Section 3 of 6
Product information and disease description
88 evidence topics · 63 sources
Product description
Phase of product development
Regulatory submission: NDA submitted in early 2026
Updated regulatory timeline
Additional clinical studies
Review extension: additional analyses
Breakthrough Therapy designation announcement
FDA orphan designation: SCN8A
| Information | Quoted record |
|---|---|
| Date designated | “04/08/2021” |
| Orphan designation | “Treatment of SCN8A Developmental and Epileptic Encephalopathy” |
| FDA orphan approval status | “Not FDA Approved for Orphan Indication” |
Launch
No evidence found.
Product information
Generic, brand name and therapeutic class of product
Manufacturer: Praxis Precision Medicines
| Field | Quoted record |
|---|---|
| Sponsor | “Praxis Precision Medicines, Inc.” |
Dosage forms and strengths
Formulation and administration: manufacturer presentation
Clinical product formulation: material safety data sheet
No evidence found.
Formulation strength
No evidence found.
Average sales price and wholesale acquisition cost
Product price and anticipated annual cost per patient
Not applicable.
American hospital formulary service (AHFS), or other drug classification
Mechanistic classification
AHFS classification
No evidence found.
Indication
Indication under regulatory review
Pharmacology
Mechanism of action
Proposed mechanism of action
Pharmacodynamics
Pharmacokinetics
Pharmacokinetics and food effect: PRAX-562-101 healthy-volunteer study
Pharmacokinetics and metabolism: EILAT XVIII progress report
Contraindications/Warnings/Precautions/Adverse effects
Warnings and precautions
FDA-approved prescribing information, contraindications, boxed warnings, and REMS
Not applicable.
Special populations
Pediatric trial population: EMBOLD cohort 1
Healthy-adult pharmacokinetic population
Renal impairment, hepatic impairment, pregnancy, and lactation
No evidence found.
Drug/Drug, drug/disease interactions
Effects of other drugs on Relutrigine
Ciprofloxacin coadministration: increased relutrigine exposure
Effects of Relutrigine on other drugs
Relutrigine 120 mg once daily: enzyme inhibition
Dosing and administration
Dosage
Administration
Administration routes: manufacturer presentation
Administration with food: healthy-volunteer study
Access and distribution
Anticipated patient support
Co-prescribed/Concomitant therapies
EMBOLD cohort 2: baseline medication use among relutrigine-exposed participants
| Baseline ASMs | Participants |
|---|---|
| 1 to 2 | “17 (33%)” |
| 3 to 6 | “34 (67%)” |
Effect of Relutrigine on quality measures
No evidence found.
Product comparison
Direct clinical comparison with another active antiseizure medication
No evidence found.
Place of product in therapy
Disease description
Definition and etiology
SCN2A-associated epilepsy: inheritance
Epidemiology
Incidence of SCN2A- and SCN8A-related developmental and epileptic encephalopathies
SCN8A-related disorders: Danish birth-cohort frequency
SCN2A-related epilepsy: estimated Danish incidence, broader than DEE
Prevalence of SCN2A- and SCN8A-related developmental and epileptic encephalopathies
Epidemiology: combined SCN2A and SCN8A population, manufacturer estimate
Epidemiology: SCN8A-related epilepsy and neurodevelopmental disorders
Natural history, survival, and mortality
SCN2A-associated epilepsy: onset
Natural history of SCN8A-related disorders
Pathophysiology
Clinical phenotype spectrum and variant function in SCN2A-related disorders
Diagnosis
Diagnostic genetic testing of the epilepsies
Clinical presentation - signs and symptoms
Neurological symptoms: seizures, encephalopathy, and intellectual disability
Long-term morbidity
Development and adaptive function in SCN2A-related disorders
Seizure control across SCN8A phenotypes: consensus publication
Burden of SCN2A- and SCN8A-related developmental and epileptic encephalopathies
Humanistic burden and health-related quality of life
Literature review: impact of developmental and epileptic encephalopathies on caregivers
German burden-of-illness study: quality-of-life outcomes
