A Study on Dravet Syndrome (DS) and Lennox-Gastaut Syndrome (LGS) in Children, Teenagers and Adults in Portugal (DRALEGA-PT)

Epidemiology of Dravet and Lennox-Gastaut Syndromes in Portugal

The main aim of this study is to learn about the percentage of persons diagnosed with Dravet Syndrome (DS) and Lennox-Gastaut-Syndrome (LGS) in 2022 and of persons newly diagnosed in 2021 and 2022 compared to the overall population in Portugal. Other aims are to understand how many percent of the persons diagnosed with DS and LGS are children, teenagers or adults and gather additional information on diagnosis and persons diagnosed with DS and LGS in Portugal.

Information will be taken from a participant's existing medical hospital records. It is planned to review data in approximately 3 public hospitals in Portugal. No personal information of the participants will be collected.

Study Overview

• Status: Withdrawn
• Conditions: Dravet Syndrome (DS); Lennox-Gastaut Syndrome (LGS)
• Intervention / Treatment: Other: No Intervention

Detailed Description

This is a non-interventional, multicentre, cross-sectional retrospective study of participants from Portugal with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) at public hospitals. The participants will be identified from their medical charts or hospital records and those who meet the eligibility criteria will be included.

This multi-center trial will be conducted in Portugal. Data will be retrospectively collected for the observation period between 01 January 2021 to 31 December 2022. The total duration of the study is approximately 24 months.

• Study Type: Observational

Contacts and Locations

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Participants diagnosed with DS or LGS at public hospitals in Portugal will be enrolled in the study.

Description

Inclusion Criteria:

1. Diagnosis criteria for DS:

   • All the following criteria must be met: i. Seizures onset within 1-20 months (usually within the first year of life). ii. Normal initial development prior to presentation (no cognitive or behavioural disability before the onset of seizures) followed by behaviour and cognitive impairment.

   iii. Recurrent focal clonic (hemiclonic) febrile and afebrile seizures (which often alternate sides from seizure to seizure), focal to bilateral tonic-clonic, and/or generalized clonic seizures.

   • And at least one of the following criteria must be met: i. Emergence of other seizure type, including atypical absence seizures, myoclonic seizures, atonic seizures, or non-tonic-clonic status epilepticus between 1-4 years.

   ii. Seizures triggered by fever due to illness or vaccinations, hot baths, sudden temperature changes, high level of activity, or by strong lighting or exposure to certain visual patterns.

   iii. Mutations or copy number variants in the SCN1A gene.

2. Diagnosis criteria for LGS:

Given the uncertainties associated with the diagnosis of this condition, two different criteria will be used, a stricter criterion, intended to identify "pure" Lennox-Gastaut syndrome participants, and a wider criterion, intended to also include the so-called Lennox-Gastaut-like participants.

Lennox-Gastaut syndrome - stricter criteria:

• All the following criteria must be met: i. Seizures onset before 18 years of age, typically from 1 to 8 years. ii. Progressive development/cognition impairment after seizures onset. iii. Tonic seizures. iv. At least one additional seizure: generalised tonic-clonic seizures, atypical absence seizures, atonic seizures, myoclonic seizures, focal impaired awareness, epileptic spams, or non-convulsive status epilepticus v. Slow (less thank [<] 2.5 hertz [Hz]) spike-and-wave EEG pattern. vi. Paroxysmal fast activity (10 Hz or greater) in sleep.

Lennox-Gastaut syndrome - wider criteria:

• At least one the following criteria must be met:

  i. Tonic seizures. ii. Multiple types of seizures, including generalised tonic-clonic seizures, atypical absence seizures, atonic seizures, myoclonic seizures, myoclonic-atonic seizures, focal seizures, epileptic spams, or nonconvulsive status epilepticus.

• And at least one the following criteria must be met:

  i. Slow (<2.5 Hz) spike-and-wave EEG pattern. ii. Paroxysmal fast activity (10 Hz or greater) in sleep.

