EU Orphan Status Recommended for GRIN Therapeutics' Radiprodil in Treating GRIN Neurodevelopmental Disorder

GRIN Therapeutics, Inc., a prominent figure in the field of neurodevelopmental disorder therapies, recently received a positive nod from the European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) for its investigational drug radiprodil. This drug is designed to address GRIN-related neurodevelopmental disorder (GRIN-NDD), a severe developmental and epileptic encephalopathy caused by specific receptor variants.

Radiprodil functions as a selective and potent negative allosteric modulator of the GluN2B subunit of the NMDA receptor. The condition it targets, GRIN-NDD, arises from mutations in GRIN genes, which encode essential subunits of the NMDA receptor crucial for maintaining neural circuitry balance. Symptoms can manifest early in life, typically requiring confirmation through further evaluation when developmental milestones are not met. Those affected may experience developmental delays, intellectual disabilities, seizures, and various other physical and behavioral challenges. Currently, no therapies specifically approved for GRIN-NDD exist.

The drug has also gained recognition from the U.S. Food and Drug Administration, securing both Orphan Drug and Breakthrough Therapy designations. These recognitions, along with the EMA's recent decision, underscore the potential of radiprodil to become a pioneering treatment for those afflicted by this disorder. GRIN Therapeutics plans to initiate a global Phase 3 clinical trial for radiprodil by mid-2025, further advancing its development.

Anne-Marie Li-Kwai-Cheung, Senior Vice President at Neurvati Neurosciences and GRIN Therapeutics, remarked on the milestone, emphasizing the urgent need for disease-modifying therapies that can tackle the comprehensive symptoms of GRIN-NDD. She highlighted the support from both the EMA and FDA, pointing to their understanding of the disorder's impact and the necessity for rapid progress in the development of radiprodil.

The EMA's orphan designation is reserved for drugs treating life-threatening or chronically debilitating diseases with a low prevalence across the European Union. Such designation brings several benefits, including market exclusivity and fee reductions, once the drug enters the market.

In earlier trials, radiprodil demonstrated promising results. Data from the Phase 1b/2a Honeycomb trial indicated a significant reduction in motor seizure frequency among pediatric patients with GRIN-NDD possessing gain-of-function mutations. Most patients experienced more than a 50% reduction in seizures, and overall clinical improvements were noted by both clinicians and caregivers. The drug also showed a favorable safety profile, with adverse events commonly linked to infections or pre-existing symptoms.

Beyond GRIN-NDD, radiprodil is being explored for other conditions such as tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD). Research suggests that radiprodil's modulation of the GluN2B receptor could potentially address symptoms related to these disorders, including seizures and behavioral issues. The ongoing RAD-GRIN-201 trial, also known as the Astroscape trial, is evaluating the drug's safety and potential efficacy in individuals with TSC or FCD type II.

GRIN Therapeutics remains devoted to advancing precision therapeutics for pediatric neurodevelopmental disorders, driven by the aim of providing hope to affected patients and their families. An affiliate of Neurvati Neurosciences, GRIN Therapeutics continues to explore and develop innovative treatment options in collaboration with its partners.