Sheba Medical Center at 2 sites in Israel.
Trial summary
This study explores the neurobiological etiology of Williams syndrome and potential therapeutic targets for associated social, motor, and cognitive abnormalities. The main translational objective will be to test the effectiveness of Clemasntine on neurocognitive and other associated abnormalities in individuals with… Read more about this study
- Who is it for?
- Ages 6 to 30 years
- Conditions the study is for
- Williams Syndrome
- What is being tested?
- Open Label Clemastine with a blinded randomize withdrawal
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 2 sitesIsrael
- Study dates
- 1 Apr 2024to Jul 2026
- Phase
- Phase 2
- 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 6 to 30 years
- All sexes
- No healthy volunteers
- Child, Adult
Who may be able to join
- Individuals with Williams syndrome, which has been confirmed by genetic testing.
- Ages 6-30.
- Normal values in safety variables (e.g. Normal ECG 120-129/80-84).
- No change in psychotropic medications and dosage during the last 4 weeks.
- During the study, no pharmacological change that may impact the study (e.g. ADHD
- medications).
Who cannot join
- Individuals with another genetic disorder besides Williams syndrome.
- Individuals with Williams syndrome, younger than 6 or older than 30 years old.
- Significant change in normal values in safety variables (e.g. high or low ECG).
- Change in medications and dosage during the last 4 weeks prior the beginning and
- during the study.
- Pregnancy.
- Using addictive substances such as alcohol.
Trial locations and contacts
2 sites in 1 country.
Israel2 sites
Child and Adolescent Psychiatry Unit, Sheba Medical Center
Ramat Gan
Tel Aviv University
Tel Aviv
About this study
Official title: Clemastine Treatment in Individuals With Williams Syndrome- a Double-blind Placebo Control to Assess the Safety and Efficacy
This study explores the neurobiological etiology of Williams syndrome and potential therapeutic targets for associated social, motor, and cognitive abnormalities. The main translational objective will be to test the effectiveness of Clemasntine on neurocognitive and other associated abnormalities in individuals with Williams syndrome.
Read the detailed description
The overarching aim of the research proposed is to examine the safty of Clemastine use for individuals with Williams syndrome. Further, we wish to examine the relationship between Clemastine treatment and cognitive, motor and behavioral deficits in individuals with Williams syndrome. This study is an open-label study with a blinded randomize withdrawal. Each participant will go through a baseline evaluation (see study outcomes) and will be treated with the FDA approved drug Clemastine, in an age dependent dose (dosage table below). After a substantial improvement will be noticed, the participants will be divided into 2 groups, in a randomized, double-blind, placebo-control study design.
- Conditions
- Williams Syndrome
- Being tested
- Open Label Clemastine with a blinded randomize withdrawal
- Keywords
- Clemastine, Cognition, Myelination abnormalities
- Medical subject headings
- Williams Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Open Label Clemastine with a blinded randomize withdrawalDrug
Clemastine will be given in doses as the maximum dose recommended for allergy condition. Age 6-12 years 4.02 mg/day, age 12-30 years 8.04 mg/day.
| Study group | Role | What they receive |
|---|---|---|
| Open Label | Experimental | Not described Receives: Drug: Open Label Clemastine with a blinded randomize withdrawal |
| Blinded randomize withdrawal | Experimental | Not described Receives: Drug: Open Label Clemastine with a blinded randomize withdrawal |
What is being measured
The primary outcome is the main question the study is designed to answer.
Neurocognitive measures
Wechsler Intelligence Scale: The standard age-appropriate Wechsler scale. Wechsler Intelligence Scale for Children, 4th edition(Wechsler 1991, Wechsler 2003) for subjects 17 years and younger and the Wechsler Adult Intelligence Scale, 3rd edition (WAIS III)(Wechsler 1997) for subjects older than 17 years.
NIH ToolBox (NIHTB): the NIHTB is a computerized neurocognitive battery developed by NIH that was designed to include measures of cognitive flexibility and inhibitory control, as well as a measure of working memory. http://www.healthmeasures.net/explore-measurement-systems/nih-toolbox/
Measured: December 2024
Secondary outcomes (1)
Motor and Neurological assessment. Motor and Neurological assessment. Motor and Neurological assessment. Motor and neurolocgial measures
The Beery-Buktenica Developmental Test of Visual-Motor Integration
GAITRite walkway: GAITRite is a sensitive walkway measuring temporal and spatial parameters.
Psychiatric evaluation: a semi-structured interview for neuropsychiatric diagnoses with the Schedule for Affective Disorders and Schizophrenia for School-Aged Children.
The Child Behavior Checklist: measures behavioral/emotional problems and competencies.
Attention Deficit Hyperactivity Disorder Rating Scale.
