Developmental and Epileptic EncephalopathyEEPILOGNCT07396883
Developmental and Epileptic Encephalopathies Diagnosed Via Long-read Genome Sequencing
An observational study of Developmental and Epileptic Encephalopathy and Epilepsy in Children, run by University Hospital, Strasbourg, France at 4 sites in France.
Trial summary
This study focuses on children with Developmental and Epileptic Encephalopathy (DEE), a severe form of epilepsy that often has a genetic origin. Currently, standard diagnostic tools-known as short-read genome sequencing-fail to provide a diagnosis for over 50% of affected patients because they cannot detect certain… Read more about this study
- Who is it for?
- Ages Up to 18 years
- Conditions the study is for
- Developmental and Epileptic Encephalopathy, Epilepsy in Children
- What is being tested?
- Long-read Whole Genome Sequencing (lrWGS)
- How many people
- 20 participants
- Where
- 4 sitesFrance
- Study dates
- Jun 2026to Jun 2028
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Up to 18 years
- All sexes
- No healthy volunteers
- Child, Adult
Study population: The study population is drawn from specialized pediatric neurology and genetics departments within the French university hospital network (CHU). Participants are specifically sourced from the existing patient base of the AURAGEN platform, one of the two national sequencing hubs established under the French Genomic Medicine Plan 2025 (PFMG 2025). These individuals represent a highly selected sub-population of children across France who have already undergone extensive clinical phenotyping and "first-line" genomic screening but remain without a molecular diagnosis. The recruitment occurs primarily at the Strasbourg University Hospital (Hôpitaux Universitaires de Strasbourg) and collaborating clinical sites. These centers serve as regional and national referral points for rare and refractory childhood epilepsies, ensuring that the study population includes the most complex and diagnostically challenging cases of Developmental and Epileptic Encephalopathy (DEE) in the country.
Who may be able to join
- Pediatric Participants:
- Age < 18 years.
- Diagnosis of Developmental and Epileptic Encephalopathy (DEE) according to 2022 ILAE criteria (severe epilepsy, encephalopathic EEG, multiple drug-resistant seizures, and neurodevelopmental disorder).
- Brain MRI without markers of perinatal anoxia.
- Negative molecular diagnosis after short-read Whole Genome Sequencing (srWGS) via the French Genomic Medicine Plan 2025 (AURAGEN).
- Available banked DNA at a participating center.
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- Parents/Legal Guardians:
- Age ≥ 18 years.
- Able to understand study objectives and risks.
- Signed and dated informed consent.
- Affiliated with or beneficiary of a social security scheme.
Who cannot join
- Pediatric Participants:
- Brain MRI findings in favor of perinatal cerebral anoxia.
- Intercurrent diseases preventing the completion of protocol examinations.
- Subject currently in an exclusion period from another study.
- Parents/Legal Guardians:
- Inability to receive or understand informed information (e.g., life-threatening emergency).
- Subject under judicial protection, tutelage, or curatorship.
- Language barriers where an official interpreter is unavailable.
Trial locations and contacts
4 sites in 1 country. Contact the study team or a site near you to ask about taking part.
France4 sites
CHU Jean Minjoz
Besançon, 25000
Joanna BELLEVILLE, +333.81.21.81.46 ext. +33, jgoffeney@chu-besancon.fr
American Memorial Hospital
Reims, 51092
Mélanie JENNESON, +333.26.78.78.99 ext. +33, Mjennesson-lyver@chu-reims.fr
Hôpitaux Universitaires de Strasbourg
Strasbourg, 67098
Sarah BAER, +333.88.12.84.98 ext. +33, sarah.baer@chru-strasbourg.fr
CHU de Nancy - hôpital d'enfant
Vandœuvre-lès-Nancy, 54511
Mathieu KUCHENBUCH, +333.83.15.50.85 ext. +33, m.kuchenbuch@chru-nancy.fr
About this study
Official title: Developmental and Epileptic Encephalopathies Diagnosed Via Long-read Genome Sequencing - EEPILOG
This study focuses on children with Developmental and Epileptic Encephalopathy (DEE), a severe form of epilepsy that often has a genetic origin. Currently, standard diagnostic tools-known as short-read genome sequencing-fail to provide a diagnosis for over 50% of affected patients because they cannot detect certain complex DNA abnormalities.
