MedPath

A Study to Evaluate XEN1101 as Adjunctive Therapy in Primary Generalized Tonic-Clonic Seizures

Phase 3
Recruiting
Conditions
Primary Generalized Tonic-Clonic Seizures
Interventions
Drug: Placebo
Registration Number
NCT05667142
Lead Sponsor
Xenon Pharmaceuticals Inc.
Brief Summary

This is a Phase 3, multicenter, randomized, double-blind, placebo-controlled study to evaluate the clinical efficacy, safety, and tolerability of XEN1101 administered as adjunctive treatment in primary generalized tonic-clonic seizures (PGTCS).

Detailed Description

This is a Phase 3, multicenter, randomized, double-blind, placebo-controlled study to evaluate the clinical efficacy, safety, and tolerability of XEN1101 administered as adjunctive treatment in subjects diagnosed with generalized epilepsy and experiencing probable or possible PGTCS (with or without other subtypes of generalized seizures), and taking 1 to 3 anti-seizure medications (ASMs). Eligible subjects will be randomly assigned 1:1 to XEN1101 or placebo: subjects aged ≥ 18 years will receive XEN1101 25 mg or placebo, and subjects aged ≥12 years and \<18 years will receive either XEN1101 15 mg, 25 mg, or placebo. Randomization will be stratified based on region, age group, and background use of CYP3A4-inducer ASMs. Eligible subjects will have up to 9.5 weeks durations to assess the baseline frequency of seizures, followed by a double-blind treatment period (DBP) where subjects will receive 12 weeks of blinded treatment. During the DBP, subjects will be instructed to orally take XEN1101 or placebo once daily with an evening meal.

Subjects who complete the 12-week DBP will have the opportunity to enroll in a separate open-label-extension (OLE) study for continued treatment with XEN1101. Subjects who do not enroll in the OLE will enter an 8 week post-treatment follow-up period.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
160
Inclusion Criteria
  1. Subject is properly informed of the nature and risks of the study and gives informed consent in writing prior to entering the study (for adult subjects) and for adolescent subjects parent/legal guardian and subject gives informed consent or assent in writing prior to entering the study.
  2. Subject is ≥12 years of age with a BMI ≤40 kg/m2 at Visit 1.
  3. Subject must have had adequate trials of at least 2 ASMs, which were given (and tolerated) at adequate therapeutic doses, without achieving sustained seizure freedom.
  4. Subject has probable or possible PGTCS (with or without other subtypes of generalized seizures) for ≥1 year, in the setting of generalized epilepsy according to the International League Against Epilepsy 2017 classification criteria, and subject is approved by The Epilepsy Study Consortium (TESC).
  5. Subject is on a stable dose of 1 to 3 allowable current ASMs for at least 1 month prior to screening (Visit 1), during screening/baseline, and throughout the DBP.
  6. Subject is able to keep accurate seizure diaries.
Exclusion Criteria
  1. Subject has had status epilepticus within the 12 months prior to Visit 1.

  2. Subject has history of repetitive seizures within the 12-month period preceding Visit 1 where the individual seizures cannot be counted.

  3. Subject has a history of non-epileptic psychogenic seizures.

  4. Subject has a concomitant diagnosis of focal-onset seizures (FOS).

  5. Subject has presence or history of a developmental and epileptic encephalopathy, including Lennox-Gastaut syndrome.

  6. Subject has seizures secondary to drug or alcohol use, ongoing infection, neoplasia, demyelinating disease, degenerative neurological disease, metabolic illness, progressive structural lesion, encephalopathy, or progressive central nervous system (CNS) disease.

  7. Subject has history of neurosurgery for seizures <1 year prior to Visit 1, or radiosurgery <2 years prior to Visit 1.

  8. Subject has schizophrenia and other psychotic disorders (eg, schizophreniform disorder, schizoaffective disorder, psychosis not otherwise specified), bipolar disorder, obsessive-compulsive disorder, or another serious mental health disorder. Subject has uncontrolled unipolar major depression where changes in pharmacotherapy are needed or anticipated during the study.

  9. Subject has any clinically significant laboratory abnormalities or clinically significant abnormalities on prestudy physical examination, vital signs, or ECG that, in the judgment of the investigator, indicate a medical problem that would preclude study participation, including but not limited to:

    a. History or presence of long QT syndrome; QTcF >450 msec at baseline; family history of sudden death of unknown cause.

