Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not recruitingRare disease

Study on the Effects and Safety of ZYN002 Gel for Children, Adolescents, and Young Adults with Fragile X Syndrome

Investigational
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying a hereditary condition known as Fragile X Syndrome (FXS), which can affect behavior and development. The study is testing a treatment called ZYN002 Transdermal Gel, which contains cannabidiol (CBD). This gel is applied to the skin and is being evaluated for its effectiveness in managing behavioral symptoms associated with FXS in children, adolescents, and young adults aged 3 to under 23 years.

The purpose of the study is to assess how well the ZYN002 gel works and how safe it is for patients with Fragile X Syndrome. Participants in the study will be randomly assigned to receive either the ZYN002 gel or a placebo gel, which looks the same but does not contain the active ingredient. The study will last for a period of 16 weeks, during which participants will apply the gel to their skin as directed. Throughout the study, participants will be monitored to see if there are any changes in their behavior and to ensure their safety.

Researchers will be looking at specific aspects of behavior, such as social interactions and irritability, to determine if there are improvements from the start of the study to the end. The study aims to provide valuable information on whether the ZYN002 gel can be a helpful treatment option for managing symptoms of Fragile X Syndrome.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, the patient will be assessed to ensure they meet the eligibility criteria. This includes being between the ages of 3 and 22, having a diagnosis of Fragile X Syndrome, and being in generally good health.

    The patient must reside with a caregiver who will provide consistent care throughout the study.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted, including a medical history review, physical examination, and laboratory tests. These tests will ensure the patient is suitable for the study.

  3. Step 3

    Treatment phase

    The patient will receive either the ZYN002 Transdermal Gel containing cannabidiol (CBD) or a placebo gel. The gel is applied to the skin.

    The treatment will be administered daily for a period of 18 weeks.

  4. Step 4

    Monitoring and assessments

    Throughout the 18-week treatment period, the patient's behavior and health will be monitored regularly.

    Assessments will include changes in social avoidance and irritability, as well as overall behavior improvements.

  5. Step 5

    Final evaluation

    At the end of the 18-week period, a final evaluation will be conducted to assess the effects of the treatment.

    This will include a review of any changes in behavior and any side effects experienced during the study.

Who can join the trial?

7 criteria

  • Children, adolescents, and young adults who are between 3 and less than 23 years old can participate.
  • The patient must live with a caregiver who will provide consistent care during the study.
  • The patient should be in generally good health, as determined by a doctor, based on medical history, physical check-up, heart test (12-lead ECG), and lab test results. If any lab results are not normal, they must be considered not important for health by both the doctor and the study sponsor.
  • The patient must have a confirmed diagnosis of **Fragile X Syndrome (FXS)**, which is a genetic condition, through genetic testing.
  • If the patient has a history of seizures, they must be on a stable treatment plan with no more than two anti-seizure medications for at least four weeks before the study starts, or they must have been free of seizures for one year if not taking these medications.
  • If the patient is taking medications that affect the mind, such as those for mental health conditions, they should be on a stable plan with no more than three such medications for at least four weeks before the study and must continue this plan during the study. These medications can include antipsychotics, antidepressants, anxiety medications, ADHD medications, and sleep medications.
  • The patient should have a **body mass index (BMI)**, which is a measure of body fat based on height and weight, between 12 and 30. If the BMI is between 30 and 40, the patient must have normal liver function and no family history of fatty liver disease.

Who cannot join the trial?

7 criteria

  • Patients who do not have a diagnosis of Fragile X Syndrome (FXS) cannot participate. FXS is a genetic condition that causes a range of developmental problems.
  • Patients who are younger than 3 years old or older than 22 years old are not eligible.
  • Patients who are not able to use the study medication as a transdermal gel cannot participate. A transdermal gel is a type of medication that is applied to the skin.
  • Patients who have other medical conditions that might interfere with the study results are not eligible.
  • Patients who are currently participating in another clinical trial are not allowed to join this study.
  • Patients who have a history of allergic reactions to similar medications cannot participate.
  • Patients who are unable to follow the study procedures or attend study visits are not eligible.
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

ZYN002 is a transdermal gel being studied for its effectiveness in treating behavioral symptoms in children, adolescents, and young adults with Fragile X Syndrome. This medication is applied to the skin, allowing it to be absorbed into the body. The trial aims to determine how well this gel works in managing symptoms associated with Fragile X Syndrome, which can include anxiety, hyperactivity, and social challenges.

What is already known about the treatment

ZYN002 – ZYN002 is a medication administered as a transdermal gel, meaning it is applied directly to the skin. It is currently being studied in clinical trials for its effectiveness and safety in treating behavioral symptoms associated with Fragile X Syndrome (FXS) in children, adolescents, and young adults. The main therapeutic indication for ZYN002 is to alleviate symptoms related to FXS, a genetic condition that causes a range of developmental problems. At the molecular level, ZYN002 is believed to work by interacting with the endocannabinoid system, which plays a role in regulating mood and behavior. It is classified pharmacologically as a cannabinoid-based therapy.

Investigated diseases

Fragile X Syndrome – Fragile X Syndrome is a genetic disorder caused by a mutation in the FMR1 gene on the X chromosome. It is the most common inherited cause of intellectual disability and autism spectrum disorder. Individuals with Fragile X Syndrome often exhibit developmental delays, learning disabilities, and social and behavioral challenges. Common symptoms include anxiety, hyperactivity, and social avoidance. Physical features may include a long face, large ears, and flexible joints. The severity of symptoms can vary widely among individuals.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-513888-99-00Protocol codeZYN2-CL-033Estimated enrolment204 patientsSponsorHarmony Biosciences Management Inc.

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.