EpilepsyPhase 3EPIK-OLENCT04912856
An Open-Label Extension of the Study XEN496 (Ezogabine) in Children With KCNQ2-DEE
A Phase 3 study testing XEN496 in people with Epilepsy and Epilepsy in Children, run by Xenon Pharmaceuticals Inc. at 4 sites in 3 countries.
Trial summary
To assess the long-term safety and tolerability of XEN496 in pediatric subjects with KCNQ2 developmental and epileptic encephalopathy (KCNQ2-DEE) who had participated in the primary study (XPF-009-301). Read more about this study
- Who is it for?
- Ages 1 month to 6 years
- Conditions the study is for
- Epilepsy, Epilepsy in Children, Epilepsy; Seizure
- What is being tested?
- XEN496
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 8 participants
- Where
- 4 sitesin 3 countries
- Study dates
- 17 Aug 2021to 17 Nov 2023
- Phase
- Phase 3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 1 month to 6 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Subject completed participation in the primary study, XPF-009-301. A subject who withdraws from the primary study due to meeting protocol-specified worsening criteria will be considered as having completed participation in the primary study.
- The caregiver is willing and able to be compliant with diary completion, visit schedule, and study drug administration.
- Subject's caregiver achieved a minimum of 85% compliance with daily diary completion during both baseline and the double-blind period of the primary study.
Who cannot join
- Any adverse event(s) or serious adverse event(s) during the primary study XPF-009-301, which in the opinion of the investigator and sponsor's medical monitor, would preclude the subject's entry into the OLE study.
- A clinically significant condition or illness, or symptoms other than those resulting from KCNQ2-DEE, present at screening/baseline that, in the opinion of the investigator, would pose a risk to the subject if s/he were to enter the study.
- Any conditions that were specified as exclusion criteria in the primary study, XPF-009-301.
- It is anticipated that the subject will require treatment with at least 1 of the disallowed medications during the study.
- Any change in cardiac rhythm or atrioventricular conduction in the primary study that, in the investigator's opinion, is a significant risk to subject safety.
Trial locations and contacts
4 sites in 3 countries.
4 sites in 3 countries
United States2 sites
Children's Hospital of Philadelphia
Philadelphia, Pennsylvania, 19104
MultiCare Health System - Mary Bridge Pediatrics - Tacoma
Tacoma, Washington, 98405
Belgium1 site
Universitair Ziekenhuis Antwerpen - Dienst Kinderneurologie
Edegem, Antwerpen, 2650
About this study
Official title: An Open-Label Extension of the Study XEN496 in Children With KCNQ2 Developmental and Epileptic Encephalopathy
To assess the long-term safety and tolerability of XEN496 in pediatric subjects with KCNQ2 developmental and epileptic encephalopathy (KCNQ2-DEE) who had participated in the primary study (XPF-009-301).
Read the detailed description
This is an open-label, long-term extension study of XEN496 for the treatment of seizures in subjects with KCNQ2-DEE, that will be open to eligible subjects who participated in the primary study, XPF-009-301. The primary objective is to assess the long-term safety of XEN496. A double-blind transition/titration period will be used to maintain blinding to the treatment allocation in the primary study (XPF-009-301). After completion of the blinded transition/titration period, subjects will receive the open label study drug at their optimal dose for approximately 35 months.
- Conditions
- Epilepsy, Epilepsy in Children, Epilepsy; Seizure, Disease, Brain Diseases, Central Nervous System Diseases
- Being tested
- XEN496
- Keywords
- XEN496, Ezogabine, Retigabine, Encephalopathy, Seizure, KCNQ2, EPIK
- Medical subject headings
- Epilepsy, Disease, Brain Diseases, Central Nervous System Diseases, Nervous System Diseases, Epileptic Syndromes, Seizures
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
XEN496Drug
Also called ezogabine, retigabine
XEN496 sprinkle capsules. Parents / caregivers will be instructed to sprinkle and mix the contents of the capsules into soft foods or liquids and feed it to the child.
| Study group | Role | What they receive |
|---|---|---|
| Group 1: XEN496 only | Experimental | 24-day blinded transition/titration period. Subjects who received XEN496 in the preceding study will continue to receive XEN496 at the same dose, in a blinded manner, without any further titration. To maintain the blinded aspect of the study, placebo will be dispensed to all subjects during the transition/titration period to ensure the total number of capsules are consistent across all subjects.
Subjects who discontinue will be required to taper off study drug over a period of up to 15 days Receives: Drug: XEN496 |
| Group 2: Placebo to XEN496 | Experimental | 24-day blinded transition/titration period. Subjects who were allocated to placebo in the preceding study, will be titrated to a tolerated dose up to a maximum dose of 21 mg/kg/day, with a maximum daily dose of 672 mg/day. To maintain the blinded aspect of the study, placebo will be dispensed to all subjects during the transition/titration period to ensure the total number of capsules are consistent across all subjects
Subjects who discontinue or complete the study treatment will be required to taper off study drug over a period of up to 15 days. Receives: Drug: XEN496 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Adverse Events (AEs) and Serious Adverse Events (SAEs) Related to Intervention
Safety and tolerability of XEN496 as assessed by incidence and severity of AEs and SAEs
Measured: From Screening/Baseline through to 4 weeks post last dose
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Jun 2021
- Study start17 Aug 2021
- Primary completion17 Nov 2023
- Study completion17 Nov 2023
Why it stopped: Sponsor decision; not a safety decision
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for EpilepsyStudies of the same condition, open and under way.
