Diet Treatment Glucose Transporter Type 1 Deficiency (G1D)
Dietary Treatment of Glucose Transporter Type 1 Deficiency (G1D)
2 other identifiers
interventional
45
1 country
1
Brief Summary
Forty-five subjects receiving no dietary therapy with a proven G1D diagnosis will be enrolled. To evaluate the effect of C7 supplementation of a regular diet on a EEG activity in addition to IQ, language, working memory, processing speed, emotional and behavioral functioning, ataxia, and other neuropsychological and neurological performance indices in children and adults genetically diagnosed with G1D receiving a regular diet at enrollment.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for phase_2
Started Apr 2018
Longer than P75 for phase_2
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
April 25, 2017
CompletedFirst Posted
Study publicly available on registry
June 8, 2017
CompletedStudy Start
First participant enrolled
April 18, 2018
CompletedPrimary Completion
Last participant's last visit for primary outcome
September 10, 2023
CompletedStudy Completion
Last participant's last visit for all outcomes
September 10, 2023
CompletedResults Posted
Study results publicly available
April 13, 2025
CompletedAugust 7, 2025
July 1, 2025
5.4 years
April 25, 2017
March 26, 2025
July 28, 2025
Conditions
Outcome Measures
Primary Outcomes (6)
Neuropsychological Score of Sustained Attention
Sustained attention was evaluated using a subtest of Conners' Kiddie Continuous Performance Test Second Edition (K-CPT 2): CPT-Hit Reaction Time Block Change. CPT HRT BC indicates the change in mean response speed as the administration of the test progresses in blocks. A decrease in CPT HRT BC indicates a decrease in reaction time, which means the participant's information processing efficiency increases, and an improvement in sustained attention is noted. The number of participants that showed a decrease in the CPT HRT BC score after 6 months of treatment as compared to baseline is noted here.
Change post 6 months of treatment
Neuropsychological Score of Sustained Attention
Sustained attention was evaluated using a subtest of Conners' Kiddie Continuous Performance Test Second Edition (K-CPT 2): CPT-Hit Reaction Time Block Change. CPT HRT BC indicates the change in mean response speed as the administration of the test progresses in blocks. A decrease in CPT HRT BC indicates a decrease in reaction time, which means the participant's information processing efficiency increases, and an improvement in sustained attention is noted. The off-treatment period of 3 months was implemented to study whether the impact of treatment persists or goes back to baseline. The number of patients that displayed an increase in CPT HRT BC score (towards baseline) after 3 months off treatment as compared to 6 months on treatment is noted here.
Change after 3 months off treatment
Neuropsychological Score of Working Memory Index Scale (WMI)
Subjects were administered the Working Memory Index Scale (WMI) from either the Wechsler Primary and Preschool Scale of Intelligence, 4th Edition (WPPSI-IV), Wechsler Intelligence Scale for Children, 5th Edition (WISC-V), or the Wechsler Adult Intelligence Scale, 4th Edition (WAIS-IV) according to the age of subject. An increase WMI score would indicate an improvement in the cognitive ability of identifying, reorganizing and retaining information for a brief period of time. The number of participants that showed an increase in the WMI score after 6 months of treatment is noted here.
Change post 6 months of treatment
Neuropsychological Score of Working Memory Index Scale (WMI)
Subjects were administered the Working Memory Index Scale (WMI) from either the Wechsler Primary and Preschool Scale of Intelligence, 4th Edition (WPPSI-IV), Wechsler Intelligence Scale for Children, 5th Edition (WISC-V), or the Wechsler Adult Intelligence Scale, 4th Edition (WAIS-IV) according to the age of subject. An increase WMI score would indicate an improvement in the cognitive ability of identifying, reorganizing and retaining information for a brief period of time. The 3 months off-treatment period was designed to study whether the impact of treatment persists or goes back to baseline. The number of participants that showed a decrease in the WMI score after 3 months off treatment as compared to 6 months on treatment was calculated.
