A Clinical Trial of PRAX-222 in Pediatric Participants With Early Onset SCN2A Developmental and Epileptic Encephalopathy

NCT05737784 | Recruiting Phase 1 DMC FDA Drug

• 1 other identifier: PRAX-222-111
• Study Type: interventional
• Target: 60
• Locations: 2 countries
• Sites: 3

Brief Summary

The goal of this trial is to learn about the effect of PRAX-222 in pediatric participants with early onset SCN2A developmental and epileptic encephalopathy (DEE), aged 2 to 18 years.

Conditions

SCN2A-DEE; Epilepsy

Keywords

Antisense Oligonucleotide; NaV1.2 Voltage-Gated Sodium Channel; Voltage-Gated Sodium Channel Blockers; SCN2A variant; Pediatric epilepsy; Developmental and Epileptic Encephalopathy; DEE

Outcome Measures

Primary Outcomes (2)

• Number of participants with treatment-emergent adverse events (Preliminary Safety, Dose Escalation)

  The number of participants with treatment-emergent adverse events will be reported by severity and preferred term.

  Screening (-8 weeks) through up to 92 weeks

• Seizure frequency (Confirmatory Phase)

  Seizure frequency will be captured by a seizure diary and outcomes will be measured by summing the seizure frequency over a 28-day time period following the 6th dose administration in the confirmatory phase.

  36 to 40 weeks

Secondary Outcomes (21)

• Seizure frequency (Preliminary Safety)

  12 to 16 weeks

• Seizure frequency (Preliminary Safety)

  0 to 4 weeks, 4 to 8 weeks, 8 to 12 weeks

• Percent change in seizure frequency (Preliminary Safety)

  0 to 4 weeks, 4 to 8 weeks, 8 to 12 weeks

• Number of participants with a treatment response (Preliminary Safety)

  0 to 4 weeks, 4 to 8 weeks, 8 to 12 weeks

• Seizure frequency (Dose Escalation Phase)

  24 to 28 weeks (Group 1), 30 to 34 weeks (Group 2, optional)

Study Arms (8)

Preliminary Safety

EXPERIMENTAL

Open-label PRAX-222

Drug: PRAX-222 - Initial Dose

Dose Escalation - PRAX-222

EXPERIMENTAL

Initial dose escalation consisting of double-blind ascending doses of PRAX-222

Drug: PRAX-222 - Initial Ascending Doses

Dose Escalation - Placebo

PLACEBO COMPARATOR

Double-blind placebo procedure

Procedure: Placebo

Optional Dose Escalation - PRAX-222

EXPERIMENTAL

Optional dose escalation consisting of double-blind ascending doses of PRAX-222

Drug: PRAX-222 - Optional Ascending Doses

Optional Dose Escalation - Placebo

PLACEBO COMPARATOR

Double-blind placebo procedure

Procedure: Placebo

Confirmatory Dosing - PRAX-222

EXPERIMENTAL

Double-blind fixed-dose PRAX-222

Drug: PRAX-222 - Fixed Doses

Confirmatory Dosing - Placebo

EXPERIMENTAL

Double-blind placebo procedure

Procedure: Placebo

Open-label PRAX-222

EXPERIMENTAL

Open-label PRAX-222

Drug: PRAX-222 - Fixed Doses

Interventions

PRAX-222 - Initial Dose DRUG

PRAX-222

Preliminary Safety

PRAX-222 - Initial Ascending Doses DRUG

Ascending doses of PRAX-222

Dose Escalation - PRAX-222

PRAX-222 - Optional Ascending Doses DRUG

Escalation of PRAX-222 dose(s)

Optional Dose Escalation - PRAX-222

PRAX-222 - Fixed Doses DRUG

Fixed-dose(s) of PRAX-222 not to exceed the maximum tolerated dose of PRAX-222

Confirmatory Dosing - PRAX-222; Open-label PRAX-222

Placebo PROCEDURE

Placebo procedure

Confirmatory Dosing - Placebo; Dose Escalation - Placebo; Optional Dose Escalation - Placebo

Eligibility Criteria

• Age: 2 Years - 18 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Has onset of seizures prior to 3 months of age.
• Has a minimum weight of at least 10 kg at screening.
• Has a documented SCN2A variant through genetic testing obtained via a laboratory accredited per Clinical Laboratory Improvement Amendments (CLIA) or College of American Pathologists (CAP) or equivalent.

You may not qualify if:

• Has any clinically significant or known pathogenic genetic variant other than in the SCN2A gene, or a genetic variant that may explain or contribute to the participant's epilepsy and/or developmental disorder.
• Is taking more than 2 sodium channel blocking anti-seizure medications

Sponsors & Collaborators

• Praxis Precision Medicines: lead

Study Sites (3)

Le Bonheur Childrens Hospital

Memphis, Tennessee, 38103, United States

COMPLETED

Hospital de Clinicas de Porto Alegre

Porto Alegre, Rio Grande do Sul, 90035-003, Brazil

RECRUITING

Praxis Research Site

São Paulo, 05403-010, Brazil

RECRUITING

Related Links

• Related Info

MeSH Terms

Conditions

Epilepsy

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Study Officials

• Medical Director

  Praxis Precision Medicines

  STUDY DIRECTOR

Central Study Contacts

Head of Pharmacovigilance

CONTACT

617-300-8460; clinicaltrials@praxismedicines.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: No masking in the 2 open-label parts, masking as indicated in the 2 double-blind, randomized parts.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Seamless study design with sequential study parts, including an open-label safety part; a double-blind, randomized dose-escalation part; a double-blind, randomized confirmatory part; and an open-label extension part.

Study Record Dates

• First Submitted: February 10, 2023
• First Posted: February 21, 2023
• Study Start: April 13, 2023
• Primary Completion: August 1, 2025
• Study Completion (Estimated): September 1, 2027
• Last Updated: August 21, 2025

Record last verified: 2024-10

Data Sharing

• IPD Sharing: Will not share

Locations

BR (2); US (1)