- 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
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 8 participants (actual)
Sponsor and investigators
- Lead sponsor
- Xenon Pharmaceuticals Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Study Director, Study director, Xenon Pharmaceuticals Inc.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04912856
- Sponsor's protocol ID
- XPF-009-302
- Other IDs
- 2020-003447-28
- Acronym
- EPIK-OLE
- Status last verified
- Dec 2024
- First submitted
- 3 May 2021
- Last updated
- 14 Feb 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 14 Feb 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- An Open-Label Extension of the Study XEN496 in Children With KCNQ2 Developmental and Epileptic Encephalopathy
- ClinicalTrials.gov ID
- NCT04912856
- Acronym / sponsor ID
- EPIK-OLE / XPF-009-302
- Conditions
- Epilepsy, Epilepsy in Children, Epilepsy; Seizure, Disease, Brain Diseases, Central Nervous System Diseases
- Keywords
- XEN496, Ezogabine, Retigabine, Encephalopathy, Seizure, KCNQ2, EPIK
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Sponsor decision; not a safety decision
- Enrolment
- 8 participants (actual)
- Lead sponsor
- Xenon Pharmaceuticals Inc.Industry (pharma, biotech, devices)
- Study start
- 17 Aug 2021 (actual)
- Primary completion
- 17 Nov 2023 (actual)
- Study completion
- 17 Nov 2023 (actual)
- First posted
- 3 Jun 2021 (actual)
- Results
- Posted 14 Feb 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
To assess the long-term safety and tolerability of XEN496 in pediatric subjects with KCNQ2 developmental and epileptic encephalopathy (KCNQ2-DEE) who had participated in the primary study (XPF-009-301).
Detailed description
This is an open-label, long-term extension study of XEN496 for the treatment of seizures in subjects with KCNQ2-DEE, that will be open to eligible subjects who participated in the primary study, XPF-009-301. The primary objective is to assess the long-term safety of XEN496. A double-blind transition/titration period will be used to maintain blinding to the treatment allocation in the primary study (XPF-009-301). After completion of the blinded transition/titration period, subjects will receive the open label study drug at their optimal dose for approximately 35 months.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group 1: XEN496 only | Experimental | Drug: XEN49624-day blinded transition/titration period. Subjects who received XEN496 in the preceding study will continue to receive XEN496 at the same dose, in a blinded manner, without any further titration. To maintain the blinded aspect of the study, placebo will be dispensed to all subjects during the transition/titration period to ensure the total number of capsules are consistent across all subjects. Subjects who discontinue will be required to taper off study drug over a period of up to 15 days |
| Group 2: Placebo to XEN496 | Experimental | Drug: XEN49624-day blinded transition/titration period. Subjects who were allocated to placebo in the preceding study, will be titrated to a tolerated dose up to a maximum dose of 21 mg/kg/day, with a maximum daily dose of 672 mg/day. To maintain the blinded aspect of the study, placebo will be dispensed to all subjects during the transition/titration period to ensure the total number of capsules are consistent across all subjects Subjects who discontinue or complete the study treatment will be required to taper off study drug over a period of up to 15 days. |
Who may qualify
- Ages
- 1 month to 6 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (3 listed)
- Subject completed participation in the primary study, XPF-009-301. A subject who withdraws from the primary study due to meeting protocol-specified worsening criteria will be considered as having completed participation in the primary study.
- The caregiver is willing and able to be compliant with diary completion, visit schedule, and study drug administration.
- Subject's caregiver achieved a minimum of 85% compliance with daily diary completion during both baseline and the double-blind period of the primary study.
Key exclusion criteria (5 listed)
- Any adverse event(s) or serious adverse event(s) during the primary study XPF-009-301, which in the opinion of the investigator and sponsor's medical monitor, would preclude the subject's entry into the OLE study.
- A clinically significant condition or illness, or symptoms other than those resulting from KCNQ2-DEE, present at screening/baseline that, in the opinion of the investigator, would pose a risk to the subject if s/he were to enter the study.
- Any conditions that were specified as exclusion criteria in the primary study, XPF-009-301.
- It is anticipated that the subject will require treatment with at least 1 of the disallowed medications during the study.
- Any change in cardiac rhythm or atrioventricular conduction in the primary study that, in the investigator's opinion, is a significant risk to subject safety.
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 |
|---|---|---|
| XEN496Also: ezogabine, retigabineXEN496 sprinkle capsules. Parents / caregivers will be instructed to sprinkle and mix the contents of the capsules into soft foods or liquids and feed it to the child. | Drug | Group 1: XEN496 only, Group 2: Placebo to XEN496 |
Primary outcome
Incidence of Adverse Events (AEs) and Serious Adverse Events (SAEs) Related to Intervention
Time frame: From Screening/Baseline through to 4 weeks post last dose
Safety and tolerability of XEN496 as assessed by incidence and severity of AEs and SAEs
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Feb 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- XPF-009-301 Study (EPIK)Link provided by the sponsor.
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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. This study is not recruiting at the moment.
Study Director study director
Xenon Pharmaceuticals Inc.
4 sites in 3 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing XEN496 in people with Epilepsy and Epilepsy in Children, run by Xenon Pharmaceuticals Inc. at 4 sites in 3 countries.
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 3 inclusion and 5 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: stopped early, as of the sponsor's last update on 14 Feb 2025. 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 United States, Australia, Belgium. 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.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 14 Feb 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Adverse Events (AEs) and Serious Adverse Events (SAEs) Related to Intervention (time frame: From Screening/Baseline through to 4 weeks post last dose). 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 14 Feb 2025; AzTrials last refreshed its copy on 8 Nov 2026.