Change after 3 months off-treatment
Neuropsychological Score of Processing Speed Index (PSI)
Subjects were administered the Processing Speed Index Scale (PSI) from either the Wechsler Primary and Preschool Scale of Intelligence, 4th Edition (WPPSI-IV), Wechsler Intelligence Scale for Children, 5th Edition (WISC-V) or the Wechsler Adult Intelligence Scale, 4th Edition (WAIS-IV) according to the age of subject. An increase PSI score would indicate an improvement in the motor-based estimate of the subject's cognitive processing speed. The number of participants that showed an increase in the PSI score after 6 months of treatment as compared to baseline is noted here.
Change post 6 months of treatment
Neuropsychological Score of Processing Speed Index (PSI)
Subjects were administered the Processing Speed Index Scale (PSI) from either the Wechsler Primary and Preschool Scale of Intelligence, 4th Edition (WPPSI-IV), Wechsler Intelligence Scale for Children, 5th Edition (WISC-V) or the Wechsler Adult Intelligence Scale, 4th Edition (WAIS-IV) according to the age of subject. An increase PSI score would indicate an improvement in the motor-based estimate of the subject's cognitive processing speed. The 3 months off-treatment period was designed to study whether the impact of treatment persists or goes back to baseline. The number of participants that showed a decrease in the WMI score after 3 months off treatment as compared to 6 months on treatment was calculated.
Change after 3 months off-treatment
Secondary Outcomes (6)
EEG Changes: Generalized Spike Wave Activity and Burst
Change post 6 months of treatment
EEG Changes: Generalized Spike Wave Activity and Burst
Change after 3 months off-treatment
Brief Ataxia Rating Scale
Change post 6 months of treatment
Brief Ataxia Rating Scale
Change after 3 months off treatment
Clinical Global Impression Severity Scale
Change post 6 months of treatment
- +1 more secondary outcomes
Study Arms (1)
Triheptanoin
EXPERIMENTALThis is a single arm study.
Interventions
. 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.
Eligibility Criteria
You may qualify if:
- 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.
You may not qualify if:
- 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.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
University of Texas Southwestern Medical Center
Dallas, Texas, 75390, United States
Related Publications (3)
Pascual JM, Ronen GM. Glucose Transporter Type I Deficiency (G1D) at 25 (1990-2015): Presumptions, Facts, and the Lives of Persons With This Rare Disease. Pediatr Neurol. 2015 Nov;53(5):379-93. doi: 10.1016/j.pediatrneurol.2015.08.001. Epub 2015 Aug 10.
PMID: 26341673BACKGROUNDHao J, Kelly DI, Su J, Pascual JM. Clinical Aspects of Glucose Transporter Type 1 Deficiency: Information From a Global Registry. JAMA Neurol. 2017 Jun 1;74(6):727-732. doi: 10.1001/jamaneurol.2017.0298.
PMID: 28437535BACKGROUNDPascual JM, Liu P, Mao D, Kelly DI, Hernandez A, Sheng M, Good LB, Ma Q, Marin-Valencia I, Zhang X, Park JY, Hynan LS, Stavinoha P, Roe CR, Lu H. Triheptanoin for glucose transporter type I deficiency (G1D): modulation of human ictogenesis, cerebral metabolic rate, and cognitive indices by a food supplement. JAMA Neurol. 2014 Oct;71(10):1255-65. doi: 10.1001/jamaneurol.2014.1584.
PMID: 25110966BACKGROUND
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Results Point of Contact
- Title
- Dr. Juan Pascual
- Organization
- Weill Cornell Medicine
Study Officials
- PRINCIPAL INVESTIGATOR
Juan Pascual, MD
Study Principal Investigator
Publication Agreements
- PI is Sponsor Employee
- No
- Restrictive Agreement
- No
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- NA
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- SINGLE GROUP
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Professor of Medicine
Study Record Dates
First Submitted
April 25, 2017
First Posted
June 8, 2017
Study Start
April 18, 2018
Primary Completion
September 10, 2023
Study Completion
September 10, 2023
Last Updated
August 7, 2025
Results First Posted
April 13, 2025
Record last verified: 2025-07
Data Sharing
- IPD Sharing
- Will not share