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Study on Cannabidiol Oral Solution for Infants with Tuberous Sclerosis, Dravet Syndrome, or Lennox-Gastaut Syndrome Experiencing Uncontrolled Seizures

Verified siteRegistered drugNo 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 effects of a treatment for children with certain types of epilepsy, specifically Tuberous Sclerosis Complex, Dravet Syndrome, and Lennox-Gastaut Syndrome. These conditions are known for causing seizures that are difficult to control with standard treatments. The study will use a medication called Cannabidiol, which is provided as an oral solution known by the code name GWP42003-P. Cannabidiol is a chemical compound that is being tested to see if it can help reduce the frequency of seizures in these young patients.

The purpose of the study is to evaluate the safety and effectiveness of this treatment over a period of 52 weeks. Participants will receive the Cannabidiol oral solution in addition to their current seizure medications. The study will monitor how the body processes the medication and its effects on seizure frequency. The trial is open-label, meaning all participants will receive the active treatment, and there is no placebo group. The study will involve regular check-ups to assess the health and development of the participants, as well as to monitor any side effects or changes in seizure patterns.

Throughout the study, caregivers will be asked to keep a diary of the participant's seizures to help researchers understand how well the treatment is working. The study aims to provide valuable information on whether Cannabidiol can be a safe and effective addition to existing treatments for these challenging epilepsy conditions in young children.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    The study begins with an initial assessment to confirm eligibility. This includes reviewing medical history and current medications.

    A video electroencephalogram (VEEG) may be required if not available in the medical record. This test records brain activity to confirm the diagnosis of inadequately controlled seizures.

  2. Step 2

    Baseline period

    During the baseline period, caregivers are required to complete electronic and paper seizure diaries for at least 21 out of 28 days.

    This period helps establish a baseline for seizure frequency and type before starting the treatment.

  3. Step 3

    Treatment initiation

    The treatment involves taking Epidyolex 100 mg/ml oral solution, which contains cannabidiol, by mouth.

    The dosage and frequency are determined by the study team based on individual needs and safety considerations.

  4. Step 4

    Treatment period

    The treatment period lasts for 52 weeks. During this time, the safety and effectiveness of the medication are monitored.

    Regular assessments include checking for any side effects, changes in seizure frequency, and overall health evaluations.

  5. Step 5

    Follow-up assessments

    Throughout the study, caregivers continue to record seizures in diaries every four weeks.

    Blood samples are taken at specific intervals to measure the levels of the medication and its metabolites.

  6. Step 6

    End of treatment

    At the end of the treatment period, a comprehensive assessment is conducted to evaluate the overall impact of the medication.

    This includes a final review of seizure frequency, any new seizure types, and a developmental assessment.

Who can join the trial?

17 criteria

  • Participants must have one of the following conditions: Dravet Syndrome (DS), Tuberous Sclerosis Complex (TSC), or Lennox-Gastaut Syndrome (LGS).
  • Participants with TSC should be between 1 month and less than 2 years old. Participants with DS or LGS should be between 1 year and less than 2 years old.
  • Parents or legal representatives must agree to notify the responsible authorities about the participant's involvement in the study if required by local law.
  • Parents or legal representatives must agree to inform the participant's primary care doctor and consultant about the study participation if they are different from the study investigator.
  • Participants with TSC must have a diagnosis according to the 2012 International Tuberous Sclerosis Complex Consensus Conference. Participants with LGS or DS must have a diagnosis consistent with the International League Against Epilepsy (ILAE) guidelines and confirmed by the Epilepsy Study Consortium (ESCI).
  • Participants must have seizures that are not controlled and are currently taking one or more anti-seizure medications (ASMs).
  • Parents or legal representatives must be willing and able to give informed consent for the participant to join the study.
  • Parents or legal representatives must be willing and able, in the investigator's opinion, to follow all study requirements, including completing an electronic diary about the participant's condition.
  • The caregiver must complete at least 75% of the electronic and paper seizure diary entries during the 28 days before the study starts (at least 21 days of entries).
  • A suitable video electroencephalogram (VEEG) must be available in the medical record within 1 year of the first study visit. If not available, a new VEEG may be done if needed to confirm the diagnosis before the third visit. A suitable VEEG should:
    • Have at least 8 channels for recording brain activity.
    • Record continuously for up to 24 hours.
    • Be completed within 1 year of the first study visit.
    • Match the participant's current seizure pattern, in the investigator's opinion.
    • Be reviewed by both the investigator and an independent reviewer before the third visit.
    • Show that the seizures are not adequately controlled.
    • Participants must be taking at least one ASM at a stable dose for 2 weeks before the third visit and during the treatment period. Changes to ASMs may be allowed for safety reasons after discussing with the medical monitor. Adrenocorticotropic hormone (ACTH) or high-dose corticosteroids for treating infantile spasms or epileptic spasms are considered ASMs.
    • Participants must have seizures that are not adequately controlled with their current ASMs, with at least one seizure reported in the seizure diary during the screening or baseline period.

