A Phase 1/2 interventional study of Radiprodil in Tuberous Sclerosis Complex and Focal Cortical Dysplasia, sponsored by GRIN Therapeutics, Inc.. Active, not recruiting at 18 sites in 8 countries. Open to participants aged 6 Months to 18 Years. Per ClinicalTrials.gov, last updated 2026-04-01.
Sponsored by GRIN Therapeutics, Inc. · Phase 1/2, Interventional, and Treatment
Study RAD-GRIN-201 is a phase 1B/2A trial to assess safety, tolerability, pharmacokinetics (PK), and potential efficacy of radiprodil in participants with Tuberous Sclerosis Complex (TSC) or Focal Cortical Dysplasia (FCD) type II. The study is open-label, so all participants will be treated with radiprodil. Subjects' participation in the study is expected to last up to six months in Part A and one year in Part B/long-term treatment period. The treatment period in Part B may be extended based on a favorable benefit/risk profile.
Approximately 20 participants with TSC and 10 participants with FCD type II will be enrolled.
The effects of radiprodil are assessed in participants with treatment-resistant seizures (with or without behavioral symptoms). The daily doses of radiprodil will be individually titrated for every participant and all the participants will receive study drug.
This study is divided into the following periods:
PART A:
PART B:
115 studies on the registry are indexed under Tuberous Sclerosis; 27 are open to participants now.
This study's planned enrollment of 30 is below the median of 52 across 73 interventional studies indexed under Tuberous Sclerosis.
Browse Tuberous Sclerosis studies →GRIN Therapeutics, Inc. is the lead sponsor of 7 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Disease specific criteria:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Child-Pugh class
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Liquid suspension of radiprodil, at concentrations 0.25 mg/mL, 2.50 mg/mL or 7.5 mg/mL for 1%, 10% and 30% formulation respectively. It will be administered twice a day (bid) either orally or via gastric or nasogastric tube.
Drug: Radiprodil
Liquid suspension of radiprodil, at concentrations 0.25 mg/mL, 2.50 mg/mL or 7.5 mg/mL for 1%, 10% and 30% formulation respectively. It will be administered twice a day (bid) either orally or via gastric or nasogastric tube.
Drug: Radiprodil
Radiprodil is an orally active, negative allosteric modulator of the NR2B subunit of the NMDA receptor.
Incidence of Treatment-Emergent Adverse Events (TEAEs), Serious TEAEs (SAEs), Adverse Drug Reactions (ADRs), TEAEs Leading to Discontinuation and Severity of TEAEs
Frequency, type, severity and duration of adverse events, serious adverse events and adverse drug reactions.
Time frame: from Baseline to End-of-study: 1 year 6 months
Plasma concentration of radiprodil and maximum plasma concentration (Cmax)
Time frame: Titration Visit 1 (week 7): Pre-dose to 12 hours post-dose. Titration Visits 2,3,4 (week 8 to 13) and Maintenance Visit 7 (week 25): pre-dose to 5 hours post-dose
Plasma concentration of radiprodil versus time, area under the curve (AUCt)
Time frame: Titration Visit 1 (week 7): Pre-dose to 12 hours post-dose. Titration Visits 2,3,4 (week 8 to 13) and Maintenance Visit 7 (week 25): pre-dose to 5 hours post-dose
Pharmacokinetic plasma concentration of radiprodil: half-life (T1/2)
Time frame: Titration Visit 1 (week 7): Pre-dose to 12 hours post-dose. Titration Visits 2,3,4 (week 8 to 13) and Maintenance Visit 7 (week 25): pre-dose to 5 hours post-dose
Pharmacokinetic plasma concentration of radiprodil: time to Cmax (Tmax)
Time frame: Titration Visit 1 (week 7): Pre-dose to 12 hours post-dose. Titration Visits 2,3,4 (week 8 to 13) and Maintenance Visit 7 (week 25): pre-dose to 5 hours post-dose
Pharmacokinetic plasma concentration of radiprodil, clearance (Cl)
Time frame: Titration Visit 1 (week 7): Pre-dose to 12 hours post-dose. Titration Visits 2,3,4 (week 8 to 13) and Maintenance Visit 7 (week 25): pre-dose to 5 hours post-dose
Number of participants with abnormal laboratory tests results
The clinical laboratory tests include Hematology, Serum Chemistry and Coagulation
Time frame: from Baseline to End-of-study: 1 year 6 months
Number of participants with abnormal physical and neurological examination findings
A complete physical and neurological examination according to standard of care excluding the genitourinary examination will be performed
