MedPath

An Open-label Study of XEN1101 in Epilepsy

Phase 3
Conditions
Focal Epilepsy
Tonic-Clonic Seizures
Interventions
Registration Number
NCT05718817
Lead Sponsor
Xenon Pharmaceuticals Inc.
Brief Summary

This study will evaluate the long term safety, tolerability, pharmacokinetics (PK), and efficacy of XEN1101 in subjects with Focal Onset Seizures (FOS) or Primary Generalized Tonic-Clonic Seizures (PGTCS) for the treatment of seizures for up to 3 years.

Detailed Description

This is an Open Label Extension study of the following Phase 3 clinical studies: XPF-010-301 (X-TOLE2), XPF-010-302 (X-TOLE3), and XPF-010-303 (X-ACKT). This study will evaluate the long-term safety, tolerability, PK, and efficacy of XEN1101 in subjects with FOS or PGTCS for the treatment of seizures for up to 3 years. Subjects who successfully completed and did not terminate early from one of the antecedent studies (X-TOLE2, X-TOLE3, or X-ACKT) are eligible to participate in X-TOLE4.

Following enrollment into X-TOLE4, subjects will undergo a treatment period of up to 3 years, during which there will be a visit at 2-, 4-, and 13-weeks post-entry, with subsequent visits occurring at 13-week intervals during the first year, and then at 26-week intervals (with a telephone call in between) until dosing is completed.

Subjects will be initially assigned to XEN1101 as follows:

* 25 mg QD for subjects aged ≥18 years

* For subjects aged ≥12 and \<18 years

* 15 mg QD for those

* who weigh \<45 kg at the start of the X-TOLE4 study

* who weighed \<45 kg during the X-ACKT study

* who weighed ≥45 kg at randomization in the X-ACKT study and had dose reduction(s) for intolerability

* 25 mg QD for all others

Subjects will be instructed to orally take XEN1101 once daily (QD) with an evening meal. Subjects will be expected to keep a daily seizure eDiary with a minimum of 80% compliance for the duration of the extension study (reporting on ≥80% of days between visits).

Upon completion of dosing at the end of the treatment period, there will be an 8-week follow up period.

Recruitment & Eligibility

Status
ENROLLING_BY_INVITATION
Sex
All
Target Recruitment
880
Inclusion Criteria
  1. Subject must be properly informed of the nature and risks of the study and give informed consent in writing prior to entering the study (for adult subjects) and for adolescent subject's parent/legal guardian and subject gives informed consent or assent in writing prior to entering the study.
  2. Subject must have successfully completed the double-blind treatment period (DBP) and have not terminated early from Study X-TOLE2, X-TOLE3, or X-ACKT, met all eligibility requirements, and had no important protocol deviations (in the opinion of the sponsor) or adverse events (AEs) (in the opinion of the investigator) that would preclude the subject's entry into the long-term extension study.
  3. In the opinion of the investigator, the subject is able to understand verbal and written instructions and will adhere to all study schedules and requirements.
  4. Subject is able to keep accurate seizure diaries.
Exclusion Criteria
  1. Subject met any of the withdrawal criteria while in Study X-TOLE2, X-TOLE3, or X-ACKT.
  2. Subject has any medical condition, personal circumstance, or ongoing AE (from Study X-TOLE2, X-TOLE3, or X-ACKT) that, in the opinion of the investigator, exposes the subject to unacceptable risk by participating in the study, or prevents adherence to the protocol.
  3. Subject is planning to enter a clinical study with a different investigational drug or planning to use any experimental device for treatment of epilepsy or any other medical condition during the study and until 28 days after completion of this study.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
XEN1101 15 or 25 mg/dayXEN1101XEN1101 15 or 25 mg/day
Primary Outcome Measures
NameTimeMethod
The adverse eventsFrom the start of treatment in the open-label extension (OLE) study through 8 weeks after the last dose.

To assess the safety and tolerability of XEN1101

Secondary Outcome Measures
NameTimeMethod
Change in Clinical Global Impression of Severity (CGI-S)From baseline through the active extension treatment (Week 156).

Improvement in Clinical Global Impression of Severity (CGI-S) scores over time.

Change in monthly seizure rateFrom baseline through the active extension treatment (Week 156).

Percent change in monthly seizure rate recorded at baseline (in the antecedent studies) compared to each 4-week assessment period in the treatment period in X-TOLE4.

Proportion of respondersFrom baseline through the active extension treatment (Week 156).

Proportion of responders (subjects experiencing ≥50% reduction in seizure frequency from baseline) in each consecutive 4-week assessment period of the treatment period of the OLE study.