• And at least two of the following criteria must be met:

  i. Seizures onset before 18 years of age, typically from 1 to 8 years. ii. Progressive development/cognition impairment after seizures onset. iii. Development/cognition impairment starts prior to seizures onset. iv. History of Infantile epileptic spasms syndrome (IESS), West or Ohtahara syndromes.

Exclusion Criteria

1. Has epileptic condition other than DS or LGS.
2. Has DS or LGS not residents in the reference area of the hospital.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Participants With DS or LGS; Participants with a medical record of diagnosis with either DS or LGS that are treated in the participating hospitals and reside in the reference area of these hospitals will be included and data will be retrospectively collected for the period between 01 January 2021 to 31 December 2022.	Other: No Intervention; As this is an observational study, no intervention will be administered.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
One-Year Period Prevalence of DS	Number of participants with DS over a period of one year will be assessed.	Up to 12 months
One-Year Period Prevalence of LGS Based on Stricter Diagnosis Criterion	Number of participants with LGS over a period of one year based on stricter diagnosis criterion will be assessed.	Up to 12 months
Incidence of DS	Number of participants diagnosed annually with DS yearly.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Incidence of LGS Based on Stricter Diagnosis Criterion	Number of participants diagnosed annually with LGS based on stricter diagnosis criterion.	At two different 12 months periods (in consecutive years at Months 12 and 24)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
One-Year Period Prevalence of LGS Based on Wider Diagnosis Criterion	Number of participants with LGS over a period of one year based on wider diagnosis criterion will be assessed.	Up to 12 months
One-Year Period Prevalence of Paediatric DS	Number of participants with paediatric DS over a period of one year will be assessed.	Up to 12 months
One-Year Period Prevalence of Paediatric LGS Based on Stricter and Wider Diagnoses Criteria	Number of participants with paediatric LGS over a period of one year based on stricter and wider diagnoses criteria will be assessed.	Up to 12 months
One-Year Period Prevalence of Adult DS	Number of participants with adult DS over a period of one year will be assessed.	Up to 12 months
One-Year Period Prevalence of Adult LGS Based on Stricter and Wider Diagnoses Criteria	Number of participants with adult LGS over period of one year based on stricter and wider diagnoses criteria will be assessed.	Up to 12 months
Incidence of LGS Based on Wider Diagnosis Criterion	Number of participants diagnosed annually with LGS based on wider diagnosis criterion.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Incidence of Paediatric DS	Number of paediatric participants diagnosed annually with DS.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Incidence of Paediatric LGS Based on Stricter and Wider Diagnoses Criteria	Number of paediatric participants diagnosed annually with LGS based on stricter and wider diagnoses criteria.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Incidence of Adult DS	Number of adult participants diagnosed annually with DS.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Incidence of Adult LGS Based on Stricter and Wider Diagnoses Criteria	Number of adult participants diagnosed annually with LGS based on stricter and wider diagnoses criteria.	At two different 12 months periods (in consecutive years at Months 12 and 24)
DS Categorized Based on Gender Distribution	DS categorized participants based on gender distribution will be assessed.	Up to 12 months
LGS Categorized Based on Gender Distribution According to Stricter and Wider Diagnoses Criteria	LGS categorized participants based on gender distribution according to Stricter and Wider diagnoses criteria will be assessed.	Up to 12 months
DS Categorized Based on Age Distribution	DS categorized participants based on age distribution will be assessed.	Up to 12 months
LGS Categorized Based on Age Distribution According to Stricter and Wider Diagnoses Criteria	LGS categorized participants based on age distribution according to Stricter and Wider diagnoses criteria will be assessed.	Up to 12 months
DS Categorized Based on Gender Distribution at Diagnosis	Annually diagnosed DS participants will be categorized based on gender distribution at diagnosis.	At two different 12 months periods (in consecutive years at Months 12 and 24)
LGS Categorized Based on Gender Distribution at Diagnosis According to Stricter and Wider Diagnoses Criteria	Annually diagnosed LGS participants will be categorized based on gender distribution at diagnosis.	At two different 12 months periods (in consecutive years at Months 12 and 24)
DS Categorized Based on Age Distribution at Diagnosis	Annually diagnosed DS participants will be categorized based on age distribution at diagnosis.	At two different 12 months periods (in consecutive years at Months 12 and 24)
LGS Categorized Based on Age Distribution at Diagnosis According to Stricter and Wider Diagnoses Criteria	Annually diagnosed LGS participants will be categorized based on age distribution at diagnosis.	At two different 12 months periods (in consecutive years at Months 12 and 24)
DS Categorized Based on Gender Distribution at Symptoms Onset	Annually diagnosed DS participants will be categorized based on gender distribution at symptoms onset.	At two different 12 months periods (in consecutive years at Months 12 and 24)
LGS Categorized Based on Gender Distribution at Symptoms Onset According to Stricter and Wider Diagnoses Criteria	Annually diagnosed LGS participants will be categorized based on gender distribution at symptoms onset.	At two different 12 months periods (in consecutive years at Months 12 and 24)
DS Categorized Based on Age Distribution at Symptoms Onset	Annually diagnosed DS participants will be categorized based on age distribution at symptoms onset.	At two different 12 months periods (in consecutive years at Months 12 and 24)
LGS Categorized Based on Age Distribution at Symptoms Onset According to Stricter and Wider Diagnoses Criteria	Annually diagnosed LGS participants will be categorized based on age distribution at symptoms onset.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Diagnosis Delay for Participants With DS	Diagnosis delay is defined as time from symptoms onset to diagnosis.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Diagnosis Delay for Participants With LGS Based on Stricter and Wider Diagnoses Criteria	Diagnosis delay is defined as time from tonic seizures onset to electroencephalography (EEG) confirmation.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Participants With DS: Ratio of Participants Genetically and Clinically Diagnosed Versus Participants Clinically Diagnosed Only	Participants with DS: ratio of participants genetically (Sodium Channel Protein Type 1 Subunit Alpha [SCN1A] Mutation) and clinically diagnosed versus participants clinically diagnosed only will be assessed.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Participants With LGS: Number of Participants Distributed According to Aetiologies Based on Stricter and Wider Diagnoses Criteria	Participants with LGS: number of participants distributed according to aetiologies based on Stricter and Wider Diagnoses Criteria will be assessed.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Participants With DS: Number of Participants With Different Types of Comorbidities at Diagnosis	Participants with DS: number of participants with different types of comorbidities at diagnosis will be assessed.	At two different 12 months periods (in consecutive years at Months 12 and 24)
Participants With LGS: Number of Participants With Different Types of Comorbidities at Diagnosis Based on Stricter and Wider Diagnoses Criteria	Number of participants with different types of comorbidities at diagnosis based on Stricter and Wider Diagnoses Criteria will be assessed.	At two different 12 months periods (in consecutive years at Months 12 and 24)

