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Long-Term Safety Study of Fenfluramine Hydrochloride for Seizures in Patients with Dravet or Lennox-Gastaut Syndrome

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 long-term safety of a medication called fenfluramine hydrochloride, also known by its code name ZX008. The study is designed for individuals with rare seizure disorders, specifically Dravet syndrome and Lennox-Gastaut syndrome. These are types of epileptic encephalopathies, which are severe forms of epilepsy that begin in childhood and are characterized by frequent seizures and developmental delays.

The purpose of the study is to assess how safe and tolerable fenfluramine hydrochloride is when used over a long period as an additional treatment for seizures. Participants in the study will take the medication in the form of an oral solution. The study will monitor the participants' health and any side effects they may experience while taking the medication. This includes regular check-ups and various health assessments to ensure the safety of the participants.

Throughout the study, participants will continue to receive the medication and will be observed for any changes in their condition. The study aims to provide valuable information on the long-term use of fenfluramine hydrochloride in managing seizures associated with these rare disorders. This research is important for understanding how the medication can help improve the quality of life for those affected by these challenging conditions.

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

    Joining the study

    Participation begins after satisfactory completion of a core study related to rare seizure disorders such as Dravet syndrome or Lennox-Gastaut syndrome.

    Eligibility requires being male or a nonpregnant, nonlactating female, and having successfully completed another clinical trial with the study medication.

  2. Step 2

    Medication administration

    The study involves taking fenfluramine hydrochloride as an oral solution.

    The medication is used as an additional therapy for managing seizures.

  3. Step 3

    Monitoring and assessments

    Regular monitoring includes checking for any adverse effects, conducting laboratory tests, and measuring vital signs such as blood pressure, heart rate, temperature, and respiratory rate.

    Physical and neurological examinations are performed periodically.

  4. Step 4

    Specialized tests

    Tests such as electrocardiograms (ECGs) and Doppler echocardiograms (ECHOs) are conducted to assess heart function.

    In specific countries, additional tests like chest x-rays and electroencephalograms (EEGs) are performed.

  5. Step 5

    Evaluation of effectiveness

    The effectiveness of the treatment is evaluated through assessments by both the caregiver and the investigator.

    The evaluation includes measuring the improvement in seizure frequency and overall condition.

  6. Step 6

    Study duration

    The study is designed to assess the long-term safety and tolerability of the medication, with an estimated end date of June 30, 2025.

Who can join the trial?

5 criteria

  • The patient must be a male or a nonpregnant, nonlactating female. This means women who are not pregnant and not breastfeeding.
  • The patient must have satisfactorily completed a core study. This means they have finished a previous part of the research successfully.
  • The patient must have a rare seizure disorder, such as epileptic encephalopathy. This is a condition where seizures are frequent and can affect brain function.
  • The patient must have successfully completed another clinical trial with the study medication, ZX008, sponsored by Zogenix.
  • The patient's caregiver must be willing and able to follow the study procedures, attend scheduled visits, and manage the study medication properly. A caregiver is someone who helps take care of the patient.

Who cannot join the trial?

5 criteria

  • Patients who do not have **Dravet syndrome** or **Lennox-Gastaut syndrome** cannot participate. These are specific types of epilepsy that cause severe seizures.
  • Patients who are not within the specified age range cannot participate. The study is for certain age groups, which are not detailed here.
  • Patients who are not part of the specified clinical trial groups cannot participate. This means the study is looking for people with specific characteristics or conditions.
  • Patients who are not male or female cannot participate. The study includes both genders.
  • Patients who are not considered part of a vulnerable population cannot participate. Vulnerable populations may include groups like children or those with certain health conditions.
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Investigated drugs

ZX008 (Fenfluramine Hydrochloride) is an oral solution used as an additional treatment for seizures. It is specifically aimed at helping patients with rare seizure disorders, including conditions like Dravet Syndrome and Lennox-Gastaut Syndrome. The purpose of using this medication in the trial is to evaluate its long-term safety and how well patients can tolerate it when used alongside their existing seizure treatments.

What is already known about the treatment

Fenfluramine Hydrochloride – This medication is administered orally in the form of a solution. It is currently being studied in clinical trials to evaluate its long-term safety and tolerability as an adjunctive therapy for seizures in patients with rare seizure disorders, specifically Dravet syndrome and Lennox-Gastaut syndrome. Fenfluramine works by influencing serotonin levels in the brain, which helps to reduce the frequency and severity of seizures. It is classified as a serotonin-releasing agent and is being explored for its potential benefits in managing these challenging conditions.

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, speech impairment, and motor difficulties. Children with Dravet syndrome may experience behavioral challenges and have an increased risk of sudden unexplained death in epilepsy (SUDEP). The syndrome is often associated with a genetic mutation in the SCN1A gene.

  • 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, atonic, and atypical absence seizures. The condition often leads to developmental delays and cognitive impairment. Children with Lennox-Gastaut syndrome may also experience behavioral problems and difficulties with coordination. The seizures are usually resistant to standard epilepsy treatments, making management challenging. The cause of Lennox-Gastaut syndrome can vary, including brain malformations, genetic disorders, or unknown factors.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-515680-61-00Protocol codeZX008-1900(EP0215)Estimated enrolment325 patientsSponsorZogenix International Limited

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