Change in Quality of Life in Epilepsy Inventory (QOLIE-31)From baseline through the active extension treatment (Week 156).

Change in the 31-Item Quality of Life in Epilepsy Inventory (QOLIE-31) over time.

Change in Patient Global Impression of Severity (PGI-S)From baseline through the active extension treatment (Week 156).

Improvement in Patient Global Impression of Severity (PGI-S) scores over time.

Trial Locations

Locations (97)

Hospital Clinico San Carlos

🇪🇸

Madrid, Spain

Hospital Universitario Fundación Jiménez Díaz

🇪🇸

Madrid, Spain

Hospital Regional De Malaga

🇪🇸

Málaga, Spain

Hospital La Fe

🇪🇸

Valencia, Spain

St George's Hospital NHS Foundation Trust

🇬🇧

London, United Kingdom

University College London

🇬🇧

London, United Kingdom

STAT Research S.A.

🇦🇷

Buenos Aires, Argentina

FLENI (Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia)

🇦🇷

Buenos Aires, Argentina

MHATNP St. Naum

🇧🇬

Sofia, Bulgaria

Motol University Hospital

🇨🇿

Prague, Czechia

Forbeli s.r.o.

🇨🇿

Prague, Czechia

Hopital Neurologique Pierre Wertheimer, Hospices Civils de Lyon

🇫🇷

Lyon, France

Hôpital Fondation Adolphe de Rothschild

🇫🇷

Paris, France

Krankenhaus Mara gGmbH

🇩🇪

Bielefeld, Germany

Vall d'Hebron Hospital

🇪🇸

Barcelona, Spain

Hospital Vithas La Milagrosa

🇪🇸

Madrid, Spain

Cardiff and Vale UHB

🇬🇧

Cardiff, Wales, United Kingdom

Hospital Ramón Y Cajal

🇪🇸

Madrid, Spain

Hospital Ruber Internacional

🇪🇸

Madrid, Spain

Mater Misericordiae Ltd South Brisbane

🇦🇺

South Brisbane, Australia

Providence Neurological Specialities

🇺🇸

Portland, Oregon, United States

Clinical Trials, Inc

🇺🇸

Little Rock, Arkansas, United States

Brain Science Research Institute

🇺🇸

Los Angeles, California, United States

UC Irvine Health

🇺🇸

Orange, California, United States

University of Colorado Hospital Anschutz Outpatient Pavilion

🇺🇸

Aurora, Colorado, United States

Research Institute of Orlando, LLC

🇺🇸

Orlando, Florida, United States

Panhandle Research & Medical Clinic

🇺🇸

Pensacola, Florida, United States

Hawaii Pacific Neuroscience

🇺🇸

Honolulu, Hawaii, United States

Consultants in Epilepsy and Neurology

🇺🇸

Boise, Idaho, United States

Indiana University School of Medicine

🇺🇸

Indianapolis, Indiana, United States

The University of Kansas Medical Center

🇺🇸

Kansas City, Kansas, United States

Bluegrass Epilepsy Research, LLC

🇺🇸

Lexington, Kentucky, United States

Kentucky Clinic

🇺🇸

Lexington, Kentucky, United States

MMP Neurology

🇺🇸

Scarborough, Maine, United States

Mid-Atlantic Epilepsy and Sleep Center

🇺🇸

Bethesda, Maryland, United States

University of Michigan Hospitals

🇺🇸

Ann Arbor, Michigan, United States

Michigan State University

🇺🇸

East Lansing, Michigan, United States

Cornwell Health (Spectrum Health Hospitals)

