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

Phase 3
Recruiting
Conditions
Focal Onset Seizures
Interventions
Drug: Placebo
Registration Number
NCT05716100
Lead Sponsor
Xenon Pharmaceuticals Inc.
Brief Summary

The X-TOLE3 Phase 3 clinical trial is a randomized, double-blind, placebo-controlled study that will evaluate the clinical efficacy, safety and tolerability of XEN1101 administered as adjunctive therapy in focal-onset seizures.

Detailed Description

Approximately 360 subjects will be randomized in a blinded manner to one of two active treatment groups or placebo in a 1:1:1 fashion (XEN1101 25 mg : 15 mg : Placebo). Eligible subjects will have up to 9.5 weeks of baseline to assess frequency of seizures, followed by 12 weeks of blinded treatment. In order to be included in the study, subjects must be treated with a stable dose of 1 to 3 allowable antiseizure medications (ASMs) for at least one month prior to screening, during baseline, and throughout the double-blind treatment period (DBP) of the study. 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 qualify and enroll in a separate open-label extension (OLE) study for continued treatment with XEN1101. Subjects who do not enroll in the OLE will enter a 8-week post treatment follow-up period.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
360
Inclusion Criteria
  • Be properly informed of the nature and risks of the study and give informed consent in writing, prior to entering the study
  • Diagnosis (≥2 years) of focal epilepsy according to the International League Against Epilepsy (ILAE) Classification of Epilepsy (2017). 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.
  • Treatment with a stable dose of 1 to 3 allowable current ASMs for at least one month prior to screening, during baseline, and throughout the duration of the DBP
  • Able to keep accurate seizure diaries
Exclusion Criteria
  • Previously documented electroencephalogram which shows any pattern not consistent with focal etiology of seizures.
  • History of focal aware non-motor seizures only, non-epileptic psychogenic seizure, primary generalized seizure, developmental and epileptic encephalopathy, including Lennox-Gastaut syndrome.
  • 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.
  • History of status epilepticus or repetitive seizures within the 12-month period preceding Visit 1 where the individual seizures cannot be counted.
  • History of neurosurgery for seizures <1 year prior to Visit 1, or radiosurgery <2 years prior to enrollment.
  • Any medical condition or personal circumstance that, in the opinion of the investigator, exposes the subject to unacceptable risk by participating in the study or prevents adherence to the protocol.

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 focal seizure frequency from baseline to DBP for XEN1101 versus placebo.From baseline through to the double blind period (week 12).
Secondary Outcome Measures
NameTimeMethod
Proportion of subjects experiencing ≥50% reduction in focal seizure frequency from baseline through the DBP for XEN1101 versus placebo.From baseline through to the double blind period (week 12).
MPC in weekly (7 days) focal seizure frequency from baseline to Week 1 for XEN1101 versus placebo.From baseline through to the week 1.
Proportion of subjects experiencing "at least much improved" (including "much" and "very much improved") in Patient Global Impression of Change (PGI-C).From baseline through to the double blind period (week 12).
To assess adverse events as criteria for safety and tolerability of XEN1101.From screening through to 56 days post-final dose

Trial Locations

Locations (66)

Centro de Investigacion Clinica UC

🇨🇱

Santiago, Chile

CINSAN

🇨🇱

Santiago, Chile

Hospital Clínico Viña del Mar

🇨🇱

Viña Del Mar, Chile

University Hospital Center Osijek

🇭🇷

Osijek, Croatia

Cliniques Universitaires Saint-Luc (UCL)

