The company’s lead investigational drug, radiprodil, is a selective negative allosteric modulator of the NMDA receptor subtype 2B (NR2B/GluN2B). It is being developed as a potential treatment for seizures associated with GRIN-related neurodevelopmental disorder (GRIN-NDD) with gain-of-function (GoF) mutations.

On February 25, 2025, GRIN Therapeutics announced that radiprodil received Breakthrough Therapy designation from the U.S. Food and Drug Administration (FDA). This designation is based on data from the Phase 1b Honeycomb study, which demonstrated a median 86% reduction in countable motor seizure (CMS) frequency in pediatric patients with GRIN-NDD. The company is preparing to initiate a Phase 3 pivotal trial in mid-2025 to further evaluate radiprodil’s efficacy and impact on both seizure and non-seizure symptoms.

GRIN Therapeutics operates as an affiliate of Neurvati Neurosciences, a portfolio company of Blackstone Life Sciences, which has committed $200 million in funding to support its research and development efforts. The company’s broader pipeline includes additional indications for radiprodil, including tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD) type II.