MedPath

A Study of Soticlestat as an Add-on Therapy in Children, Teenagers, and Adults With Lennox-Gastaut Syndrome

Phase 3
Completed
Conditions
Lennox Gastaut Syndrome (LGS)
Interventions
Drug: Placebo
Registration Number
NCT04938427
Lead Sponsor
Takeda
Brief Summary

The aims of the study are:

* to learn if soticlestat, when given as add-on therapy, reduces the number of major motor drop seizures in children, teenagers, and adults with Lennox-Gastaut Syndrome.

* to assess the safety profile of soticlestat when given in combination with other therapies.

Participants will receive their standard antiseizure therapy, plus either tablets of soticlestat or placebo. A placebo looks just like soticlestat but will not have any medicine in it. Participants will take soticlestat or placebo for 16 weeks, followed by a gradual dose reduction for 1 week. Then, participants will be followed up for 2 weeks.

Detailed Description

The drug being tested in this study is called soticlestat (TAK-935). Soticlestat will be assessed for efficacy, safety, and tolerability in pediatric and adult participants with LGS.

The study will enroll approximately 234 patients. Participants will be randomly assigned (by chance, like flipping a coin) in a 1:1 ratio to receive standard of care (SOC) plus one of the following adjunctive therapies which will remain undisclosed to the participant and study doctor during the study (unless there is an urgent medical need):

1. Soticlestat

2. Placebo (dummy inactive pill - this is a tablet/mini-tablet that looks like the study drug but has no active ingredient)

Participants will receive soticlestat or matching placebo based on their weight in the 4-week Titration Period. Following the Titration Period, participants will continue to receive the same dose in the 12-week Maintenance Period. The dose will then be down-tapered if participants decide to discontinue the treatment and/or are not deemed eligible to continue in Open-label extension (OLE).

This multi-center trial will be conducted worldwide. The overall time to participate in the study will be from 22-25 weeks. At the end of the treatment period, participants have the option to either complete the study and taper off the investigational product or to enter the OLE if they meet eligibility requirements. If participants discontinue, they will be followed-up on phone call approximately 14 days after the last dose of study drug for safety.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
270
Inclusion Criteria
  1. Has documented clinical diagnosis of LGS.
  2. Has had ≥8 MMD seizures each month in the 3 months prior to Screening based on the historical information and has had ≥8 MMD seizures per 28 days during the 4 to 6 week prospective Baseline Period.
  3. Weighs ≥10 kg at the Screening Visit (Visit 1).
  4. Failure to control seizures despite appropriate trials of at least 1 ASM based on historical information, and is currently on an antiseizure therapy or other treatment options considered as standard of care (SOC).
  5. Artisanal cannabidiols are allowed at a stable dose for at least 4 weeks before the screening visit (Visit 1); the dosing regimen and manufacturer should remain constant throughout the study. (Artisanal cannabidiols will not be counted as ASMs.)
  6. Currently taking 0 to 3 ASMs at stable doses for at least 4 weeks before the Screening Visit (Visit 1); Fenfluramine and cannabidiol (Epidiolex) are allowed where available and counted as an ASM. ASM dosing regimen must remain constant throughout the study.
Exclusion Criteria
  1. Admitted to a medical facility and intubated for treatment of status epilepticus 2 or more times in the 3 months immediately before Screening (Visit 1). For the purpose of this exclusion criterion, status is defined as continuous seizure activity lasting longer than 5 minutes or repeated seizures without return to Baseline in between seizures.
  2. Unstable, clinically significant neurologic (other than the disease being studied), psychiatric, cardiovascular, ophthalmologic, pulmonary, hepatic, renal, metabolic, gastrointestinal, urologic, immunologic, hematopoietic, endocrine disease, malignancy including progressive tumors, or other abnormality that may impact the ability to participate in the study or that may potentially confound the study results. It is the responsibility of the investigator to assess the clinical significance; however, consultation with the medical monitor may be warranted.
  3. Considered by the investigator to be at imminent risk of suicide or injury to self, others, or property, or the participant has attempted suicide within 12 months before the Screening Visit (Visit 1). Participants who have positive answers on item numbers 4 or 5 on the Columbia suicide severity rating scale (C-SSRS) before dosing (Visit 2) are excluded. This scale will only be administered to participants aged ≥6 years.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
SoticlestatSoticlestatParticipants weighing \<45 kg: Soticlestat, mini-tablets, at the dose of 40 mg to 200 mg, orally or via G-tube or MIC-KEY button or J-tube, BID based on body weight up to 4 weeks during titration. Participants continued to receive the dose that they were on at the end of the titration, for 12 weeks during maintenance. The total duration of the treatment was up to 16 weeks (Full Treatment Period) with the dose tapered down if participants decided to discontinue the treatment. Participants weighing ≥45 kg: Soticlestat mini-tablets or tablets with a starting dose of 100 mg BID followed by 200 mg BID and, then 300 mg BID, up to 4 weeks during titration. Participants continued to receive 300 mg BID for 12 weeks during maintenance. The total duration of the treatment was up to 16 weeks (Full Treatment Period) with the dose tapered down if participants decided to discontinue the treatment.
PlaceboPlaceboSoticlestat placebo-matching mini-tablets or tablets, orally or via G-tube or MIC-KEY button or J-tube, BID, up to 4 weeks during titration. Participants continued to receive soticlestat placebo-matching mini-tablets or tablets for 12 weeks during maintenance. The total duration of the treatment was up to 16 weeks (Full Treatment Period). Soticlestat matching tapering was done to maintain the blind if participants decided to discontinue the treatment.
Primary Outcome Measures
NameTimeMethod
Percent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Full Treatment PeriodBaseline; Full Treatment Period: Weeks 1 to 16