🇧🇪

Brussels, Belgium

Rancho Research Institute

🇺🇸

Downey, California, United States

University of California Irvine Health

🇺🇸

Orange, California, United States

Southern Illinois University School of Medicine

🇺🇸

Springfield, Illinois, United States

9D University Health Center

🇺🇸

Detroit, Michigan, United States

Five Towns Neuroscience Research

🇺🇸

Woodmere, New York, United States

University of Utah Clinical Neurosciences Center

🇺🇸

Salt Lake City, Utah, United States

CENyR Centro de Especialidades Neurologicas y Rehabilitacion

🇦🇷

C.a.b.a., Argentina

FLENI

🇦🇷

C.a.b.a., Argentina

Universitätsklinik für Neurologie

🇦🇹

Salzburg, Austria

Medical center OPHTHA-NEURO

🇧🇬

Sofia, Bulgaria

Vanderbilt University Medical Center

🇺🇸

Nashville, Tennessee, United States

Cleveland Clinic

🇺🇸

Cleveland, Ohio, United States

OhioHealth

🇺🇸

Columbus, Ohio, United States

Policlinico Lomas

🇦🇷

Buenos Aires, Argentina

Hospital Ramos Mejia

🇦🇷

Buenos Aires, Argentina

Hospital De Alta Complejidad en Red el Cruce

🇦🇷

Buenos Aires, Argentina

Sanatori del Sur S.A.

🇦🇷

San Miguel De Tucumán, Argentina

Medical University of Vienna

🇦🇹

Vienna, Austria

Hospital Italiano

🇦🇷

Buenos Aires, Argentina

STAT Resarch S.A.

🇦🇷

Buenos Aires, Argentina

University Hospital Innsbruck

🇦🇹

Innsbruck, Austria

Clinica Universidad de Los Andes

🇨🇱

Santiago, Chile

Universitair Ziekenhuis Gent

🇧🇪

Ghent, Belgium

MHATNPsy Sveti Naum EAD

🇧🇬

Sofia, Bulgaria

Clinical Hospital Center Rijeka, Klinika za Neurologiju

🇭🇷

Rijeka, Croatia

Poliklinika Bonifarm

🇭🇷

Zagreb, Croatia

University Hospital Center Zagreb

🇭🇷

Zagreb, Croatia

Poliklinika LF MEDICAL

🇭🇷

Zagreb, Croatia

EUC Hradec Kralove Clinic

🇨🇿

Hradec Králové, Czechia

Nemocnicni lekarna FN Motol / Motol University Hospital

🇨🇿

Prague, Czechia

Forbeli s.r.o.

🇨🇿

Prague, Czechia

Hopital Neurologique Pierre Wertheimer

🇫🇷

Bron, France

Centre Hospitalier Universitaire de Lille (CHU de Lille)

🇫🇷

Lille, France

Hôpital de la Pitié Salpêtrière

🇫🇷

Paris, France

Hôpital de Hautepierre

🇫🇷

Strasbourg, France

Universitätsklinikum Aachen

🇩🇪

Aachen, Germany

Semmelweis Egyetem, Idegsebészeti és Neurointervenciós Klinika

🇭🇺

Budapest, Hungary

Hôpital Fondation A. de Rothschild

🇫🇷

Paris, France

Chu de Rennes Hôpital Pontchaillou

🇫🇷

Rennes, France

Hadassah 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

Ospedali Riuniti di Ancona

🇮🇹

Ancona, Italy

Università degli studi di Bari Aldo Moro

🇮🇹

Bari, Italy

Grupo Medico Camino

🇲🇽

Benito Juárez, Mexico

Human Science Research Trials

🇲🇽

Mexico City, Mexico

Neurocencias Esudios Clinicos S.C.

🇲🇽

Sinaloa, Mexico

Kempenhaeghe

🇳🇱

Heeze, Netherlands

COPERNICUS Podmiot Leczniczy

🇵🇱

Gdańsk, Poland

NZOZ Neuromed M. i M. Nastaj Sp. P.

🇵🇱

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 da Senhora da Oliveira

🇵🇹

Guimarães, Portugal

Centro Hospitalar de Lisboa Norte

🇵🇹

Lisbon, Portugal

Centro Hospitalar Lisboa Ocidental

🇵🇹

Lisbon, Portugal

Centro Hospitalar Universitário de Santo António

🇵🇹

Porto, Portugal

Hospital Pedro Hispano

🇵🇹

Porto, Portugal

Centro Hospitalar de Entre o Douro e Vouga

🇵🇹

Santa Maria Da Feira, Portugal

Hospital Universitario Cruces

🇪🇸

Barakaldo, Spain

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