Who cannot join the trial?

7 criteria

  • Patients with a history of severe allergic reactions to the study medication or its ingredients cannot participate.
  • Individuals who are currently pregnant or breastfeeding are not eligible for the study.
  • Patients with significant liver or kidney disease, which means their liver or kidneys are not working well, cannot join the study.
  • Anyone who has participated in another clinical trial within the last 30 days is excluded.
  • Patients with a history of substance abuse, which means using drugs or alcohol in a harmful way, are not allowed to participate.
  • Individuals with any other medical condition that the study doctors believe would make it unsafe for them to participate are excluded.
  • Patients who are unable to comply with the study procedures, meaning they cannot follow the study rules or attend appointments, cannot join the study.
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Investigated drugs

Cannabidiol Oral Solution (GWP42003-P) is being studied as an additional treatment for young children with certain types of epilepsy, including Tuberous Sclerosis Complex, Dravet Syndrome, and Lennox-Gastaut Syndrome. This medication is used to help reduce the number of seizures in children whose seizures are not well controlled with their current treatments. The study aims to understand how safe and tolerable this medication is over a year-long period and how it is processed in the body.

What is already known about the treatment

Cannabidiol Oral Solution (GWP42003-P) – This medication is administered orally in the form of a solution. It is currently being studied in clinical trials for its safety, pharmacokinetics, and efficacy in treating young children with Dravet Syndrome, Tuberous Sclerosis Complex, and Lennox-Gastaut Syndrome who experience seizures that are not well-controlled by other treatments. Cannabidiol works by interacting with the endocannabinoid system in the brain, which may help reduce seizure frequency. It is classified as a cannabinoid, a type of compound found in cannabis plants.

Investigated diseases

  • Dravet Syndrome

    Dravet Syndrome is a rare, severe form of epilepsy that begins in infancy. It is characterized by prolonged seizures that are often triggered by fever or hot temperatures. As the child grows, other types of seizures may develop, including myoclonic and absence seizures. The condition can also lead to developmental delays and behavioral challenges. Children with Dravet Syndrome may experience difficulties with balance and coordination. The frequency and severity of seizures can vary widely among individuals.

  • Tuberous Sclerosis Complex

    Tuberous Sclerosis Complex is a genetic disorder that causes non-cancerous tumors to form in many different organs, primarily the brain, eyes, heart, kidneys, skin, and lungs. The condition can lead to a variety of symptoms, including seizures, developmental delays, and skin abnormalities. The severity of symptoms can vary greatly, even among members of the same family. Tumors in the brain can cause neurological problems, while those in other organs may lead to additional health issues. The condition is caused by mutations in either the TSC1 or TSC2 genes. It is often diagnosed in childhood, but symptoms can appear at any age.

  • Lennox-Gastaut Syndrome

    Lennox-Gastaut Syndrome is a complex, rare form of epilepsy that typically begins in early childhood. It is characterized by multiple types of seizures, including tonic and atonic seizures, and often results in cognitive impairment. The condition is associated with a slow spike-and-wave pattern on an electroencephalogram (EEG). Children with Lennox-Gastaut Syndrome may experience developmental delays and behavioral problems. The frequency and type of seizures can change over time, making management challenging. The cause of Lennox-Gastaut Syndrome can vary, with some cases linked to brain injuries or infections.

Trial detailsLast updated 7 Oct 2026
Age0-17PhasePhase IIITrial ID2023-505851-33-00Protocol codeGWEP17005Estimated enrolment27 patientsSponsorJazz Pharmaceuticals Research UK Limited

sourced from the EU Clinical Trials Register and site verification

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