Collaborators and Investigators

• Sponsor: Takeda
• Investigators: Study Director: Study Director, Takeda

Publications and helpful links

Helpful Links

• To obtain more information on the study, click this link.

Study record dates

Study Major Dates

• Study Start (Estimated): December 1, 2024
• Primary Completion (Estimated): July 1, 2025
• Study Completion (Estimated): July 1, 2025

Study Registration Dates

• First Submitted: April 29, 2024
• First Submitted That Met QC Criteria: April 29, 2024
• First Posted (Actual): May 2, 2024

Study Record Updates

• Last Update Posted (Actual): October 3, 2024
• Last Update Submitted That Met QC Criteria: October 1, 2024
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Keywords: Drug Therapy
• Additional Relevant MeSH Terms: Pathologic Processes; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy, Generalized; Epileptic Syndromes; Disease; Genetic Diseases, Inborn; Epilepsy; Epilepsies, Myoclonic; Syndrome; Lennox Gastaut Syndrome
• Other Study ID Numbers: TAK-935-5004

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.
• IPD Sharing Access Criteria: IPD from eligible studies will be shared with qualified researchers according to the criteria and process described on https://vivli.org/ourmember/takeda/. For approved requests, the researchers will be provided access to anonymized data (to respect patient privacy in line with applicable laws and regulations) and with information necessary to address the research objectives under the terms of a data sharing agreement.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No