A Multinational, Multicenter Study With an Open-Label Phase 1b and a Randomized, Double-Blind, Placebo-Controlled Phase 3 Followed by an Open-Label Extension to Assess the Efficacy, Safety, Tolerability, and Pharmacokinetics of Radiprodil in Participants With GRIN-Related Neurodevelopmental Disorder
GRIN Therapeutics, Inc.
Summary
The Phase 3 portion of Study RAD-GRIN-101 is a multinational, multicenter, randomized, double-blind, placebo-controlled trial followed by an open-label extension to evaluate the efficacy and safety of radiprodil in participants with GRIN-related neurodevelopmental disorder (GRIN-NDD) with a gain-of-function (GoF) genetic variant. This study will enroll two cohorts: one cohort of participants with a minimal number of countable motor seizures (with or without behavioral symptoms) (Phase 3 Cohort 1: Qualifying Seizures Cohort); and a second cohort with disease symptoms but no seizures or fewer seizures than required for the Qualifying Seizures Cohort (Phase 3 Cohort 2: Without Qualifying Seizures Auxiliary Cohort). Participants in each cohort will be randomized 1:1 to receive active drug (radiprodil) or matching placebo (Part A). Following completion of Part A, all eligible participants (including those previously on placebo) may continue into the open-label extension period (Part B) to receive radiprodil. The placebo-controlled portion is expected to be approximately 16 weeks for participants in Phase 3 Cohort 1 and 28 weeks for participants in Phase 3 Cohort 2. The study will evaluate the effect of radiprodil on seizures and non-seizure symptoms and assess safety.
Description
Participants are assigned in a 1:1 ratio to receive either radiprodil or placebo during Part A with the opportunity to receive radiprodil in the Open-Label Extension, Part B. The dosing regimen includes a fixed titration schedule over 4 weeks. This study is divided into the following parts: Part A: Randomized, double-blind, placebo-controlled * Screening/Observation Period: To assess eligibility * Titration Period (approximately 4 weeks): Titration of radiprodil or placebo to target dose * Maintenance Period (Part A): Target dose of radiprodil or placebo maintained for 12 weeks (Phase 3 Coh…
Eligibility
- Age range
- 0–18 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: Part A, Participant: * Diagnosed with GRIN-NDD with GRIN1, GRIN2A, GRIN2B, or GRIN2D gene variants known to result in GoF of the NMDA receptor * Phase 3 Cohort 1 (Qualifying Seizures Cohort) ONLY: Experiencing at least 1 CMS per week and ≥4 CMS (generalized or focal) during screening * With history of inadequate response to at least 2 standard antiseizure medications (ASMs) * Phase 3 Cohort 2 (Without Qualifying Seizures Auxiliary Cohort) ONLY: With significant neurodevelopmental symptoms and a GRIN-CGI-S score ≥4 * On a stable dose of standard ASMs for at least 4 weeks p…
Interventions
- DrugRadiprodil
Radiprodil oral suspension
- DrugPlacebo
Placebo-to-match radiprodil oral suspension
Locations (17)
- UCLA Clinical & Translational Research CenterLos Angeles, California
- Lucile Packard Children's HospitalPalo Alto, California
- Children's Hospital Colorado - Anschutz Medical CampusAurora, Colorado
- Children's National HospitalWashington D.C., District of Columbia
- Nicklaus Children's HospitalMiami, Florida
- Pediatric Neurology and EpilepsyWinter Park, Florida