MMD seizure frequency per 28 days was defined as the total number of MMD seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the full Treatment Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Percent Change From Baseline in Major Motor Drop (MMD) Seizure Frequency Per 28 Days During the Maintenance PeriodBaseline; Maintenance Period: Weeks 5 to 16

MMD seizure frequency per 28 days was defined as the total number of MMD seizures reported during the period divided by number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the Maintenance Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Secondary Outcome Measures
NameTimeMethod
Longest MMD Seizure-free Interval During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16

Longest MMD Seizure-free Interval was defined as the longest time period that the participant remained MMD seizure-free after initiation of the treatment. A linear model with treatment group and age stratum as factors was used for analysis.

Number of Days When Rescue Antiseizure Medication (ASM) is Used During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16

Use of rescue ASM was recorded in the case report form (CRF) along with start and end date of medication. Based on

the start and end dates for all rescue ASMs taken by a participant, the number of days during the Full Treatment Period when rescue ASM was used was derived.

Percentage of Responders During the Maintenance PeriodMaintenance Period: Weeks 5 to 16

Responders are defined as those with ≥50% reduction from Baseline in MMD seizures during the Maintenance Period. Percentages are rounded off to the nearest single decimal place.

Percentage of Responders During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16

Responders are defined as those with ≥50% reduction from Baseline in MMD seizures during the Full Treatment Period. Percentages are rounded off to the nearest single decimal place.

Percentage of Participants With ≤0%, >0% to ≤25%, >25% to ≤50%, >50% to ≤75%, >75% to ≤100% Reduction in MMD Seizure During the Full Treatment PeriodFull Treatment Period: Weeks 1 to 16

Percent reduction from Baseline (%) is defined as \[(Full Treatment Period MMD Seizure Frequency - Baseline MMD Seizure Frequency) divided by Baseline MMD Seizure Frequency\] multiplied by 100. Data is reported as reduction of ≤0%, \>0% to ≤25%, \>25% to ≤50%, \>50% to ≤75%, \>75% to ≤100% or more in seizures from Baseline. Percentages are rounded off to the nearest single decimal place.

Percentage of Participants With Caregiver Global Impression of Improvement (Care GI-I) Scale Responses as Per the Parent/Caregiver Reported Impression at Week 16Week 16

The Care GI-I is a 7-point Likert scale that the caregiver used to rate improvement in overall seizure control, behavior, safety and tolerability after the initiation of study drug relative to Baseline (before treatment with the study drug). The participant was rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). The parent/caregiver completed the Care GI-I via interview. Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.

Percentage of Participants With Clinical Global Impression of Improvement (CGI-I) Scale Responses as Per the Investigator Reported Impression at Week 16Week 16

The CGI-I (Clinician) is a 7-point Likert scale that the investigator to rate a participant's change (improvement) in overall seizure control, behavior, safety and tolerability after the initiation of study drug relative to Baseline (before treatment with the study drug). The participant was rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). The investigator or designee will complete the CGI-I. Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.

