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Study on the Effects of Azetukalner in Reducing Focal-Onset Seizures for Patients with Epilepsy

Fast replyInvestigationalNo 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 on individuals with focal onset seizures. Focal onset seizures are a type of epilepsy where seizures start in one area of the brain. The medication being tested, XEN1101, is taken in the form of a capsule and is being evaluated for its ability to reduce the frequency of these seizures. The study will compare the effects of XEN1101 to a placebo, which is a capsule that looks like the medication but does not contain the active substance.

The purpose of this study is to assess how well XEN1101 works in reducing the number of seizures experienced by participants. Participants will be randomly assigned to receive either XEN1101 or a placebo. The study will last for a period of 12 weeks, during which participants will take the capsules daily. Throughout the study, participants will be monitored to see if there is a reduction in the frequency of their seizures and to evaluate the safety and tolerability of the medication.

This trial is designed to provide valuable information on the potential benefits of XEN1101 as an additional treatment for people with focal onset seizures. The results will help determine if XEN1101 can be an effective option for managing this type of epilepsy. Participants will be required to keep a diary of their seizures to help researchers understand the impact of the treatment. The study aims to contribute to the development of new therapies for individuals living with epilepsy.

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, you will be asked to provide written consent, confirming that you understand the nature and risks of the study.

    You must have a diagnosis of focal epilepsy for at least two years and have tried at least two anti-seizure medications without achieving sustained seizure freedom.

  2. Step 2

    Baseline period

    During this period, you will continue taking your current anti-seizure medications at a stable dose. This will last for at least one month before the study begins.

    You will be required to keep an accurate diary of your seizures.

  3. Step 3

    Double-blind period

    In this phase, you will receive either the study medication, XEN1101, or a placebo. The medication is in the form of a capsule taken orally.

    The dosage and frequency of the medication will be determined by the study team, and you will continue this treatment throughout the double-blind period.

  4. Step 4

    Monitoring and assessment

    Your seizure frequency will be monitored throughout the study. The primary goal is to assess whether there is a reduction in your seizure frequency.

    You will be asked to report any changes in your condition and any side effects you experience.

  5. Step 5

    End of study

    At the end of the study, your overall response to the treatment will be evaluated.

    You will be informed about the results and any next steps regarding your treatment.

Who can join the trial?

7 criteria

  • The person must be properly informed about the nature and risks of the study and must give written consent to participate.
  • The person must have been diagnosed with focal epilepsy for at least 2 years. This means they have a type of epilepsy where seizures start in one area of the brain.
  • The person must have tried at least 2 different anti-seizure medications (ASMs) at the right doses, but these did not stop the seizures completely.
  • The person must be taking a stable dose of 1 to 3 allowed anti-seizure medications (ASMs) for at least 1 month before the study starts and continue this during the study.
  • The person must be able to keep accurate records of their seizures in a diary.
  • The study is open to both males and females.
  • The study includes people who might be considered vulnerable, meaning they might need extra protection or care.

Who cannot join the trial?

5 criteria

  • Patients who do not have Focal Onset Seizures cannot participate.
  • Patients who are not within the specified age range cannot participate.
  • Patients who are not part of the specified clinical trial groups cannot participate.
  • Patients who are not male or female cannot participate.
  • Patients who are considered part of a vulnerable population cannot participate.
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Investigated drugs

XEN1101 is a medication being studied to see if it can help reduce the number of seizures in people who have focal-onset seizures. Focal-onset seizures start in one specific area of the brain and can affect a person's awareness or cause movements in parts of the body. This medication is being tested as an additional treatment, which means it is used along with other seizure medications that a person might already be taking. The goal of the study is to find out if XEN1101 is safe to use and if it can effectively lower the frequency of these seizures.

What is already known about the treatment

XEN1101 – XEN1101 is administered orally and is currently being studied in a Phase 3 clinical trial to evaluate its safety, tolerability, and effectiveness as an additional treatment for focal onset seizures. This medication is not yet widely used in medicine, as it is still under investigation, but it shows promise in reducing the frequency of these seizures. XEN1101 works by targeting specific channels in the brain that help control electrical activity, which can help prevent seizures. It is classified as an anticonvulsant, a type of drug used to prevent or reduce the severity of epileptic seizures.

Investigated diseases

Focal Onset Seizures – Focal onset seizures, also known as partial seizures, begin in one specific area of the brain. They can cause a variety of symptoms depending on the brain region affected, such as unusual sensations, movements, or changes in behavior. These seizures may be classified as either aware or impaired awareness, depending on whether consciousness is maintained. As the seizure progresses, it can spread to other parts of the brain, potentially leading to a generalized seizure. The duration of focal onset seizures can vary, typically lasting from a few seconds to a couple of minutes. They may occur sporadically or in clusters, with frequency varying among individuals.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-502000-73-00Protocol codeXPF-010-301Estimated enrolment360 patientsSponsorXenon Pharmaceuticals Inc.

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).