  10. Any personal circumstance that, in the opinion of the investigator, prevents adherence to the protocol.

The criteria to be eligible for randomization are:

  1. During the last 56 days of the baseline period that preceded the randomization visit (Visit 2), subject must have had a sufficient documented seizure frequency of PGTCS, including ≥1 PGTCS during each of the first and second 4-week periods preceding randomization.
  2. Seizure diary was completed a minimum of 80% of all days (ie, ≥45 days) during the last 56 days of the baseline period that preceded randomization as evidence of adequate compliance.
  3. Subject did not change dose of, stop, or initiate any new ASM(s) during the baseline period and plans on maintaining a stable dose of ASM(s) during the DBP.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
XEN1101 25 mg/dayXEN1101XEN1101 25 mg/day
XEN1101 15 mg/dayXEN1101XEN1101 15 mg/day
PlaceboPlaceboPlacebo
Primary Outcome Measures
NameTimeMethod
Median percent change (MPC) in monthly (28 days) PGTCS frequencyBaseline through DBP (Week 12)

Median percent change (MPC) in monthly (28 days) PGTCS frequency from baseline through the DBP for XEN1101 versus placebo.

Secondary Outcome Measures
NameTimeMethod
Proportion of subjectsBaseline through Week 12

Proportion of subjects experiencing PGTCS freedom from baseline through the DBP for XEN1101 versus placebo.

Trial Locations

Locations (129)

MHATNP 'Sveti Naum' EAD

🇧🇬

Sofia, Bulgaria

University Hospital Center Zagreb

🇭🇷

Zagreb, Croatia

Neurociencias Estudios Clínicos S.C

🇲🇽

Sinaloa, Mexico

Kempenhaeghe

🇳🇱

Heeze, Netherlands

Centrum Medyczne Neuromed

🇵🇱

Bydgoszcz, Poland

COPERNICUS Podmiot Leczniczy Sp. z o.o.

🇵🇱

Gdańsk, Poland

Novo-Med Zielinski I Wspolnicy Sp. J.

🇵🇱

Katowice, Poland

NZOZ Neuromed M. i M.

🇵🇱

Lublin, Poland

Twoja Przychodnia Nowosolskie Centrum Medyczne

🇵🇱

Nowa Sól, Poland

Centro Hospitalar Universitário de Coimbra (CHUC)

🇵🇹

Coimbra, Portugal

Hospital da Senhora da Oliveira

🇵🇹

Guimarães, Portugal

Centro Hospitalar Lisboa Ocidental, Hospital Egas Moniz

🇵🇹

Lisboa, Portugal

Centre Hospitalar Universitario de Lisboa Norte (CHULN)

🇵🇹

Lisboa, Portugal

Hospital Clinico Viña del Mar

🇪🇸

Valparaiso, Spain

Azienda Ospedaliero Universitaria Pisana

🇮🇹

Pisa, Italy

Ospedalo Pediatrico Bambino Gesu

🇮🇹

Roma, Italy

University of Alabama - Strada Patient Care Center, Neurology

🇺🇸

Mobile, Alabama, United States

Xenoscience

🇺🇸

Phoenix, Arizona, United States

University of Arizona - Health Science Center

🇺🇸

Tucson, Arizona, United States

University of Arkansas for Medical Sciences

🇺🇸

Little Rock, Arkansas, United States

Brain Science Research Institute

🇺🇸

Los Angeles, California, United States

University of California, Irvine - Health Neurology Services

🇺🇸

Orange, California, United States

University California, Davis Clinical & Translation Science Center Clinical Research (CCRC)

