Bruce Leuchter, MD, Cofounder and CEO of Neurvati Neurosciences and GRIN Therapeutics, discusses topline results from clinical trial testing investigational radiprodil for GRINrelated disorders.

GRINrelated neurodevelopmental disorders are a family of rare genetic conditions caused by pathogenic mutations in the GRIN genes. These disorders are characterized by childhoodonset epilepsy, developmental delay, movement disorders, and features of autism spectrum disorder. The symptoms a child experiences and the severity of the disorder can vary widely. GRIN is not the name of a medical condition but rather is the name of the gene that is affected.

Radiprodil is an selective, potent negative allosteric modulator of the NmethylDaspartate (NMDA) receptor subtype 2B (NR2B or GluN2B). The investigational drug has been shown to modulate GluN2BNMDA and have an antiseizure effect.

As noted by Dr. Leuchter, the Honeycomb study was a phase 1b openlabel trial evaluating the safety, efficacy, and tolerability of radiprodil in the treatment of GRINrelated disorders. Fifteen pediatric patients with confirmed mutations in the GRIN1, GRIN2a, or GRIN2B genes were enrolled in the study. Primary objectives included assessing the safety and pharmacokinetics of the treatment. Secondary objectives focused on evaluating the efficacy of seizure and nonseizure outcomes.

In the study, radiprodil was observed to be generally well tolerated with common adverse events of infection or underlying diseaseassociated symptoms (pyrexia, diarrhea, respiratory tract infection, abnormal behavior, agitation, cough, dystonia, fatigue, and gastroenteritis). In patients treated with radiprodil, a median reduction of 86% in seizure frequency compared to baseline was observed. 71% of patients also had a greater than 50% reduction in countable motor seizures, 43% with greater than 90% reduction, and one patient completely seizure free.

A phase 3 clinical trial is expected to follow.

Chapters:
GRIN Therapeutics 00:00
GRINRelated Disorders 3:00
Diagnosis 6:00
Honeycomb Clinical Trial 9:05
Next Steps 15:33