Trial Outcomes & Findings for Diet Treatment Glucose Transporter Type 1 Deficiency (G1D) (NCT NCT03181399)

NCT ID: NCT03181399

Last Updated: 2025-08-07

Results Overview

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.

• Recruitment status: COMPLETED
• Study phase: PHASE2
• Target enrollment: 45 participants
• Primary outcome timeframe: Change post 6 months of treatment
• Results posted on: 2025-08-07

Participant Flow

Participant milestones

Measure	Triheptanoin This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
6 Months on Treatment STARTED	45
6 Months on Treatment COMPLETED	29
6 Months on Treatment NOT COMPLETED	16
3 Months Off-treatment STARTED	29
3 Months Off-treatment COMPLETED	28
3 Months Off-treatment NOT COMPLETED	1

Reasons for withdrawal

Measure	Triheptanoin This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
6 Months on Treatment Protocol non-compliance	7
6 Months on Treatment Adverse Event	4
6 Months on Treatment Tried alternative treatment	2
6 Months on Treatment Lost to Follow-up	2
6 Months on Treatment Personal reasons	1
3 Months Off-treatment Parent unable to travel	1

Baseline Characteristics

Diet Treatment Glucose Transporter Type 1 Deficiency (G1D)

Baseline characteristics by cohort

Measure	Triheptanoin n=45 Participants This is a single arm study.
Age, Continuous	9.53 years STANDARD_DEVIATION 5.07 • n=5 Participants
Sex: Female, Male Female	29 Participants n=5 Participants
Sex: Female, Male Male	16 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	13 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	32 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants

PRIMARY outcome

Timeframe: Change post 6 months of treatment

Population: Although 29 patients completed the 6-month treatment phase, some patients were unable to perform the test due to cognitive or physical impairment. The analysis population comprises of participants who were present at the time of testing and were able to comprehend and perform the test.

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.

Outcome measures

Measure	Triheptanoin n=16 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Neuropsychological Score of Sustained Attention	11 Participants

PRIMARY outcome

Timeframe: Change after 3 months off treatment

Population: Although 28 patients completed the 3-month treatment phase, some patients were unable to perform the test due to cognitive or physical impairment. The analysis population comprises of participants who were present at the time of testing and were able to comprehend and perform the test.

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.

Outcome measures

Measure	Triheptanoin n=15 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Neuropsychological Score of Sustained Attention	14 Participants

PRIMARY outcome

Timeframe: Change post 6 months of treatment

Population: Some patients were unable to perform the test due to cognitive, physical impairment or underdeveloped vocabulary skills. The analysis population comprises of participants who were present at the time of testing and were able to comprehend and perform the test.

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.

Outcome measures

Measure	Triheptanoin n=17 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Neuropsychological Score of Working Memory Index Scale (WMI)	7 Participants

PRIMARY outcome

Timeframe: Change after 3 months off-treatment

Population: Some patients were unable to perform the test due to cognitive, physical impairment or underdeveloped vocabulary skills. The analysis population comprises of participants who were present at the time of testing and were able to comprehend and perform the test.

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.

Outcome measures

Measure	Triheptanoin n=15 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Neuropsychological Score of Working Memory Index Scale (WMI)	5 Participants

PRIMARY outcome

Timeframe: Change post 6 months of treatment

Population: Some patients were cognitively unable to perform or comprehend the test. The analysis population comprises of participants who were present at the time of testing and were able to comprehend and perform the test.

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.

Outcome measures

Measure	Triheptanoin n=15 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Neuropsychological Score of Processing Speed Index (PSI)	6 Participants

PRIMARY outcome

Timeframe: Change after 3 months off-treatment

Population: Some patients were cognitively unable to perform or comprehend the test. The analysis population comprises of participants who were present at the time of testing and were able to comprehend and perform the test.

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.

Outcome measures

Measure	Triheptanoin n=13 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Neuropsychological Score of Processing Speed Index (PSI)	7 Participants

SECONDARY outcome

Timeframe: Change post 6 months of treatment

Population: Out of 45 enrolled, 29 patients completed the 6 month treatment period

The number of generalized spike wave (GSW) activity and bursts were extracted from the patient EEGs. GSW and bursts per hour was calculated. A decrease in the spike wave and burst indicated an improvement. The number of patients that displayed a decrease in GSW and burst per hour after 6 months of treatment in noted here.

Outcome measures

Measure	Triheptanoin n=29 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
EEG Changes: Generalized Spike Wave Activity and Burst GSW/hr	10 Participants
EEG Changes: Generalized Spike Wave Activity and Burst Bursts/hr	7 Participants

SECONDARY outcome

Timeframe: Change after 3 months off-treatment

Population: Out of 29 patients who completed the treatment period, 28 returned for the 3 month off-treatment visit.