Percentage of Participants With CGI-I Nonseizure Symptoms Instrument Responses for Each Domain as Per the Investigator Reported Impression at Week 16Week 16

The CGI-I nonseizure symptoms instrument is a series of single-item assessments that the investigator used to rate improvement in the symptoms and impacts in select nonseizure domains (alertness, communication, and disruptive behaviors) since initiating the study drug. The participant was rated by the investigator for each domain as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). Lower scores indicated improvement. Data for percentage of participants categorized based on the responses for each domain are presented. Percentages are rounded off to the nearest single decimal place.

Change From Baseline in Quality of Life Inventory-Disability (QI-Disability) Total Score at Week 16Baseline, Week 16

The QI-Disability tool is a parent/caregiver-reported questionnaire evaluated the quality of life in children with intellectual disabilities. It contains 32 items covering 6 domains of quality of life: physical health, positive emotions, negative emotions, social interaction, leisure and the outdoors, and independence. Each QI-Disability item is rated on a Likert scale of: Never, Rarely, Sometimes, Often, and Very Often. Items were linearly transformed to a scale of 0 to 100, with higher scores representing better quality of life. Domain scores are calculated by averaging item scores. The domain scores are summed and divided by 6 to yield a total score. The total score ranges from 0 to 100, with higher scores indicating a better quality of life. A negative change from Baseline implies deteriorating quality of life. Mixed-effects model for repeated measures (MMRM) was used for analysis.

Percentage of Participants With CGI-I Seizure Intensity and Duration Instrument Responses as Per the Parent/Caregiver Reported Impression at Week 16Week 16

The CGI-I seizure intensity and duration instrument was used by the parent/caregiver to rate changes in intensity and/or duration of the most impactful seizures from the first assessment. The participant's symptoms were rated as follows: 1 (very much improved), 2 (much improved), 3 (minimally improved), 4 (no change), 5 (minimally worse), 6 (much worse), and 7 (very much worse). Lower scores indicate improvement. Percentages are rounded off to the nearest single decimal place.

Percent Change From Baseline in Frequency of All Seizures Per 28 Days During the Maintenance PeriodBaseline; Maintenance Period: Weeks 5 to 16

Seizure frequency per 28 days was defined as the total number of seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the Maintenance Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Percent Change From Baseline in Frequency of All Seizures Per 28 Days During the Full Treatment PeriodBaseline; Full Treatment Period: Weeks 1 to 16

Seizure frequency per 28 days was defined as the total number of seizures reported during the period divided by the number of days during the period seizures were assessed multiplied by 28. Percent change from Baseline was defined as (frequency of seizures per 28 days during the full Treatment Period - frequency of seizures per 28 days at Baseline) divided by the frequency of seizures per 28 days at Baseline multiplied by 100.

Change From Baseline in Percentage of MMD Seizure-free Days During the Full Treatment PeriodBaseline up to Week 16

MMD Seizure-free days was defined as the number of days the participant remained MMD seizure free after initiation of the treatment. The change from baseline in percentage of MMD seizure-free days, was defined as the percentage of seizure-free days during the Full Treatment Period minus the percentage of seizure-free days during the Baseline. A linear model with treatment group and age stratum as factors and baseline percentage as a covariate was used for analysis.

Trial Locations

Locations (98)

St. Christopher's Hospital for Children

🇺🇸

Philadelphia, Pennsylvania, United States

Seattle Children's Hospital

🇺🇸

Seattle, Washington, United States

Pecsi Tudomanyegyetem

🇭🇺

Pecs, Baranya, Hungary

Fondazione Policlinico Universitario A Gemelli

🇮🇹

Roma, Lazio, Italy

Stichting Epilepsie Instellingen Nederland

🇳🇱

Zwolle, Overijssel, Netherlands

Children and Youth Health Care Institute of Vojvodina

🇷🇸

Novi Sad, Serbia

NYU Comprehensive Epilepsy Center

🇺🇸

New York, New York, United States

Northwell Health Physician Partners - Neurology at Lenox Hill

🇺🇸

New York, New York, United States

Institute of Neurology and Neurosurgery at Saint Barnabas, LLC

🇺🇸

Livingston, New Jersey, United States

Pediatric Neurology PA

🇺🇸

Winter Park, Florida, United States

Center For Neurosciences

🇺🇸

Tucson, Arizona, United States

UZ Antwerpen PIN

🇧🇪

Edegem, Antwerpen, Belgium

Sydney Children's Hospital

🇦🇺

Randwick, New South Wales, Australia

Premier Healthcare Inc.

