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Study on the Long-term Safety and Tolerability of Azetukalner for Patients with Epilepsy, Including Focal-onset and Primary Generalized Tonic-Clonic Seizures

Verified siteInvestigationalNo 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 medication called XEN1101 in people diagnosed with epilepsy. Specifically, it looks at two types of seizures: focal-onset seizures, which start in one area of the brain, and primary generalized tonic-clonic seizures, which affect the whole brain. The medication being tested, XEN1101, is taken in the form of a capsule and is designed to help manage these types of seizures.

The purpose of this study is to understand how safe and tolerable long-term use of XEN1101 is for people with epilepsy. Participants in the study will take the medication over a period of time, and researchers will monitor them to see how they respond to the treatment. This includes looking at any side effects they might experience and how their seizure frequency changes. The study will also assess the overall impact on participants' quality of life and any changes in their health over time.

Throughout the study, participants will be asked to take the medication regularly and attend scheduled check-ups. These check-ups will help researchers gather important information about the medication's effects. The study aims to provide valuable insights into the long-term use of XEN1101 for managing epilepsy, which could help improve treatment options for people living with this condition.

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 participant will begin a long-term evaluation of the medication XEN1101, which is designed to assess its safety and effectiveness for individuals diagnosed with epilepsy.

    The study is open-label, meaning that both the participant and the researchers will know which treatment is being administered.

  2. Step 2

    Medication administration

    The participant will take the medication XEN1101 in the form of a capsule. The route of administration is oral.

    The specific dosage and frequency of the medication will be determined by the study protocol and communicated to the participant by the study team.

  3. Step 3

    Monitoring and assessments

    Throughout the study, the participant will undergo regular assessments to monitor the safety and tolerability of the medication. This includes tracking any side effects and changes in health status.

    The participant will also be required to maintain accurate seizure diaries to record the frequency and severity of seizures.

  4. Step 4

    Evaluation of treatment effects

    The study will evaluate the change in seizure frequency over time, comparing the baseline rate to each 4-week assessment period.

    Additional assessments will include changes in quality of life and other health-related scores.

  5. Step 5

    Completion of the study

    The study is expected to continue until September 2028, with the participant's involvement lasting as long as they meet the study requirements and choose to remain in the study.

    Upon completion, the participant will undergo final assessments to evaluate the long-term effects of the medication.

Who can join the trial?

6 criteria

  • The patient must have completed the previous study periods without leaving early and met all the necessary requirements. They should not have had any major issues or side effects that would prevent them from joining this long-term study.
  • The patient should be able to keep accurate records of their seizures.
  • The patient must be fully informed about the study, including its nature and risks, and must agree to participate by signing a written consent form before joining the study.
  • The patient must agree to follow the study's rules about birth control as described in the study's guidelines.
  • Male patients must agree not to donate sperm until 3 months after their last dose of the study medication. Female patients must agree not to donate eggs until 6 months after their last dose of the study medication.
  • The patient should be able to understand both spoken and written instructions and be willing to follow all the study schedules and requirements, according to the study doctor's opinion.

Who cannot join the trial?

4 criteria

  • Patients who have not completed Study XPF-010-301, XPF-010-302, or XPF-010-303 cannot participate.
  • Patients who are not within the specified age range for the study cannot participate.
  • Patients who do not have the specific types of seizures being studied, such as Focal-onset Seizures or Primary generalized tonic-clonic seizures, cannot participate.
  • Patients who are part of a vulnerable population, which means they might need special protection or care, cannot participate.
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Investigated drugs

XEN1101 is a medication being studied for its safety and tolerability in people with epilepsy. It is designed to help manage seizures in patients who have already participated in previous studies. The trial aims to understand how well patients can tolerate this medication over a long period and to observe any potential side effects.

What is already known about the treatment

XEN1101 – XEN1101 is an investigational medication administered orally, currently being studied in clinical trials for its safety and effectiveness in treating epilepsy, specifically focal-onset seizures and primary generalized tonic-clonic seizures. It is not yet approved for general medical use, but ongoing research aims to establish its long-term safety and tolerability. The medication works by modulating potassium channels in the brain, which helps stabilize neuronal activity and reduce seizure frequency. XEN1101 is classified as an anticonvulsant, a type of drug used to prevent or reduce the severity of epileptic seizures.

Investigated diseases

  • Focal-onset Seizures

    These seizures begin in one specific area of the brain and can affect consciousness or awareness. They may cause unusual sensations, emotions, or movements, depending on the part of the brain involved. As the seizure progresses, it can spread to other areas of the brain, potentially leading to a generalized seizure. Symptoms can vary widely, including muscle twitching, changes in vision, or a sense of déjà vu. The duration of these seizures can range from a few seconds to a couple of minutes. They are often followed by a period of confusion or fatigue.

  • Primary Generalized Tonic-Clonic Seizures

    These seizures involve the entire brain from the onset and are characterized by a combination of muscle stiffness (tonic phase) and rhythmic muscle contractions (clonic phase). They typically begin with a sudden loss of consciousness, followed by a period of muscle rigidity and then convulsions. The person may cry out, fall, and experience muscle jerks, often leading to a brief period of confusion or deep sleep afterward. These seizures usually last a few minutes and can be accompanied by a loss of bladder control or biting of the tongue. They are often followed by a period of drowsiness or confusion known as the postictal state.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-502282-24-00Protocol codeXPF-010-304Estimated enrolment880 patientsSponsorXenon Pharmaceuticals Inc.

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