🇺🇸

Sacramento, California, United States

University of Colorado Anschutz Medical Campus

🇺🇸

Aurora, Colorado, United States

Serenity Research Center, LLC

🇺🇸

Miami, Florida, United States

Research Institute of Orlando, LLC

🇺🇸

Orlando, Florida, United States

Panhandle Research and Medical Clinic

🇺🇸

Pensacola, Florida, United States

Medsol Clinical Research Center Harbor Professional Centre

🇺🇸

Port Charlotte, Florida, United States

University of South Florida

🇺🇸

Tampa, Florida, United States

Encore Medical Research of Weston, LLC

🇺🇸

Weston, Florida, United States

Emory Brain Health Center

🇺🇸

Atlanta, Georgia, United States

Children's Healthcare of Atlanta

🇺🇸

Atlanta, Georgia, United States

Georgia Neurology & Sleep Medicine Associates

🇺🇸

Suwanee, Georgia, United States

Hawaii Pacific Neuroscience, Comprehensive Epilepsy Center

🇺🇸

Honolulu, Hawaii, United States

Consultants in Epilepsy and Neurology, PLLC

🇺🇸

Boise, Idaho, United States

Universitätsklinik für Neurologie, Medizinische Universität Wien

🇦🇹

Vienna, Austria

Southern Illinois University School of Medicine

🇺🇸

Springfield, Illinois, United States

Indiana University School of Medicine

🇺🇸

Indianapolis, Indiana, United States

University of Kansas Medical Center

🇺🇸

Kansas City, Kansas, United States

Bluegrass Epilepsy Research, LLC

🇺🇸

Lexington, Kentucky, United States

University of Kentucky Albert B. Chandler Hospital (UK Healthcare)

🇺🇸

Lexington, Kentucky, United States

University of Maryland Medical Center

🇺🇸

Baltimore, Maryland, United States

MedStar Franklin Square Medical Center

🇺🇸

Baltimore, Maryland, United States

Mid-Atlantic Epilepsy and Sleep Center

🇺🇸

Bethesda, Maryland, United States

Medstar Georgetown University Hospital

🇺🇸

Clinton, Maryland, United States

Brigham and Women's Hospital

🇺🇸

Chestnut Hill, Massachusetts, United States

UMass Memorial Medical Center

🇺🇸

Worcester, Massachusetts, United States

University of Michigan Hospitals

🇺🇸

Ann Arbor, Michigan, United States

Wayne State University

🇺🇸

Detroit, Michigan, United States

Michigan State University Department of Neurology

🇺🇸

East Lansing, Michigan, United States

Spectrum Health

🇺🇸

Grand Rapids, Michigan, United States

Northeast Regional Epilepsy Group

🇺🇸

Hackensack, New Jersey, United States

Dent Neurosciences Research Facility

🇺🇸

Amherst, New York, United States

SUNY Upstate Medical University

🇺🇸

Syracuse, New York, United States

Five Towns Neurology

🇺🇸

Woodmere, New York, United States

Onsite Clinical Solutions, LLC

🇺🇸

Charlotte, North Carolina, United States

Wake Forest Baptist Health

🇺🇸

Winston-Salem, North Carolina, United States

Summa Health Clinical Research Center

🇺🇸

Akron, Ohio, United States

Cleveland Clinic Foundation

🇺🇸

Cleveland, Ohio, United States

The Ohio State University

🇺🇸

Columbus, Ohio, United States

OhioHealth Riverside Methodist Hospital

🇺🇸

Columbus, Ohio, United States

University of Pennsylvania

🇺🇸

Philadelphia, Pennsylvania, United States

Temple University Hospital

🇺🇸

Philadelphia, Pennsylvania, United States

Medical University of South Carolina (MUSC)

🇺🇸

Charleston, South Carolina, United States

ANESC Research

🇺🇸

El Paso, Texas, United States

UTHealth Science Center at Houston

🇺🇸

Houston, Texas, United States

University of Texas Health Science Center at San Antonio

🇺🇸

San Antonio, Texas, United States

University of Utah Clinical Neurosciences Center

🇺🇸

Salt Lake City, Utah, United States

Sentara Neurology Specialists

🇺🇸

Virginia Beach, Virginia, United States

University of Washington, Regional Epilepsy Center at Harborview Medical Center

🇺🇸

Seattle, Washington, United States

Advocate Aurora Research institute, St. Luke's Medical Center

🇺🇸

Milwaukee, Wisconsin, United States

Hospital General de Agudos J.M. Ramos Mejia

🇦🇷

Buenos Aires, Argentina

STAT Research S.A.

🇦🇷

Buenos Aires, Argentina

Hospital Italiano

🇦🇷

Buenos Aires, Argentina

Sanatorio del Sur S.A

🇦🇷

San Miguel De Tucumán, Argentina

Southern Neurology

🇦🇺

Kogarah, New South Wales, Australia

Mater Misericordiae Ltd

🇦🇺

South Brisbane, Queensland, Australia

Austin Health Pharmacy Clinical Trials

🇦🇺

Heidelberg, Victoria, Australia

The Alfred Hospital

🇦🇺

Melbourne, Victoria, Australia

St Vincent's Hospital Melbourne, Clinical Neurosciences

🇦🇺

Melbourne, Victoria, Australia

The Royal Melbourne Hospital

🇦🇺

Parkville, Australia

University Hospital Innsbruck

🇦🇹

Innsbruck, Austria

Universitaetsklinik fuer Kinder

🇦🇹

Linz, Austria

Universitätsklinik für Neurologie

🇦🇹

Salzburg, Austria

Multiprofile hospital for active treatment Puls AD

🇧🇬

Blagoevgrad, Bulgaria

First University Multiprofile Hospital for Active Treatment Sofia Sv. Joan Krastitel

