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Study on the Safety and Effects of Radiprodil for Children with GRIN-related Disorder

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying a condition known as GRIN-related disorder, which affects children. The trial will explore the effects of a treatment called Radiprodil, which is given as an oral suspension. Radiprodil is a chemical substance that is being tested to see how safe and tolerable it is for children with this disorder. The study aims to find out how the body processes Radiprodil and how it affects seizures and behavioral symptoms in children.

The study will involve children who have specific gene variants related to the NMDA receptor, which is a part of the brain that can be affected in GRIN-related disorder. The trial will be conducted in two parts. In the first part, children will receive different doses of Radiprodil to determine a safe and well-tolerated dose over eight weeks. The second part will continue to monitor the children who have already been treated to assess the long-term effects of the medication.

Throughout the study, researchers will keep track of any side effects, changes in vital signs, and other health indicators. They will also measure the levels of Radiprodil in the blood at specific times. The goal is to understand how Radiprodil can help manage seizures and improve behavioral symptoms in children with GRIN-related disorder, while ensuring the treatment is safe for long-term use.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial visit and consent

    Upon joining the study, the participant's caregiver will be asked to provide informed consent. If applicable, the participant will also provide assent. This is a formal agreement to participate in the study after understanding its purpose and procedures.

    The participant will undergo an initial assessment to confirm eligibility, which includes reviewing medical history and current treatments.

  2. Step 2

    Baseline assessment

    A comprehensive baseline assessment will be conducted. This includes physical examinations, vital signs measurement, and laboratory tests to establish the participant's health status before starting the treatment.

    The caregiver will be instructed on how to use the electronic diary (eDiary) to record daily seizure activity and any other relevant observations.

  3. Step 3

    Titration period

    The participant will begin taking radiprodil as an oral suspension. The dosage will be individually adjusted over a period of time to find the most effective and well-tolerated dose. This is known as the titration period.

    The caregiver will continue to record daily observations in the eDiary and report any side effects or changes in the participant's condition.

  4. Step 4

    Maintenance period

    Once the optimal dose is determined, the participant will continue taking radiprodil at this dose for a specified duration. This is the maintenance period.

    Regular follow-up visits will be scheduled to monitor the participant's response to the treatment and to conduct necessary tests, such as blood tests and electrocardiograms (ECG).

  5. Step 5

    End of treatment assessment

    At the end of the treatment period, a final assessment will be conducted. This includes a physical examination, laboratory tests, and a review of the eDiary entries to evaluate the treatment's impact on seizures and behavior.

    The caregiver will be asked to complete questionnaires to assess changes in the participant's quality of life and any caregiver burden experienced during the study.

  6. Step 6

    Follow-up

    After completing the study, there may be a follow-up period to monitor the participant's health and any long-term effects of the treatment.

    The caregiver will be contacted to provide additional information if necessary.

Who can join the trial?

9 criteria

  • Children aged between 6 months and 12 years with specific changes in the GRIN gene, which affects a part of the brain called the NMDA receptor.
  • For the first group of participants, the child must have at least one noticeable motor seizure per week and at least four noticeable motor seizures during a 4-week observation period. A motor seizure is a type of seizure that involves physical movements.
  • The child must have tried at least two different anti-seizure medications without success in controlling seizures.
  • For the second group of participants, the child must have significant behavior or movement issues as reported by their caregiver, with a specific score on a scale used to measure these symptoms.
  • Current treatments must be stable for at least 4 weeks before starting the study and should remain stable during the study. This includes any special diets like the ketogenic diet.
  • The child's caregivers must agree to participate by signing a consent form, and the child must also agree if they are able to understand.
  • The child's caregivers must be willing and able to fill out a daily electronic diary about the child's condition.
  • The child must be either not able to have children (due to age or gender) or, if able to have children, must not be pregnant, must not be breastfeeding, and must use an approved method of birth control.
  • For the second part of the study, the child must have completed at least 8 weeks of treatment in the first part and must still be benefiting from the treatment according to the doctor's assessment.

Who cannot join the trial?

10 criteria

  • Patients who do not have a GRIN-related disorder cannot participate.
  • Patients who are not within the specified age range for the study cannot participate.
  • Patients who are not able to follow the study procedures or take the study medication as required cannot participate.
  • Patients who have any other medical condition that might interfere with the study cannot participate.
  • Patients who are taking medications that might interfere with the study cannot participate.
  • Patients who have had a recent surgery or are planning to have surgery during the study cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate.
  • Patients who have a history of drug or alcohol abuse cannot participate.
  • Patients who have participated in another clinical trial recently cannot participate.
  • Patients who have any allergies to the study medication or its ingredients cannot participate.
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Investigated drugs

Radiprodil is a medication being studied to see how safe and tolerable it is for children with a condition called GRIN-related disorder. This disorder can cause seizures and behavioral problems. In this trial, radiprodil is given in addition to the usual treatments that the children are already receiving. The goal is to find out if radiprodil can be safely used over a long period and to determine the right amount that can be given without causing too many side effects. Researchers are also looking at how the body processes radiprodil and how much of it gets into the blood after taking it.

What is already known about the treatment

Radiprodil – Radiprodil is administered orally and is being studied for its safety and effectiveness in children with GRIN-related disorder, a condition that affects brain function. Currently, it is in clinical trials to assess its impact on seizures and behavioral symptoms. The medication works by modulating certain receptors in the brain to help stabilize neural activity. It is classified as a neurological agent, and researchers are focusing on finding a safe and well-tolerated dose for long-term use.

Investigated diseases

GRIN-related disorder – GRIN-related disorder is a genetic condition caused by mutations in the GRIN genes, which are responsible for encoding subunits of NMDA receptors in the brain. These receptors play a crucial role in synaptic transmission and plasticity, which are essential for learning and memory. The disorder can lead to a range of neurological symptoms, including developmental delays, intellectual disabilities, and movement disorders. As the condition progresses, individuals may experience seizures and behavioral challenges. The severity and specific symptoms can vary widely among affected individuals. The disorder is considered rare and can significantly impact the quality of life.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-509672-42-00Protocol codeRAD-GRIN-101Estimated enrolment120 patientsSponsorGrin Therapeutics Inc.

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