RecruitingPHASE3INTERVENTIONAL

A Randomized Study of XEN1101 Versus Placebo in Focal-Onset Seizures (X-TOLE3)

This research study, called X-TOLE3, is looking at a new medicine called XEN1101 for adults who have focal-onset seizures. These are seizures that start in one part of the brain. The study wants to find out if XEN1101 can help reduce the number of seizures and if it's safe to use. Participants will be randomly given either XEN1101 or a dummy pill (placebo) alongside their usual seizure medications. This helps researchers compare the new medicine fairly. The study lasts about 12 weeks, with a chance to continue taking XEN1101 if the study goes well. It's for people aged 18 and over who have been diagnosed with focal epilepsy for at least two years.

At a glance

Status

Recruiting

Phase

PHASE3

Sponsor

Xenon Pharmaceuticals Inc.

Enrolment target

360

Start

09 May 2023

Estimated completion

01 Dec 2026

Focal Onset Seizures

What is this study about?

This study, called X-TOLE3, is exploring a new medicine named XEN1101. It's designed for people who experience focal-onset seizures, which means their seizures begin in a specific area of the brain. The main goal of this research is to see if XEN1101 can effectively reduce the number of seizures people have and if it's a safe medicine to use. The study is particularly interested in whether XEN1101 can be a helpful addition to the seizure medications people are already taking.

To ensure fair testing, this study uses a method called 'randomised and double-blind'. This means that participants are randomly assigned to one of three groups: one group will receive a 25mg dose of XEN1101, another group a 15mg dose, and the third group will receive a placebo (a dummy pill with no active medicine). Neither the participants nor their doctors will know which treatment they are receiving, which helps prevent any bias. This allows the researchers to accurately compare how well XEN1101 works against not taking the active drug.

Finding new and effective treatments for focal-onset seizures is important because over time, some people find that their current medications don't fully control their seizures. If XEN1101 proves to be safe and effective, it could offer a new option for people living with this condition, potentially improving their quality of life by reducing seizure frequency.

Key takeaways

This study is testing a new medicine (XEN1101) for focal-onset seizures.
It aims to see if XEN1101 can reduce seizures and is safe to use.
Participants will be randomly assigned XEN1101 or a dummy pill (placebo).
You must continue taking your existing seizure medications.
The main treatment period lasts 12 weeks, with options for longer-term access to the medicine.

Who may be eligible?

To join this study, you must be at least 18 years old and have been diagnosed with focal epilepsy for at least two years. You should have tried at least two other seizure medicines at a good dose, but these haven't fully stopped your seizures. You also need to be taking 1 to 3 stable seizure medicines right now and be able to keep a clear record of your seizures.

There are also some reasons why you might not be able to join. For example, if your brain scans show a different type of seizure, or if you only have very mild seizures that don't affect your ability to move or speak. You also can't join if your seizures are caused by things like drug or alcohol use, an ongoing infection, certain serious brain conditions, or if you've had certain brain surgeries or severe, continuous seizures recently. The study also cannot include you if your doctor believes it wouldn't be safe for you to take part.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Have you been diagnosed with focal epilepsy for at least 2 years?
Do you currently take 1 to 3 stable seizure medications?
Have other seizure medicines not fully controlled your seizures?
Are you able to accurately record your seizures in a diary?

Answer every question to see your result.

What does participation involve?

If you decide to join this study, it will involve several steps. First, you'll have a period of up to 9.5 weeks where doctors will simply observe your usual seizures to get a good idea of how often they happen. During this time, you'll need to accurately record your seizures in a diary.

After this observation period, you'll then take either the study medicine (XEN1101) or a dummy pill once a day with your evening meal for 12 weeks. Neither you nor your doctor will know which one you're taking. Throughout this 12-week period, you'll continue to take your regular seizure medicines at a stable dose. You'll also need to keep a detailed seizure diary during this time.

Once the 12-week active treatment period is over, you might have the option to join another part of the study where everyone receives XEN1101 openly. If you don't join this next phase, you'll have an 8-week follow-up period after you stop the study medicine. The total duration of your involvement could be several months, depending on whether you join the follow-on study.

Potential risks and benefits

Participating in research always has potential benefits and risks. A potential benefit of joining this study is that you might receive a new medicine (XEN1101) that could help reduce your seizures, possibly more effectively than your current treatment. However, there's also a chance you'll receive the placebo (dummy pill) and not get the active treatment, meaning your seizures might not improve. As with any new medicine, XEN1101 could have side effects, which the study will carefully monitor. You will be closely monitored by medical professionals throughout the study. Remember, joining is completely voluntary, and you have the right to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (95)

Clinical Trials, Inc.
Verified postcode
Little Rock, United States· Recruiting
Rancho Research Institute
Verified postcode
Downey, United States· Recruiting
University of California Los Angeles (UCLA)
Verified postcode
Los Angeles, United States· Recruiting
University of California Irvine Health
Verified postcode
Orange, United States· Recruiting
Panhandle Research and Medical Clinic
Verified postcode
Gulf Breeze, United States· Recruiting
Mayo Clinic Florida
Verified postcode
Jacksonville, United States· Recruiting
Consultants in Epilepsy and Neurology, PLLC
Verified postcode
Boise, United States· Recruiting
Southern Illinois University School of Medicine
Verified postcode
Springfield, United States· Recruiting
Mid-Atlantic Epilepsy and Sleep Center
Verified postcode
Bethesda, United States· Recruiting
9D University Health Center
Verified postcode
Detroit, United States· Recruiting
Northeast Regional Epilepsy Group
Verified postcode
Hackensack, United States· Recruiting
Five Towns Neuroscience Research
Verified postcode
Woodmere, United States· Withdrawn

Common questions

What are focal-onset seizures?

Focal-onset seizures are a type of seizure that starts in just one specific area of your brain, common in focal epilepsy.

What is a 'placebo'?

A placebo is a 'dummy pill' that looks exactly like the study medicine but doesn't contain any active drug. It helps researchers compare how well the real medicine works.

Will I know if I'm getting the real medicine or the placebo?

No, neither you nor your doctor will know if you're taking XEN1101 or the placebo during the main part of the study. This is called 'double-blind' and ensures fair results.

Can I continue taking my own seizure medicines?

Yes, you must continue taking your usual seizure medicines at a stable dose throughout the study. XEN1101 is tested as an 'add-on' treatment.

What happens after the 12 weeks of treatment?

You might be able to continue taking XEN1101 in another part of the study, or you'll have an 8-week follow-up period to check on your health.

How to find out more

Xenon Medical Affairs

xenoncares@xenon-pharma.com 1-604-484-3300 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.