🇧🇬

Sofia, Bulgaria

Center for Neurologic Research

🇨🇦

Lethbridge, Alberta, Canada

Children and Women's Health Centre of BC (BC Children's Hospital)

🇨🇦

Vancouver, British Columbia, Canada

London Health Sciences Center

🇨🇦

London, Ontario, Canada

Le Centre Hospitalier de l'Universite' de Montreal (CHUM)

🇨🇦

Montréal, Quebec, Canada

Clinical Hospital Center Osijek

🇭🇷

Osijek, Croatia

Clinical Hospital Center Rijeka

🇭🇷

Rijeka, Croatia

Fakultni nemocnice v Motole Neurologicka klinika 2. LF UK a FN Motol

🇨🇿

Prague, Czechia

CHU de Lille, Hôpital Roger Salengro - Neurophysiologie clinique

🇫🇷

Lille, France

Hopital Neurologique Pierre Wertheimer, Hospices Civils de Lyon

🇫🇷

Lyon, France

Hôpital Fondation A. de Rothschild

🇫🇷

Paris, France

CHU de Rennes - Hôpital Pontchaillou

🇫🇷

Rennes, France

CHU de Strasbourg - Hôpital de Hautepierre

🇫🇷

Strasbourg, France

Universitätsklinikum Aachen

🇩🇪

Aachen, Germany

Vivantes Humboldt Klinikum

🇩🇪

Berlin, Germany

Bethel Epilepsy Centre

🇩🇪

Bielefeld, Germany

Universitätsklinikum Frankfurt

🇩🇪

Frankfurt, Germany

Philipps-Universität Marburg

🇩🇪

Marburg, Germany

Klinikum der Universität München

🇩🇪

München, Germany

Epilepsiezentrum Kleinwachau gemeinnützige GmbH

🇩🇪

Radeberg, Germany

Universitätsklinikum Tübingen

🇩🇪

Tuebingen, Germany

Universitätsklinikum Ulm

🇩🇪

Ulm, Germany

Hadassah University Medical Center

🇮🇱

Jerusalem, Israel

The Chaim Sheba Medical Center

🇮🇱

Ramat Gan, Israel

Kaplan Medical Center

🇮🇱

Reẖovot, Israel

The Tel Aviv Sourasky Medical Center

🇮🇱

Tel Aviv, Israel

Azienda Ospedaliero Universitaria Ospedali Riuniti Ancona

🇮🇹

Ancona, Italy

Università Degli Studi Gabriele d'Annunzio Di Chieti

🇮🇹

Chieti, Italy

Policlinico Umberto I

🇮🇹

Roma, Italy

Grupo Medico Camino SC

🇲🇽

Ciudad de México, Mexico

Human Science Research Trials S. de R.L. de C.V.

🇲🇽

Mexico City, Mexico

Unidade Local de Saúde de Matosinhos

🇵🇹

Matosinhos, Portugal

Centro Hospitalar Universitário de Santo António

🇵🇹

Porto, Portugal

Centro Hospitalar de Entre o Douro e Vouga

🇵🇹

Santa Maria Da Feira, Portugal

Hospital Universitario 12 de Octubre

🇪🇸

Madrid, Spain

Hospital Universitario Vithas Madrid La Milagrosa

🇪🇸

Madrid, Spain

Hospital Regional Universitario de Málaga

🇪🇸

Málaga, Spain

Hospital Clinico Universitario de Valladolid

🇪🇸

Valladolid, Spain

University Hospital of Wales

🇬🇧

Cardiff, Wales, United Kingdom

Mid Yorkshire Hospitals NHS Trust

🇬🇧

Wakefield, West Yorkshire, United Kingdom

St George's University Hospitals NHS Foundation Trust

🇬🇧

London, United Kingdom

University College London Hospitals NHS Foundation Trust

🇬🇧

London, United Kingdom

John Radcliffe Hospital

🇬🇧

Oxford, United Kingdom

Salford Royal NHS Foundation Trust - Greater Manchester Neuroscience Centre (GMNC)

🇬🇧

Salford, United Kingdom

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