Time frame: Baseline, MV7, and in Part B: Month 3, 6, 9, 12: week 6, week 28, week 40, week 52, week 64, week 76
Clinically relevant changes in safety parameters: systolic blood pressure
changes from Baseline to End of study for systolic blood pressure
Time frame: from Baseline to End-of-study: 1 year 6 months
Clinically relevant changes in safety parameters: diastolic blood pressure
changes from Baseline to End of study for diastolic blood pressure
Time frame: from Baseline to End-of-study: 1 year 6 months
Clinically relevant changes in safety parameters: pulse rate
changes from Baseline to End of Treatment for pulse rate
Time frame: from Baseline to End-of-study: 1 year 6 months
12-Lead ECG: Mean change from Baseline to End-of-Treatment in RR interval
Time frame: from Baseline to End-of-study: 1 year 6 months
12-Lead ECG: Mean change from Baseline to End-of-Treatment in PR interval
Time frame: from Baseline to End-of-study: 1 year 6 months
12-Lead ECG: Mean change from Baseline to End-of-Treatment in QRS interval
Time frame: from Baseline to End-of-study: 1 year 6 months
12-Lead ECG: Mean change from Baseline to End-of-Treatment in QT interval
Time frame: from Baseline to End-of-study: 1 year 6 months
12-Lead ECG: Mean change from Baseline to End-of-Treatment in QTcF interval
Time frame: from Baseline to End-of-study: 1 year 6 months
Percent change from baseline in Video-EEG seizure burden
Assessed by 8- to 24- hour video electroencephalogram
Time frame: Baseline to end-of-treatment: week 6 to week 76
Change from baseline in seizure frequency
assessed by seizure diaries
Time frame: Baseline to Maintenance Visit 7: week 6 to week 25 and Baseline to end-of-treatment: week 6 to week 76
Change from baseline in number of seizure-free days and longest period with no seizures
assessed by seizure diaries
Time frame: Baseline to end-of-treatment: week 6 to week 76
Aberrant Behavior Checklist-Community (ABC-2C)
The ABC-2C is a standardized 58-item caregiver-reported problem-behavior rating scale, originally designed to assess treatment effects in people with intellectual disabilities. Each item is scored from 0 (never a problem) to 3 (severe problem). Items load onto one of five empirically derived subscales: Irritability, Agitation, \& Crying (15 items); Lethargy/Social Withdrawal (16 items); Stereotypic Behavior (7 items); Hyperactivity/Noncompliance (16 items); and Inappropriate Speech (4 items). A total score would range from 0 to 174.
Time frame: Baseline to end-of-treatment: week 6 to week 76
Caregiver Global Impression of Change (CaGI-C)
The CaGI-C is a 7-point caregiver-rated scale ranging from 1 (very much improved) to 7 (very much worse).
Time frame: Baseline to end-of-treatment: week 6 to week 76
Clinical Global Impression of Change [CGI-C]
The CGI scale is a clinician-rated measures of change of a symptom or condition, using a single item, 6- or 7-point scale. The CGI-C scale ranges from 1 ("Very much worse") to 7 ("Very much improved").
Time frame: Baseline to end-of-treatment: week 6 to week 76
Pediatric Quality of Life Inventory [PedsQL]
The PedsQL is a 23-item generic health status instrument assessing 5 domains of health in children. It's a 0-100 scale, and higher scores are indicative of better health-related quality of life.
Time frame: Baseline to end-of-treatment: week 6 to week 76
Caregiver Burden Inventory (CBI)
The CBI is a validated scale providing information regarding the impact of caregiving on the lives of caregivers. It comprises 24 closed questions divided into 5 dimensions. Each dimension includes 4 or 5 items. Each item is given a score between 0 and 4, where higher scores indicate greater caregiver burden.
Time frame: Baseline to end-of-treatment: week 6 to week 76
Columbia-Suicide Severity Rating Scale (C-SSRS)
The C-SSRS is a validated tool designed to systematically evaluate the severity and intensity of suicidal ideation and behavior. The scoring system ranges from 0 to 5 for suicidal ideation and from 0 to 25 for suicidal behavior, with higher scores indicating greater severity or greater frequency of suicidal thoughts or actions.
Time frame: Baseline to end-of-treatment: week 6 to week 76
This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Radiprodil
GRIN Therapeutics, Inc.