Diet Treatment Glucose Transporter Type 1 Deficiency (G1D)
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ClinicalTrials.gov Identifier: NCT03181399 |
Recruitment Status :
Active, not recruiting
First Posted : June 8, 2017
Last Update Posted : May 3, 2023
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Condition or disease | Intervention/treatment | Phase |
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GLUT1DS1 Epilepsy Glut1 Deficiency Syndrome 1, Autosomal Recessive Glucose Metabolism Disorders Glucose Transport Defect Glucose Transporter Type 1 Deficiency Syndrome Glucose Transporter Protein Type 1 Deficiency Syndrome | Drug: Triheptanoin | Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 45 participants |
Allocation: | N/A |
Intervention Model: | Single Group Assignment |
Intervention Model Description: | All subjects will receive supplementation at the maximum tolerated dose. |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | Dietary Treatment of Glucose Transporter Type 1 Deficiency (G1D) |
Actual Study Start Date : | April 18, 2018 |
Estimated Primary Completion Date : | September 30, 2023 |
Estimated Study Completion Date : | September 30, 2023 |

Arm | Intervention/treatment |
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Experimental: Triheptanoin
This is a single arm study.
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Drug: Triheptanoin
. Triheptanoin will be taken 4 times per day (approximately every 6 hours: prior to breakfast, lunch and dinner and a mid-afternoon snack) by mouth. It is dosed 4 times per day, divided evenly.
Other Name: C7 |
- Neuropsychological attention scores [ Time Frame: Medication taken daily for 6 months. ]To evaluate the impact of triheptanoin supplementation on measures of neuropsychological function primarily indicative of attention in G1D subjects receiving normal diet. These measures include one of two quantitative scales WPPSI-IV (Wechsler Preschool and Primary Scale of Intelligence; if younger than 7 years old), or WASI-II (Wechsler Abbreviated Scale of Intelligence; if older than 8 years old) depending on age.
- EEG changes: spike-wave activity duration in EEG (electroencephalogram) tracings [ Time Frame: Medication taken daily for 6 months. ]Expecting to find a greater than 30% decrease in spike-wave activity determined as percent duration of spike-wave activity over the total duration of EEG.
- Ataxia scores [ Time Frame: Medication taken daily for 6 months. ]
Ataxia is scored 0 (normal; no ataxia) to 30 (severe ataxia) per modified ICARS ( International Cooperative Ataxia Rating Scale) scale in Schmahmann, J. D., Gardner, R., MacMore, J. and Vangel, M. G. (2009), Development of a brief ataxia rating scale (BARS) based on a modified form of the ICARS.
Mov. Disord., 24: 1820-1828
- Global impression scale [ Time Frame: Medication taken daily for 6 months. ]Scores range from 1 (very much improved) through to 7 (very much worse)

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Ages Eligible for Study: | 24 Months to 35 Years (Child, Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Diagnosis of glucose transporter type I deficiency (G1D), confirmed by clinical genotyping at a CLIA-certified laboratory or by PET scan.
- Stable diet on either a modified atkins diet or on no dietary therapy (i.e., no dietary therapy for 1 month).
- Males and females 24 months to 35 years old, inclusive.
Exclusion Criteria:
- Subjects with evidence of independent, unrelated metabolic and/or genetic disease.
- Subjects with a chronic gastrointestinal disorder, such as irritable bowel syndrome, Crohn's disease, or colitis that could increase the subject's risk of developing diarrhea or stomach pain.
- Subjects with a BMI (body mass index) greater than or equal to 30.
- Subjects currently on dietary therapy (i.e., ketogenic diet, medium chain triglyceride supplemented diets, Atkins diet, low glycemic index diet).
- Subjects with no evidence of abnormal EEG (spike wave discharges) in the last 12 months.
- Women who are pregnant or breast-feeding may not participate. Women who plan to become pregnant during the course of the study, or who are unwilling to use birth control to prevent pregnancy (including abstinence) may not participate. Females age 10 and over will be asked to provide a urine sample for a pregnancy test via dipstick. Subjects will be asked to agree to abstinence or another form of birth control for the duration of the study.
- Allergy/sensitivity to C7.
- Previous use of triheptanoin in the past 1 month. Subjects who participate in Protocol 1 of this study are thus eligible.
- Subjects exhibiting signs of dementia, or diagnosed with any degenerative brain disorder (such as Alzheimer's disease) that would confound assessment of cognitive changes, in the opinion of the investigator.
- Active drug or alcohol use or dependence that, in the opinion of the investigator, would interfere with adherence to study requirements.
- Inability or unwillingness of subject or legal guardian/representative to give written informed consent, or assent for children age 10-17.
- Addition of a new antiseizure drug in the previous 3 months.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03181399
United States, Texas | |
University of Texas Southwestern Medical Center | |
Dallas, Texas, United States, 75390 |
Principal Investigator: | Juan Pascual, MD | Study Principal Investigator |
Responsible Party: | Juan Pascual, Professor of Medicine, University of Texas Southwestern Medical Center |
ClinicalTrials.gov Identifier: | NCT03181399 |
Other Study ID Numbers: |
122016-013 1R01NS094257-01A1 ( U.S. NIH Grant/Contract ) |
First Posted: | June 8, 2017 Key Record Dates |
Last Update Posted: | May 3, 2023 |
Last Verified: | April 2023 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Metabolic Diseases Glucose Metabolism Disorders Syndrome Disease Pathologic Processes |