The purpose of this study is to evaluate the effectiveness of a newer, more advanced technology called Long-read Genome Sequencing (lrWGS). Unlike traditional methods, this technology analyzes very long fragments of DNA, allowing researchers to identify genetic errors that were previously "invisible."
The study aims to answer whether Long-read Sequencing can successfully identify the genetic cause of epilepsy in patients who have already received a negative result from standard testing. By finding these missing answers, the research seeks to enable personalized medical treatments, improve genetic counseling for families, and advance our understanding of how these complex neurological conditions develop.
Read the detailed description
This study evaluates the clinical utility of Long-read Whole Genome Sequencing (lrWGS) as a secondary diagnostic tool for Developmental and Epileptic Encephalopathies (DEEs). While current standard-of-care "short-read" sequencing (srWGS) is effective at identifying small genetic mutations, it often fails to detect complex structural changes, leaving over 50% of patients without a diagnosis.
Technically, lrWGS overcomes these limitations by analyzing DNA fragments that are thousands of bases long. This allows researchers to map "dark regions" of the genome and identify Structural Variants (SVs), such as large insertions, deletions, or repeat expansions, which are often the hidden causes of severe epilepsy.
By identifying these elusive genetic drivers, the study aims to move beyond a simple diagnosis toward precision medicine. A clear molecular result can directly influence clinical decisions, such as selecting targeted medications, avoiding contraindicated drugs, or determining eligibility for emerging gene therapies. Additionally, the project assesses the feasibility of integrating this technology into routine clinical practice by evaluating bioinformatic complexity and diagnostic turnaround times.
- Being tested
- Long-read Whole Genome Sequencing (lrWGS)
- Keywords
- Developmental and Epileptic Encephalopathy (DEE), Drug-Resistant Epilepsy, Long-read Whole Genome Sequencing (lrWGS), Long-read Sequencing, Negative Short-read Sequencing, Genetic Diagnosis, Pediatric Neurology, High-Throughput Nucleotide Sequencing, Early-Onset Epilepsy, Genetic Epilepsy
- Medical subject headings
- Drug Resistant Epilepsy
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Long-read Whole Genome Sequencing (lrWGS)Diagnostic test
Long-read Whole Genome Sequencing (lrWGS) using high-molecular-weight DNA previously extracted and banked during the patient's initial clinical workup.
| Study group | Role | What they receive |
|---|---|---|
| DEE Long-read | his cohort is composed of pediatric patients (under 18 years old) with Developmental and Epileptic Encephalopathy (DEE) as defined by the 2022 ILAE criteria.
The group is specifically characterized by a prior negative molecular diagnosis despite analysis via short-read Whole Genome Sequencing (srWGS) through the French Genomic Medicine Plan 2025 (AURAGEN platform).
Selection follows a clinical prioritization strategy: while the study includes all eligible DEE patients without a genetic answer, priority is given to those with early-onset forms, familial cases, or current therapeutic impasse (patients for whom standard treatments have failed). The study excludes cases where a clear non-genetic cause is identified, such as perinatal brain injury, focusing the cohort on high-probability "hidden" genetic etiologies. Receives: Diagnostic Test: Long-read Whole Genome Sequencing (lrWGS) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of pathogenic and likely pathogenic genetic variants identified by long-read whole genome sequencing (lrWGS)
Evaluate the efficacy of long-read whole genome sequencing (lrWGS) in identifying genetic causes in patients with developmental and epileptic encephalopathy who did not obtain a molecular diagnosis despite previous short-read whole genome sequencing (srWGS) analysis within the framework of the French Genomic Medicine Plan 2025 (PFMG 2025).