🇺🇸

New York, New York, United States

The Second Affiliated Hospital of Guangzhou Medical University

🇨🇳

Guangzhou, Guangdong, China

Midatlantic Epilepsy and Sleep Center

🇺🇸

Bethesda, Maryland, United States

Xiangya Hospital Central South University

🇨🇳

Changsha, Hunan, China

Austin Hospital

🇦🇺

Heidelberg, Victoria, Australia

Cook Children's Medical Center - Jane and John Justin Neurosciences Center

🇺🇸

Fort Worth, Texas, United States

Beijing Children's Hospital,Capital Medical University

🇨🇳

Beijing, Beijing, China

Hopital Universitaire des Enfants Reine Fabiola

🇧🇪

Brussels, Belgium

MultiCare Institute for Research & Innovation (Tacoma)

🇺🇸

Tacoma, Washington, United States

Child and Family Research Institute

🇨🇦

Vancouver, British Columbia, Canada

Peking University First Hospital

🇨🇳

Beijing, Beijing, China

Yasuhara Childrens Clinic

🇯🇵

Neyagawa-Shi, Osaka, Japan

Osaka City General Hospital

🇯🇵

Osaka-Shi, Osaka, Japan

Childrens University Hospital

🇱🇻

Riga, Latvia

Municipal Institution Dnipropetrovsk Regional Children Clinical Hospital of DRC

🇺🇦

Dnipro, Dnipropetrovs'ka Oblast, Ukraine

Communal Non-commercial Enterprise Iv-Frank Regional Childrens Clinical Hosp of Iv-Frank RC

🇺🇦

Ivano-Frankivsk, Ukraine

Hospital Regional Universitario de Malaga Hospital General

🇪🇸

Malaga, Spain

UGMK-Zdorojie, LLC

🇷🇺

Ekaterinburg, Russian Federation

National Center of Neurology and Psychiatry

🇯🇵

Kodaira-Shi, Tokyo, Japan

Hospital Universitario Vall d'Hebron - PPDS

🇪🇸

Barcelona, Spain

Fukuoka Children's Hospital

🇯🇵

Fukuoka-Shi, Hukuoka, Japan

Centro de Neurologia Avanzada

🇪🇸

Sevilla, Spain

Hospital Universitari i Politecnic La Fe de Valencia

🇪🇸

Valencia, Spain

Okayama University Hospital

🇯🇵

Okayama-city, Okayama, Japan

Aichi Medical University Hospital

🇯🇵

Nagakute-Shi, Aiti, Japan

ASST di Pavia - Fondazione Istituto Neurologico Mondino IRCCS

🇮🇹

Pavia, Lombardia, Italy

Phoenix Childrens Hospital

🇺🇸

Phoenix, Arizona, United States

University of California Benioff Children's Hospital

🇺🇸

San Francisco, California, United States

Oregon Health and Science University

🇺🇸

Portland, Oregon, United States

University of Utah - Primary Children's Hospital - PPDS

🇺🇸

Salt Lake City, Utah, United States

Children's Hospital Colorado.

🇺🇸

Denver, Colorado, United States

National Hospital Organization Shizuoka Institute of Epilepsy and Neurological Disorders