The number of generalized spike wave (GSW) activity and bursts were extracted from the patient EEGs. GSW and bursts per hour was calculated. A decrease in the spike wave and burst indicated an improvement. 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 GSW and burst per hour (towards baseline) after 3 months off treatment as compared to 6 months on treatment is noted here.

Outcome measures

Measure	Triheptanoin n=28 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
EEG Changes: Generalized Spike Wave Activity and Burst Bursts/hr	11 Participants
EEG Changes: Generalized Spike Wave Activity and Burst GSW/hr	13 Participants

SECONDARY outcome

Timeframe: Change post 6 months of treatment

Population: Although 29 patients completed the study, some patients were unable to perform the test due to physical impairment and inability to comprehend the task. Here, the number of participants analyzed reflects the total number of patients that were present at the test and were able to complete it.

Ataxia is scored as per the Brief ataxia rating scale (BARS) - a modified form of the International Cooperative Ataxia Rating Scale (ICARS). The possible range for the scores is from 0 (normal, no ataxia) to 30 (severe ataxia). A decrease in the BARS score indicates an improvement in the ataxia symptoms. The number of participants that showed a decrease in BARS score after 6 months of intervention is reported here.

Outcome measures

Measure	Triheptanoin n=27 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Brief Ataxia Rating Scale	13 Participants

SECONDARY outcome

Timeframe: Change after 3 months off treatment

Population: Although 28 patients completed the off-treatment phase of study, some patients were unable to perform the test due to physical impairment and inability to comprehend the task. Here, the number of participants analyzed reflects the total number of patients that were present at the test and were able to comprehend it.

Ataxia is scored as per the Brief ataxia rating scale (BARS) - a modified form of the International Cooperative Ataxia Rating Scale (ICARS). The possible range for the scores is from 0 (normal, no ataxia) to 30 (severe ataxia). A decrease in the BARS score indicates an improvement in the ataxia symptoms. 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 participants that showed a subsequent increase in BARS score (towards baseline) after the of 3 months of no treatment as compared to 6 months on treatment are recorded here.

Outcome measures

Measure	Triheptanoin n=26 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Brief Ataxia Rating Scale	11 Participants

SECONDARY outcome

Timeframe: Change post 6 months of treatment

Population: Out of the 45 patients enrolled, 29 completed the 6 month treatment phase.

The Clinical global impression - Severity (CGI-S) scale is used to evaluate the illness severity where the scores range from 1 (very much improved) through to 7 (very much worse). A decrease in the CGI-S score indicates a decrease in illness severity. The number of participants that showed a decrease in CGI-S score after 6 months of intervention as compared to baseline is reported here.

Outcome measures

Measure	Triheptanoin n=29 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Clinical Global Impression Severity Scale	10 Participants

SECONDARY outcome

Timeframe: Change after 3 months off-treatment

Population: Out of the 29 patients that completed the treatment phase, 28 completed the following 3 month off-treatment phase. The assessment was incomplete for one patient due to inability to report symptoms.

The Clinical global impression - Severity (CGI-S) scale is used to evaluate the illness severity where the scores range from 1 (very much improved) through to 7 (very much worse). A decrease in the CGI-S score indicates a decrease in illness severity. The off-treatment period of 3 months was designed to study whether the impact of treatment persists or goes back to baseline. The number of participants that showed an increase in CGI-S score (towards baseline) after 3 months off treatment as compared to 6 months on treatment is reported

Outcome measures

Measure	Triheptanoin n=27 Participants This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Clinical Global Impression Severity Scale	9 Participants

Adverse Events

Triheptanoin

Serious events: 0 serious events

Other events: 41 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Measure	Triheptanoin n=45 participants at risk This is a single arm study. Patients diagnosed with G1D were enrolled in the study. They received the triheptanoin oil treatment dosed at 45% of the participant's daily caloric intake, divided into 4 doses per day. This intervention was administered for 6 months followed by a 3 month off intervention period.
Gastrointestinal disorders Mild nausea	20.0% 9/45 • 9 months
Gastrointestinal disorders Mild vomiting	48.9% 22/45 • 9 months
Gastrointestinal disorders Diarrhea	64.4% 29/45 • 9 months
Gastrointestinal disorders Upset stomach	22.2% 10/45 • 9 months
General disorders Stomach pain or cramping	22.2% 10/45 • 9 months
Gastrointestinal disorders Acid reflux	4.4% 2/45 • 9 months
General disorders Fatigue	8.9% 4/45 • 9 months
Gastrointestinal disorders Constipation	4.4% 2/45 • 9 months
Nervous system disorders Seizure	15.6% 7/45 • 9 months
General disorders Hypoglycemia	4.4% 2/45 • 9 months
General disorders Loss of appetite	6.7% 3/45 • 9 months

Additional Information

Dr. Juan Pascual

Weill Cornell Medicine

Phone: (212) 746-3278

Email: jup9003@med.cornell.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place