Measured: At the results delivery visit (Visit 1), up to 15 months after enrollment.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Feb 2026
- Study startJun 2026 (estimated)
- Primary completionJun 2028 (estimated)
- Study completionJun 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Developmental and Epileptic EncephalopathyStudies of the same condition, open and under way.
- More trials run by University Hospital, Strasbourg, FranceThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case only
- Time perspective
- Prospective
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Hospital, Strasbourg, France
- Sponsor type
- University, hospital or other
- Collaborators
- IGBMC, Laboratoire de diagnostic génétique - NHC, Groupe Méthode en Recherche Clinique (GMRC), Bio-informatique médicale appliquée au diagnostic (UF7363) - NHC
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07396883
- Sponsor's protocol ID
- 9964
- Acronym
- EEPILOG
- Status last verified
- Feb 2026
- First submitted
- 2 Feb 2026
- Last updated
- 9 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 9 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Developmental and Epileptic Encephalopathies Diagnosed Via Long-read Genome Sequencing - EEPILOG
- ClinicalTrials.gov ID
- NCT07396883
- Acronym / sponsor ID
- EEPILOG / 9964
- Keywords
- Developmental and Epileptic Encephalopathy (DEE), Drug-Resistant Epilepsy, Long-read Whole Genome Sequencing (lrWGS), Long-read Sequencing, Negative Short-read Sequencing, Genetic Diagnosis, Pediatric Neurology, High-Throughput Nucleotide Sequencing
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 20 participants (estimated)
- Lead sponsor
- University Hospital, Strasbourg, FranceUniversity, hospital or other
- Collaborators
- IGBMC, Laboratoire de diagnostic génétique - NHC, Groupe Méthode en Recherche Clinique (GMRC), Bio-informatique médicale appliquée au diagnostic (UF7363) - NHC
- Study start
- Jun 2026 (estimated)
- Primary completion
- Jun 2028 (estimated)
- Study completion
- Jun 2028 (estimated)
- First posted
- 9 Feb 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study focuses on children with Developmental and Epileptic Encephalopathy (DEE), a severe form of epilepsy that often has a genetic origin. Currently, standard diagnostic tools-known as short-read genome sequencing-fail to provide a diagnosis for over 50% of affected patients because they cannot detect certain complex DNA abnormalities.
The purpose of this study is to evaluate the effectiveness of a newer, more advanced technology called Long-read Genome Sequencing (lrWGS). Unlike traditional methods, this technology analyzes very long fragments of DNA, allowing researchers to identify genetic errors that were previously "invisible."
The study aims to answer whether Long-read Sequencing can successfully identify the genetic cause of epilepsy in patients who have already received a negative result from standard testing. By finding these missing answers, the research seeks to enable personalized medical treatments, improve genetic counseling for families, and advance our understanding of how these complex neurological conditions develop.
Detailed description
This study evaluates the clinical utility of Long-read Whole Genome Sequencing (lrWGS) as a secondary diagnostic tool for Developmental and Epileptic Encephalopathies (DEEs). While current standard-of-care "short-read" sequencing (srWGS) is effective at identifying small genetic mutations, it often fails to detect complex structural changes, leaving over 50% of patients without a diagnosis.
Technically, lrWGS overcomes these limitations by analyzing DNA fragments that are thousands of bases long. This allows researchers to map "dark regions" of the genome and identify Structural Variants (SVs), such as large insertions, deletions, or repeat expansions, which are often the hidden causes of severe epilepsy.
By identifying these elusive genetic drivers, the study aims to move beyond a simple diagnosis toward precision medicine. A clear molecular result can directly influence clinical decisions, such as selecting targeted medications, avoiding contraindicated drugs, or determining eligibility for emerging gene therapies. Additionally, the project assesses the feasibility of integrating this technology into routine clinical practice by evaluating bioinformatic complexity and diagnostic turnaround times.