🇯🇵

Shizuoka-Shi, Sizuoka, Japan

Klinikum der Johann-Wolfgang Goethe-Universitat

🇩🇪

Frankfurt am Main, Hessen, Germany

WellSpan Oncology Research

🇺🇸

York, Pennsylvania, United States

David Geffen School of Medicine at UCLA

🇺🇸

Los Angeles, California, United States

Children's Hospital of Philadelphia

🇺🇸

Philadelphia, Pennsylvania, United States

Clinical Integrative Research Center of Atlanta

🇺🇸

Atlanta, Georgia, United States

Minnesota Epilepsy Group PA

🇺🇸

Roseville, Minnesota, United States

Medical University of South Carolina Children Hospital - PIN

🇺🇸

Charleston, South Carolina, United States

Queensland Childrens Hospital

🇦🇺

South Brisbane, Queensland, Australia

Hospital For Sick Children

🇨🇦

Toronto, Ontario, Canada

Alfred Hospital

🇦🇺

Melbourne, Victoria, Australia

Children's Hospital of Chongqing Medical University

🇨🇳

Chongqing, Chongqing, China

Shenzhen Children's Hospital

🇨🇳

Shenzhen, Guangdong, China

Wuhan Childrens hospital

🇨🇳

Wuhan, Hubei, China

Jiangxi Provincial Children's Hospital

🇨🇳

Nanchang, Jiangxi, China

Guangzhou Women And Children's Medical Center

🇨🇳

Guangzhou, Guangdong, China

The First Hospital of Jilin University

🇨🇳

Changchun, Jilin, China

CHRU Dijon Hopital General

🇫🇷

Dijon, Cote-d'Or, France

Children's Hospital of Shanghai

🇨🇳

Shanghai, Shanghai, China

Children's Hospital of Fudan University

🇨🇳

Shanghai, Shanghai, China

Hopital Roger Salengro

🇫🇷

Lille, Nord, France

Krankenhaus Mara gGmbH - Epilepsiezentrum Bethel

🇩🇪

Bielefeld, Nordrhein-Westfalen, Germany

Hopitaux de La Timone

🇫🇷

Marseille, France

Hopital Robert Debre

🇫🇷

Paris, France

Schon Klinik Vogtareuth

🇩🇪

Vogtareuth, Bayern, Germany

Hopital Necker - Enfants Malades

🇫🇷

Paris, France

Attikon University General Hospital

🇬🇷

Chaidari, Attiki, Greece

Kleinwachau Sachsisches Epilepsiezentrum Radeberg Gemeinnutzige Gmbh

🇩🇪

Radeberg, Sachse, Germany

University General Hospital of Larissa

🇬🇷

Larisa, Greece

Orszagos Mentalis, Ideggyogyaszati es Idegsebeszeti Intezet

🇭🇺

Budapest, Hungary

Bethesda Gyermekkorhaz

🇭🇺

Budapest, Hungary

Hippokration Hospital

🇬🇷

Thessaloniki, Greece

Szent Janos Korhaz es Eszak-Budai Egyesitett Korhazak

🇭🇺

Budapest, Hungary

Ospedale Bellaria

🇮🇹

Bologna, Emilia-Romagna, Italy

Azienda Ospedaliero Universitaria A Meyer - INCIPIT - PIN

🇮🇹

Firenze, Toscana, Italy

National Hospital Organization Nagasaki Medical Center

🇯🇵

Omura-Shi, Nagasaki, Japan

Kumamoto-Ezuko Medical Center for The Severely Disabled

🇯🇵

Kumamoto-Shi, Kumamoto, Japan

National Hospital Organization Nishi-Niigata Chuo National Hospital

🇯🇵

Niigata-Shi, Niigata, Japan

Osaka University Hospital

🇯🇵

Suita-Shi, Osaka, Japan

Kempenhaeghe - PPDS

🇳🇱

Heeze, Noord-Brabant, Netherlands

Szpital Kliniczny im. H.Swiecickiego Uniwersytetu Medycznego im. Karola Marcinkowskiego w Poznaniu

🇵🇱

Poznan, Poland

Uniwersyteckie Centrum Kliniczne

🇵🇱

Gdansk, Poland

Centrum Medyczne Plejady

🇵🇱

Krakow, Malopolskie, Poland

Clinic for Neurology and Psychiatry for Children and Youth

🇷🇸

Belgrade, Serbia

Mother and Child Health Care Institute of Serbia Dr Vukan Cupic

🇷🇸

Belgrade, Serbia

University Clinical Center Nis

🇷🇸

Nis, Serbia

Clinica Universidad Navarra

🇪🇸

Pamplona, Navarra, Spain

University of Iowa Hospitals & Clinics - (CRS)

🇺🇸

Iowa City, Iowa, United States

Centre Neurologique William Lennox

🇧🇪

Ottignies-Louvain-la-Neuve, Brabant Wallon, Belgium

CNPE Clinical Hospital Psychiatry of the Executive Body of the Kyiv City Council KCSA

🇺🇦

Kyiv, Ukraine

Communal Non-profit Enterprise City Childrens Clinical Hospital #6 of DCC

🇺🇦

Dnipro, Dnipropetrovs'ka Oblast, Ukraine

SI Ukr. Med. Rehabilitation Center For Children With Organic Injury of Nervous System of MoH of Ukr

🇺🇦

Kyiv, Ukraine

Alberta Childrens Hospital

🇨🇦

Calgary, Alberta, Canada

Thomas Jefferson University

🇺🇸

Philadelphia, Pennsylvania, United States

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