SCN2A-related disorders: trial-readiness for non-seizure outcomes
SCN2A-related disorders: level of adaptive functioning and change over time
SCN2A-related disorders: implications for choosing trial endpoints
SCN2A-related disorders: gross motor function
SCN2A-related disorders: Vineland-3 growth scale values
SCN2A-related disorders: goal attainment scaling pilot study
Severe neurodevelopmental impairments: meaningful change
SCN8A-related disorders: quality of life and adaptive functioning
SCN8A-related disorders: quality of life and adaptive function by epilepsy phenotype
SCN8A-related epilepsy: associations with quality of life and adaptive functioning
Genetic developmental and epileptic encephalopathies: caregiver assessment of quality of life
Severe neurodevelopmental disorders: caregiver-reported quality of life
Genetic developmental and epileptic encephalopathies: non-seizure outcomes and caregiver priorities
SCN8A caregiver priorities: research-roadmap publication
Economic burden and healthcare resource utilization
Existing treatment burden: SCN8A caregiver survey
SCN2A-related disorders: medical-record study
SCN8A-related disorders: medical-record study
German burden-of-illness study: registry recruitment status
German burden-of-illness study: economic outcomes
Economic impact of SCN2A- and SCN8A-related developmental and epileptic encephalopathies on families
No evidence found.
Economic impact of diagnostic testing
UK neonatal epilepsy: earlier gene-panel testing, not relutrigine-specific
Approaches to treatment
Current treatment options and standard of care
Sodium channel blockers
SCN8A-related epilepsy and neurodevelopmental disorders: global modified Delphi consensus
SCN2A gain-of-function phenotype: antiseizure medication regimen
SCN8A-related disorders: cenobamate as add-on treatment
SCN8A cenobamate evidence: study design
Benzodiazepines
SCN8A status epilepticus: phenytoin and fosphenytoin after first-line benzodiazepines
Other antiseizure medications
SCN2A later-onset DEE: differential response compared with early-onset DEE
Corticosteroids and immunoglobulins
SCN8A: corticosteroids and immunoglobulins when standard ASMs are ineffective
Ketogenic dietary therapy
SCN8A: modified Delphi consensus
Vagus nerve stimulation
SCN8A: vagus nerve stimulation when standard ASMs are ineffective
Cannabinoids
SCN8A: cannabinoids when standard ASMs are ineffective
Developmental and supportive therapies
SCN8A: multidisciplinary treatment and early referral
Limitations of current therapies
Summary
Current treatment is heterogeneous and frequently involves several antiseizure medications. The SCN8A caregiver survey found that 77% were taking at least two ASMs and 50% had tried and stopped at least four. Sodium channel blocker recommendations depend on variant function and phenotype: consensus guidance favors them in SCN8A gain-of-function disease but relatively contraindicates them in loss-of-function disease. In SCN2A epilepsy, later-onset disease was associated with less benefit and occasional seizure worsening. The cenobamate evidence cited here is a 12-participant observational series, not a randomized comparison with relutrigine.
Place in treatment, anticipated use, and care setting
Summary
The studied use of relutrigine is as an investigational treatment for SCN2A- and SCN8A-related DEEs in participants already receiving antiseizure medications. In EMBOLD cohort 2, 34 participants exposed to relutrigine, representing 67%, were taking three to six ASMs at baseline. The manufacturer describes an oral or G/J-tube liquid formulation. Expanded-access requests require submission by the treating physician and are considered individually. These data describe study use and access arrangements, not an approved treatment position.
Heterogeneity of treatment effect
Treatment-response heterogeneity in SCN2A-associated epilepsy
Care management intervention strategies
Other product development or post-marketing obligations required by the FDA
Not applicable.
Ongoing post-approval monitoring
Not applicable.