Extension Study to Evaluate the Safety and Tolerability of NBI-921352 When Used With Anti-seizure Medications in Adults With Focal Onset Seizures

Sponsor

Neurocrine Biosciences (Industry)

Overall Status

Not yet recruiting

CT.gov ID

NCT05493293

Collaborator

(none)

100

Enrollment

Arm

Anticipated Duration (Months)

Study Details

Study Description

Brief Summary

This Phase 2, prospective, interventional, active extension study was designed to evaluate the long-term safety, tolerability, pharmacokinetics, and efficacy of NBI-921352 as adjunctive therapy in adult subjects with focal onset seizures who completed 11 weeks of treatment in randomized, double-blind, placebo-controlled Study NBI-921352-FOS2021. Eligible subjects may enroll directly following the completion of the Week 11 study visit of Study NBI-921352-FOS2021 or after a gap following completion of that study.

Condition or Disease	Intervention/Treatment	Phase
Focal Onset Seizure Focal Onset Epilepsy	Drug: NBI-921352	Phase 2

Study Design

Study Type:

Interventional

Anticipated Enrollment :

100 participants

Allocation:

N/A

Intervention Model:

Single Group Assignment

Masking:

None (Open Label)

Masking Description:

For subjects who enroll directly from Study NBI-921352-FOS2021, the study will include a Blinded Dose Conversion Period (1 week) before proceeding to the Open-Label Treatment Period.

Primary Purpose:

Treatment

Official Title:

Prospective, Long-Term, Interventional, Active Extension Study to Evaluate the Safety and Tolerability of NBI-921352 as Adjunctive Therapy in Subjects With Focal Onset Seizures (FOS)

Anticipated Study Start Date :

Sep 1, 2022

Anticipated Primary Completion Date :

Dec 1, 2025

Anticipated Study Completion Date :

Dec 1, 2025

Arms and Interventions

Arm	Intervention/Treatment
Experimental: NBI-921352 Treatment Treatment for up to 107 weeks.	Drug: NBI-921352 Tablets for oral administration

Arm

Intervention/Treatment

Experimental: NBI-921352 Treatment

Treatment for up to 107 weeks.

Drug: NBI-921352

Tablets for oral administration

Outcome Measures

Primary Outcome Measures

The subject incidence of serious treatment-emergent adverse events (TEAEs), TEAEs leading to study treatment discontinuation, and fatal TEAEs [Through Week 111]

Secondary Outcome Measures

Percentage change from baseline in 28-day focal onset seizure frequency during the treatment period [Baseline and Week 105 or Early Termination]
Treatment response defined as ≥50% reduction in 28-day focal onset seizure frequency during the treatment period compared with baseline [Baseline and Week 105 or Early Termination]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 67 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Key Inclusion Criteria:

Provided informed consent.
Completed 11 weeks of treatment in Study NBI-921352-FOS2021.
Stable treatment with at least 1 but not more than 4 antiseizure medicines.

Key Exclusion Criteria:

Have developed any other disorder for which the treatment takes priority over the treatment of focal onset seizure or is likely to interfere with study treatment or impair treatment compliance.