🇺🇸

Grand Rapids, Michigan, United States

Northeast Epilepsy Group

🇺🇸

Hackensack, New Jersey, United States

Montefiiore Medical Center

🇺🇸

Bronx, New York, United States

Dent Neurosciences Research Center

🇺🇸

Buffalo, New York, United States

New York University Comprehensive Epilepsy Center

🇺🇸

New York, New York, United States

Mount Sinai Health

🇺🇸

New York, New York, United States

SUNY Upstate Medical University

🇺🇸

Syracuse, New York, United States

Duke University

🇺🇸

Durham, North Carolina, United States

Meridian Clinical Research, LLC

🇺🇸

Raleigh, North Carolina, United States

Summa Health

🇺🇸

Akron, Ohio, United States

Queen Elizabeth Hospital Birmingham

🇬🇧

Birmingham, United Kingdom

Thomas Jefferson University

🇺🇸

Philadelphia, Pennsylvania, United States

Hospital Clinico Universitario de Valladolid

🇪🇸

Valladolid, Spain

Vanderbilt University Medical Center

🇺🇸

Nashville, Tennessee, United States

Austin Epilepsy Care Center

🇺🇸

Austin, Texas, United States

ANESC Research

🇺🇸

El Paso, Texas, United States

University of Utah Clinical Neurosciences Center

🇺🇸

Salt Lake City, Utah, United States

Carilion Clinic

🇺🇸

Roanoke, Virginia, United States

Sentara Neurology Specialists

🇺🇸

Virginia Beach, Virginia, United States

University of Washington Main Hospital

🇺🇸

Seattle, Washington, United States

Aurora St. Luke's Medical Center

🇺🇸

Milwaukee, Wisconsin, United States

Hospital General de Agudos "José M. Ramos Mejía"

🇦🇷

Buenos Aires, Argentina

Hospital De Alta Complejidad en Red El Cruce - Dr Nester Carlos Kirchner Servicio de Atencion Medica Integral Para la Communidad

🇦🇷

Florencio Varela, Argentina

Sanatorio del SUR S.A.

🇦🇷

Tucumán, Argentina

Royal Prince Alfred Hospital

🇦🇺

Camperdown, Australia

Austin Health Pharmacy Clinical Trials

🇦🇺

Heidelberg, Australia

Southern Neurology

🇦🇺

Kogarah, Australia

Alfred Hospital Neurology CT Dept of Neuroscience

🇦🇺

Melbourne, Australia

The Royal Melbourne Hospital

🇦🇺

Parkville, Australia

Westmead Hospital Dept. of Neurology Epilepsy Unit

🇦🇺

Westmead, Australia

University Hospital Innsbruck

🇦🇹

Innsbruck, Austria

Hospital for active treatmnt Puls AD Neurology Dpt

🇧🇬

Blagoevgrad, Bulgaria

Center for Neurologic Research

🇨🇦

Lethbridge, Alberta, Canada

Centro de investigación Clinica UC

🇨🇱

Santiago, Chile

Altavita Centar j.d.o.o.

🇭🇷

Zagreb, Croatia

University Hospital Centre Zagreb

🇭🇷

Zagreb, Croatia

Universitätsklinikum, ZNN - Epilepsiezentrum Frankfurt Rhein-Main

🇩🇪

Frankfurt, Germany

Klinikum der Universität München

🇩🇪

München, Germany

Universitaets-Und Rehabilitations Ulm (RKU)

🇩🇪

Ulm, Germany

Semmelweis Egyetem, Idegsebeszeti es Neurointervencios Klinika

🇭🇺

Budapest, Hungary

Hadassah Medical Center (HMC)

🇮🇱

Jerusalem, Israel

Kaplan Medical Center (KMC)

🇮🇱

Reẖovot, Israel

The Tel Aviv Sourasky Medical Center

🇮🇱

Tel Aviv, Israel

IRCCS Istituto delle Scienze Neurologiche Bologna

🇮🇹

Bologna, Italy

Universita' Degli Studi Gabriele d'Annunzio Di Chieti

🇮🇹

Chieti, Italy

Azienda Ospedaliero Universitaria Pisana

🇮🇹

Pisa, Italy

Grupo Medico Camino SC

🇲🇽

Ciudad de México, Mexico

Human Science Research Trials

🇲🇽

Mexico City, Mexico

Centrum Medyczne Neuromed

🇵🇱

Bydgoszcz, Poland

COPERNICUS Podmiot Leczniczy Sp. z o.o.

🇵🇱

Gdańsk, Poland

NZOZ Neuromed M. i M.

🇵🇱

Lublin, Poland

Twoja Przychodnia Nowosolskie Centrum Medyczne

🇵🇱

Nowa Sól, Poland

MTZ Clinical Research Powered by Pratia

🇵🇱

Warsaw, Poland

Centro Hospitalar Universitário de Coimbra (CHUC)

🇵🇹

Coimbra, Portugal

Hospital Senhora da Oliviera de Guimaraes

🇵🇹

Guimarães, Portugal

Centro Hospitalar Lisboa Ocidental, EPE - Hospital Egas Moniz

🇵🇹

Lisboa, Portugal

Centro Hospitalar Universitario de Santo António, E.P.E

🇵🇹

Porto, Portugal

Unidade Local Saúde Matosinhos

🇵🇹

Porto, Portugal

Centro Hospitalar de Entre o Douro e Vouga

🇵🇹

Santa Maria Da Feira, Portugal

Hospital Universitario Cruces

🇪🇸

Baracaldo, Spain

© Copyright 2025. All Rights Reserved by MedPath