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Study on Long-Term Safety of ZYN002 Gel for Children, Adolescents, and Young Adults with Fragile X Syndrome

InvestigationalNo placebo
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What is this trial about?

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

This clinical trial is focused on studying the long-term effects of a treatment for Fragile X Syndrome, a genetic condition that impacts intellectual and behavioral development. The treatment being tested is called ZYN002 Transdermal Gel, which contains cannabidiol (CBD). This gel is applied to the skin, allowing the medication to be absorbed into the body. The purpose of the study is to assess the safety and tolerability of this treatment over an extended period.

Participants in this study include children, adolescents, and young adults who have previously been involved in a study with the same treatment. They continue to use the gel because their caregivers believe it has been beneficial. The study will last for up to 48 months, during which time the participants will regularly apply the gel and attend follow-up visits to monitor their health and any changes in their symptoms.

Throughout the study, various assessments will be conducted to ensure the safety of the participants. These include physical and neurological examinations, heart tests using a method called 12-lead ECG, and laboratory tests to check blood and urine. Additionally, the study will observe any changes in behavior and symptoms related to Fragile X Syndrome to understand the long-term impact of the treatment. Participants and their caregivers will be asked to provide feedback on any improvements or side effects they notice during the study.

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

    Beginning of the study

    The study involves the use of a medication called ZYN002 Transdermal Gel, which contains cannabidiol (CBD). This gel is applied to the skin.

    The purpose of the study is to assess the long-term safety and tolerability of this gel in individuals with Fragile X Syndrome, a condition that affects intellectual and behavioral development.

  2. Step 2

    Medication administration

    The gel is applied to the skin, a method known as transdermal use. This means the medication is absorbed through the skin.

    The study will last for up to 48 months, during which the gel will be used regularly as directed by the study team.

  3. Step 3

    Safety assessments

    Regular safety assessments will be conducted. These include checking for any side effects, conducting physical and neurological examinations, and performing tests such as ECGs and laboratory assessments.

    The study will also monitor vital signs and conduct skin checks to ensure there is no irritation from the gel.

  4. Step 4

    Progress evaluations

    The study will evaluate changes in behavior and symptoms using specific scales and questionnaires at various intervals, such as months 1, 6, 12, 18, 24, 30, 36, 42, and 48.

    These evaluations will help determine any improvements in social behavior, irritability, and overall condition.

  5. Step 5

    Completion of the study

    The study is expected to conclude by August 31, 2027.

    Participants will continue to be monitored and assessed until the end of the study to ensure their safety and to gather comprehensive data on the long-term effects of the medication.

Who can join the trial?

10 criteria

  • Must have completed the previous study protocol ZYN2-CL-033.
  • Females who can have children must have a negative pregnancy test at all required visits.
  • Children and adolescents, both male and female, aged between 3 and less than 23 years old at the time of joining the previous study.
  • Must be considered in generally good health based on medical history, physical exam, heart test (12-lead ECG), and lab test results. Any lab results that are not normal must be noted as not important for health by both the study doctor and sponsor.
  • If there is a history of seizures, the patient must be on a stable treatment plan with no more than two seizure medications for at least four weeks before joining the study, or must have been free of seizures for one year if not on medication.
  • If taking mental health medications, the patient should be on a stable plan with no more than three such medications for at least four weeks before joining the study. These medications can include those for mental health conditions like anxiety, depression, ADHD, or sleep issues.
  • If receiving non-drug treatments or special diets, these must be stable and ongoing for three months before joining the study.
  • Must have a body mass index (BMI) between 12 and 30, or if BMI is between 30 and 40, must have normal liver function tests and no family history of fatty liver disease. BMI is a measure of body fat based on height and weight.
  • Patients and their parents or caregivers must agree to follow all study rules and procedures, and be considered reliable and willing to follow all study requirements by the study doctor.
  • Patients and their parents or caregivers must be fully informed about the study, understand the risks, and provide written consent before joining the study.

Who cannot join the trial?

8 criteria

  • Patients who have any other serious medical condition that might interfere with the study.
  • Patients who are currently participating in another clinical trial.
  • Patients who have had a significant allergic reaction to any of the ingredients in the study medication.
  • Patients who are unable to follow the study procedures or instructions.
  • Patients who have a history of substance abuse, which means using drugs or alcohol in a way that is harmful.
  • Patients who are pregnant or breastfeeding.
  • Patients who have a condition that affects their skin, as the medication is applied as a gel on the skin.
  • Patients who have a history of seizures, which are sudden, uncontrolled electrical disturbances in the brain.
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Investigated drugs

ZYN002 is a transdermal gel that is applied to the skin. It is being studied for its long-term safety and tolerability in treating symptoms of Fragile X Syndrome in children, adolescents, and young adults. The study aims to see how well patients can tolerate the medication over an extended period, up to 48 months.

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 to assess its long-term safety and tolerability for treating symptoms of Fragile X Syndrome (FXS) in children, adolescents, and young adults. The main therapeutic indication for ZYN002 is Fragile X Syndrome, 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 on the X chromosome, leading to a range of developmental problems. It is the most common inherited cause of intellectual disability and can affect both males and females, though males are typically more severely affected. Individuals with Fragile X Syndrome may exhibit symptoms such as learning disabilities, social and behavioral challenges, and characteristic physical features like an elongated face and large ears. The condition can also be associated with anxiety, hyperactivity, and sensory sensitivities. As individuals with Fragile X Syndrome age, they may experience changes in behavior and cognitive abilities. The severity and specific symptoms can vary widely among those affected.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-508165-33-00Protocol codeZYN2-CL-017Estimated enrolment450 patientsSponsorHarmony Biosciences Management Inc.

sourced from the EU Clinical Trials Register and site verification

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