GRIN Therapeutics
Advancing a targeted approach to the treatment of GRIN-related disorders and other types of pediatric epilepsy
Neurodevelopmental disorders represent significant areas of unmet need in healthcare. People affected by these disorders, predominantly children and young adults, can face a range of severe and devastating symptoms. In many cases, there are only limited or no treatments available.  GRIN Therapeutics is dedicated to the research and development of precision therapeutics for pediatric neurodevelopmental disorders with the goal of bringing hope to patients and caregivers.
GRIN Therapeutics is advancing promising research and development to assess the safety and efficacy of the investigational therapy radiprodil for the treatment of serious neurodevelopmental disorders including GRIN-related disorders, tuberous sclerosis complex (TSC), and focal cortical dysplasia (FCD).
In many cases, pediatric neurodevelopmental disorders are rare diseases that are not widely known or understood.  In our effort to potentially bring new options to people living with pediatric neurodevelopmental disorders, GRIN Therapeutics is privileged to work with many of the global leaders in research, patient care, and advocacy to help build broader awareness of the impact of these disorders among patients, caregivers and communities.

The Role of N-methyl-D-aspartate (NMDA) Receptors in Neurodevelopmental Disorders

Neurodevelopmental disorders involve a malfunction of the brain and nervous system. They are generally associated with devastating symptoms that can include seizures and epilepsy, delayed development, difficulties with language and speech, impaired motor skills and behavioral problems, among other symptoms. In many cases, a diagnosis is not confirmed until symptoms become obvious or severe. Treatments, when available, typically involve a combination of physical and behavioral therapies, drugs, and home/school-based support.

In some cases, neurodevelopmental disorders are associated with a dysfunctional receptor known as NMDA. In the brain, NMDA receptors help regulate different physiological functions, including learning and memory. When these receptors are dysfunctional, neurodevelopmental syndromes can emerge with symptoms that include seizures, intellectual disabilities, and neurobehavioral symptoms. The ability to precisely control the activity of NMDA receptors could play a role in the treatment of a range of neurodevelopmental disorders. Radiprodil, an investigational oral selective modulator of the NR2B sub-unit of the NMDA receptor, is currently being developed by GRIN Therapeutics for the potential treatment of GRIN-related disorders as well as TSC and FCD.

About GRIN-related Disorders

GRIN-related disorders were first classified in 2010 and are a family of rare, genetically defined pediatric neurodevelopmental disorders caused by mutations in a group of genes known as “GRIN” genes that includes GRIN1, GRIN2A, GRIN2B, and GRIN2D. While symptoms of GRIN-related disorders can present as early as infancy, a diagnosis is often not confirmed until age two or later when a child fails to reach developmental milestones. A diagnosis can be established through genetic testing. Most people living with GRIN-related disorders develop disabilities that require continuous supervision. Currently, there are no FDA approved therapies for GRIN-related disorders.
There are several known classes of GRIN-related disorders, including:

GRIN1-related Disorders

Individuals affected by GRIN1-related disorders experience mild-to-severe developmental delays and intellectual disabilities. Other common manifestations include epilepsy, muscular hypotonia, movement disorders, spasticity, feeding difficulties, and behavioral problems.

GRIN2A-related Disorders

Individuals affected by GRIN2A-related disorders may experience developmental delays or intellectual disabilities. Many also develop speech disorders, epilepsy, muscular hypotonia, movement disorders, spasticity, feeding difficulties, and behavioral problems.

GRIN2B-related Disorders

Individuals affected by GRIN2B-related disorders experience developmental delays and intellectual disabilities. Other common manifestations include epilepsy, muscular hypotonia, movement disorders, spasticity, feeding difficulties, and behavioral problems.

GRIN2D-related Disorders

Individuals affected by GRIN2D-related disorders experience moderate-to-severe developmental delays and intellectual disabilities. Other common manifestations include epilepsy, muscular hypotonia, movement disorders, spasticity, feeding difficulties, and behavioral problems.
Additional information about GRIN-related disorders is available from international organizations including:

Living with GRIN-related Disorders

The Mighty - Seeking Refuge During a War While Raising a Child with GRIN2B Disorder

Patient Worthy- Rare Community Profiles: The Importance of Community While Raising a Child with GRIN2B Disorder

Progress in Research

GRIN Therapeutics is advancing the development of radiprodil, an investigational drug that has been shown in preclinical studies to target a receptor on the NMDA subunit called “NR2B.” Research has shown that abnormal activity of the NMDA receptor leads to the clinical manifestations of GRIN-related disorders.

About the Honeycomb Study

GRIN Therapeutics is conducting the Honeycomb Study, a Phase 1b open-label clinical trial to evaluate the safety, tolerability and pharmacokinetics of radiprodil as an add-on therapy to standard of care and its impact on symptoms including seizures, behavioral changes, sleep disruption and changes in motor function in children with GRIN-related disorders caused by gain-of-function (GoF) variants. This trial will include up to 24 participants between the ages of six months and 12 years who have been confirmed to have GoF variants causing GRIN-related disorders, including variants on the GRIN1, GRIN2A, GRIN2B, and GRIN2D genes. Upon completion of the treatment, participants may have the option to participate in a long-term extension study.
For additional information about the Honeycomb Study, visit or
Targeting Additional Disorders Associated with Abnormal Expression of NR2B

Based on its mechanism of action as observed in preclinical studies, radiprodil could also play a role in the treatment of disorders associated with abnormal expression of NR2B including TSC and FCD.  GRIN Therapeutics is planning to launch a proof-of-concept study to assess the potential benefits of radiprodil in the treatment of TSC and FCD.  The trial will begin enrolling patients in early 2024.

Additional information about TSC is available from organizations including:
Additional information about FCD is available from:

About the Astroscape Study

GRIN Therapeutics is planning to launch the Astroscape study, an open-label proof of concept study to assess the safety and tolerability of different doses of radiprodil in people living with TSC or FCD Type II.  The study will evaluate the effect of radiprodil on the frequency and severity of epileptic seizures and on other symptoms related to behavior, motor skills, sleep and quality of life. Approximately 30 patients will be treated with radiprodil. Participants may have the option to participate in a long-term extension phase of the study.
Astroscape - box logo - PNG

Our Commitment to Patients
and Families

At GRIN Therapeutics, we are privileged to work closely with leaders from different advocacy and treatment communities to continually ensure that our efforts reflect the unique needs of the individuals and families we serve.

To contact GRIN Therapeutics patient advocacy, click here.

Our Team

The GRIN Therapeutics team includes recognized leaders in neurodegenerative and central nervous system disorders, clinical research and drug development, and patient advocacy who are dedicated to making a positive difference for patients and families.

Bruce Leuchter, M.D.
President & CEO

Michael A. Panzara, M.D., MPH
Chief Medical Officer

Hillary Savoie, PhD
Director of Community Engagement and Communication

Elliott Ruiz
Vice President, Finance

GRIN Therapeutics News

GRIN Therapeutics Announces First Patient Dosed in Phase 1B Clinical Trial with Radiprodil for Treatment of GRIN-related Disorders

March 23, 2023 – Milestone represents initiation of first-ever clinical trial using NR2B-negative allosteric modulator to treat GRIN-related disorders.

GRIN Therapeutics is a subsidiary of Neurvati Neurosciences, a division of Blackstone Life Sciences.