NCT07432490

Brief Summary

This is a single-center, randomized, double-blind, placebo-controlled, cross-over study to evaluate the efficacy and safety of L-fucose supplementation in subjects with GLUT1 deficiency syndrome (GLUT1DS).

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
16

participants targeted

Target at below P25 for phase_2

Timeline
14mo left

Started May 2026

Shorter than P25 for phase_2

Geographic Reach
1 country

1 active site

Status
recruiting

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

Study Progress10%
May 2026Aug 2027

First Submitted

Initial submission to the registry

February 14, 2026

Completed
11 days until next milestone

First Posted

Study publicly available on registry

February 25, 2026

Completed
2 months until next milestone

Study Start

First participant enrolled

May 5, 2026

Completed
1.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

July 1, 2027

Expected
1 month until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2027

Last Updated

May 13, 2026

Status Verified

May 1, 2026

Enrollment Period

1.2 years

First QC Date

February 14, 2026

Last Update Submit

May 8, 2026

Conditions

Glut1 DeficiencyGLUT1DS1

Keywords

GLUT1 DeficiencyGLUT1 Deficiency SyndromeGLUT1DSSLC2A1FucoseL-fucose

Outcome Measures

Primary Outcomes (18)

  • SARA (Scale for the Assessment and Rating of Ataxia) Score

    Severity of ataxia and cerebellar involvement as measured by the SARA clinical scales. This score ranges from 0 (no ataxia) to 40 (most severe ataxia)

    24 weeks

  • Modified SARA (Scale for the Assessment and Rating of Ataxia) score

    This modified score suggested by the FDA rates severity of ataxia from 0 (no ataxia) to 16 (most severe ataxia)

    24 weeks

  • ICARS (International Cooperative Ataxia Rating Scale) Score

    This scale score the severity of ataxia and other cerebellar findings from 0 (no compromise) to 100 (maximal impairment)

    24 weeks

  • Safety labs: hemoglobin

    Changes in levels of hemoglobin in g/dL

    24 weeks

  • Safety labs: white blood cell count

    Changes in white blood cell counts as measured in cells/mm3

    24 weeks

  • Safety labs: platelet count

    Changes in platelet counts measured as cells/mm3

    24 weeks

  • Safety labs: lactate dehydrogenase

    Changes in lactate dehydrogenase (LDH) levels measured as U/L

    24 weeks

  • Safety labs: alanine-aminotransferase

    Changes in alanine-aminotransferase (ALT) measured as U/L

    24 weeks

  • Safety labs: aspartate-aminotransferase

    Changes in aspartate-aminotransferase (AST) measured as U/L

    24 weeks

  • Safety labs: gamma-glutamyltransferase

    Changes in gamma-glutamyltransferase (GGT) measured as U/L

    24 weeks

  • Safety labs: serum creatinine

    Changes in serum creatinine measured as mg/dL

    24 weeks

  • Safety labs: blood urea nitrogen

    Changes in blood urea nitrogen (BUN) measured as mg/dL

    24 weeks

  • Safety labs: serum sodium

    Changes in serum sodium (Na) as measured in mmol/L

    24 weeks

  • Safety labs: serum potassium

    Changes in serum potassium (K) measured as mmol/L

    24 weeks

  • Safety labs: serum chloride

    Changes in serum chloride (Cl) measured as mmol/L

    24 weeks

  • Safety labs: serum calcium

    Changes in serum calcium (Ca) measured as mmol/L

    24 weeks

  • Safety labs: serum bicarbonate

    Changes in serum bicarbonate/carbonate measured as mmol/L

    24 weeks

  • Subject-reported adverse events

    Rate and character (including standardized severity) of adverse events as reported by the study subjects

    24 weeks

Secondary Outcomes (6)

  • Severity of dysarthria

    24 weeks

  • Frequency and severity of migraines

    24 weeks

  • Frequency of paroxysmal exercise-induced dystonia

    24 weeks

  • Frequency of seizures

    24 weeks

  • World Health Organization Quality of Life (WHO-QoL) scale

    24 weeks

  • +1 more secondary outcomes

Study Arms (2)

L-fucose followed by placebo

ACTIVE COMPARATOR

L-fucose for 12 weeks, followed by placebo for 12 weeks.

Drug: L-fucoseOther: Placebo

Placebo followed by L-fucose

PLACEBO COMPARATOR

Placebo for 12 weeks, followed by L-fucose for 12 weeks.

Drug: L-fucoseOther: Placebo

Interventions

L-fucoseDRUG

L-fucose will be administered as 500 mg/kg to a maximum of 10 g three times per day by mouth.

Also known as: fucose
L-fucose followed by placeboPlacebo followed by L-fucose
PlaceboOTHER

Placebo will be composed of micro-cellulose powder with a small amount of Stevia for taste mimicking, to be taken at 500 mg/kg for a maximum of 10 g three times per day by mouth.

L-fucose followed by placeboPlacebo followed by L-fucose

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Age ≥ 18 years
  • Confirmed diagnosis of GLUT1DS, including at least 2 out of the following 3: molecular genetic testing showing a pathogenic or likely pathogenic variant in SLC2A1; documented hypoglycorrhachia with a CSF:blood glucose ratio ≤ 0.6; clinical features consistent with GLUT1DS (epilepsy, movement disorders, ataxia, intellectual disability, dysarthria)
  • Presence of ataxia

You may not qualify if:

  • Inability to swallow liquids
  • Change in neurological medications (either medication itself or medication dosages) in the past 90 days
  • Use of fucose- or mannose-containing supplements within one year of enrollment
  • Presence of hepatic, renal, hematological, or concomitant metabolic disorders, as assessed by the presence of a previous diagnosis of such disorders (for instance, chronic kidney disease, liver cirrhosis, diabetes mellitus) or by the following laboratory values, which will be considered if obtained clinically up to 90 days before enrollment (if this is not available, laboratory tests will be obtained prior to first study visit):
  • Any degree of hepatic impairment based on the Child-Pugh classification
  • eGFR (as measured by serum creatinine or cystatin C) \< 60 mg/min/1.73m2
  • Hemoglobin A1c \> 6.5%
  • Hemoglobin level below the lower limit of normal (LLN) for sex and age
  • Platelet counts below the LLN for sex and age
  • Subjects who are pregnant, breastfeeding, or planning to become pregnant within one year of enrollment
  • Enrollment in an investigational new drug trial for G1DS within one year of enrollment

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Oregon Health and Science University

Portland, Oregon, 97239, United States

RECRUITING

MeSH Terms

Conditions

Glut1 Deficiency Syndrome

Interventions

Fucose

Intervention Hierarchy (Ancestors)

Deoxy SugarsCarbohydrates

Study Officials

  • Rodrigo T. Starosta, MD, PhD

    Oregon Health and Science University

    STUDY DIRECTOR

Central Study Contacts

Celena Byerlee-Dixon

CONTACT

503-494-7004byerlee@ohsu.edu

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Assistant Professor

Study Record Dates

First Submitted

February 14, 2026

First Posted

February 25, 2026

Study Start

May 5, 2026

Primary Completion (Estimated)

July 1, 2027

Study Completion (Estimated)

August 1, 2027

Last Updated

May 13, 2026

Record last verified: 2026-05

Data Sharing

IPD Sharing
Will not share

Locations

US(1)