Study design
- Observational model
- Case only
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| DEE Long-read | – | Diagnostic Test: Long-read Whole Genome Sequencing (lrWGS)his cohort is composed of pediatric patients (under 18 years old) with Developmental and Epileptic Encephalopathy (DEE) as defined by the 2022 ILAE criteria. The group is specifically characterized by a prior negative molecular diagnosis despite analysis via short-read Whole Genome Sequencing (srWGS) through the French Genomic Medicine Plan 2025 (AURAGEN platform). Selection follows a clinical prioritization strategy: while the study includes all eligible DEE patients without a genetic answer, priority is given to those with early-onset forms, familial cases, or current therapeutic impasse (patients for whom standard treatments have failed). The study excludes cases where a clear non-genetic cause is identified, such as perinatal brain injury, focusing the cohort on high-probability "hidden" genetic etiologies. |
Who may qualify
- Ages
- Up to 18 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
- Study population
- The study population is drawn from specialized pediatric neurology and genetics departments within the French university hospital network (CHU). Participants are specifically sourced from the existing patient base of the AURAGEN platform, one of the two national sequencing hubs established under the French Genomic Medicine Plan 2025 (PFMG 2025). These individuals represent a highly selected sub-population of children across France who have already undergone extensive clinical phenotyping and "first-line" genomic screening but remain without a molecular diagnosis. The recruitment occurs primarily at the Strasbourg University Hospital (Hôpitaux Universitaires de Strasbourg) and collaborating clinical sites. These centers serve as regional and national referral points for rare and refractory childhood epilepsies, ensuring that the study population includes the most complex and diagnostically challenging cases of Developmental and Epileptic Encephalopathy (DEE) in the country.
Key inclusion criteria (11 listed)
- Age < 18 years.
- Diagnosis of Developmental and Epileptic Encephalopathy (DEE) according to 2022 ILAE criteria (severe epilepsy, encephalopathic EEG, multiple drug-resistant seizures, and neurodevelopmental disorder).
- Brain MRI without markers of perinatal anoxia.
- Negative molecular diagnosis after short-read Whole Genome Sequencing (srWGS) via the French Genomic Medicine Plan 2025 (AURAGEN).
- Available banked DNA at a participating center.
Key exclusion criteria (8 listed)
- Brain MRI findings in favor of perinatal cerebral anoxia.
- Intercurrent diseases preventing the completion of protocol examinations.
- Subject currently in an exclusion period from another study.
- Inability to receive or understand informed information (e.g., life-threatening emergency).
- Subject under judicial protection, tutelage, or curatorship.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Long-read Whole Genome Sequencing (lrWGS)Long-read Whole Genome Sequencing (lrWGS) using high-molecular-weight DNA previously extracted and banked during the patient's initial clinical workup. | Diagnostic test | DEE Long-read |
Primary outcome
Number of pathogenic and likely pathogenic genetic variants identified by long-read whole genome sequencing (lrWGS)
Time frame: At the results delivery visit (Visit 1), up to 15 months after enrollment.
Evaluate the efficacy of long-read whole genome sequencing (lrWGS) in identifying genetic causes in patients with developmental and epileptic encephalopathy who did not obtain a molecular diagnosis despite previous short-read whole genome sequencing (srWGS) analysis within the framework of the French Genomic Medicine Plan 2025 (PFMG 2025).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Feb 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
4 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Developmental and Epileptic Encephalopathy and Epilepsy in Children, run by University Hospital, Strasbourg, France at 4 sites in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 11 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 9 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Sarah BAER (+333.88.12.84.98 ext. +33, sarah.baer@chru-strasbourg.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of pathogenic and likely pathogenic genetic variants identified by long-read whole genome sequencing (lrWGS) (time frame: At the results delivery visit (Visit 1), up to 15 months after enrollment.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Feb 2026.