The Screen for Child Anxiety-Related Emotional Disorders.
The Social Responsiveness Scale-Second Edition.
Adaptive Behavior Assessment System-2nd Edition.
Measured: December 2024
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Oct 2023
- Study start1 Apr 2024
- Primary completionMay 2026 (estimated)
- Study completionJul 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Williams SyndromeStudies of the same condition, open and under way.
- More trials run by Sheba Medical CenterThe 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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Sheba Medical Center
- Sponsor type
- Other government
- Collaborators
- Tel Aviv University
- Responsible party
- Principal investigator, Prof. Doron Gothelf MD, Sheba Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06087757
- Sponsor's protocol ID
- 9011-21-SMC
- Status last verified
- Mar 2026
- First submitted
- 5 Oct 2023
- Last updated
- 6 Mar 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 6 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Clemastine Treatment in Individuals With Williams Syndrome- a Double-blind Placebo Control to Assess the Safety and Efficacy
- ClinicalTrials.gov ID
- NCT06087757
- Acronym / sponsor ID
- 9011-21-SMC
- Conditions
- Williams Syndrome
- Keywords
- Clemastine, Cognition, Myelination abnormalities
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Sheba Medical CenterOther government
- Collaborators
- Tel Aviv University
- Study start
- 1 Apr 2024 (actual)
- Primary completion
- May 2026 (estimated)
- Study completion
- Jul 2026 (estimated)
- First posted
- 18 Oct 2023 (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.
This study explores the neurobiological etiology of Williams syndrome and potential therapeutic targets for associated social, motor, and cognitive abnormalities. The main translational objective will be to test the effectiveness of Clemasntine on neurocognitive and other associated abnormalities in individuals with Williams syndrome.
Detailed description
The overarching aim of the research proposed is to examine the safty of Clemastine use for individuals with Williams syndrome. Further, we wish to examine the relationship between Clemastine treatment and cognitive, motor and behavioral deficits in individuals with Williams syndrome. This study is an open-label study with a blinded randomize withdrawal. Each participant will go through a baseline evaluation (see study outcomes) and will be treated with the FDA approved drug Clemastine, in an age dependent dose (dosage table below). After a substantial improvement will be noticed, the participants will be divided into 2 groups, in a randomized, double-blind, placebo-control study design.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Open Label | Experimental | Drug: Open Label Clemastine with a blinded randomize withdrawal |
| Blinded randomize withdrawal | Experimental | Drug: Open Label Clemastine with a blinded randomize withdrawal |
Who may qualify
- Ages
- 6 to 30 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (6 listed)
- Individuals with Williams syndrome, which has been confirmed by genetic testing.
- Ages 6-30.
- Normal values in safety variables (e.g. Normal ECG 120-129/80-84).
- No change in psychotropic medications and dosage during the last 4 weeks.
- During the study, no pharmacological change that may impact the study (e.g. ADHD
Key exclusion criteria (7 listed)
- Individuals with another genetic disorder besides Williams syndrome.
- Individuals with Williams syndrome, younger than 6 or older than 30 years old.
- Significant change in normal values in safety variables (e.g. high or low ECG).
- Change in medications and dosage during the last 4 weeks prior the beginning and
- during the study.
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 |
|---|---|---|
| Open Label Clemastine with a blinded randomize withdrawalClemastine will be given in doses as the maximum dose recommended for allergy condition. Age 6-12 years 4.02 mg/day, age 12-30 years 8.04 mg/day. | Drug | Blinded randomize withdrawal, Open Label |
Primary outcome
Neurocognitive measures
Time frame: December 2024
Wechsler Intelligence Scale: The standard age-appropriate Wechsler scale. Wechsler Intelligence Scale for Children, 4th edition(Wechsler 1991, Wechsler 2003) for subjects 17 years and younger and the Wechsler Adult Intelligence Scale, 3rd edition (WAIS III)(Wechsler 1997) for subjects older than 17 years. NIH ToolBox (NIHTB): the NIHTB is a computerized neurocognitive battery developed by NIH that was designed to include measures of cognitive flexibility and inhibitory control, as well as a measure of working memory. http://www.healthmeasures.net/explore-measurement-systems/nih-toolbox/
1 secondary outcome
Motor and Neurological assessment. Motor and Neurological assessment. Motor and Neurological assessment. Motor and neurolocgial measures
Time frame: December 2024
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 6 Mar 2026.
- Individual participant dataSharing planned: Undecided
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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.
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Open Label Clemastine with a blinded randomize withdrawal in people with Williams Syndrome, run by Sheba Medical Center at 2 sites in Israel.
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 6 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Israel. 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. 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 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
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?
Neurocognitive measures (time frame: December 2024). 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 6 Mar 2026.