Clinical trial NCT06852612: Dietary Treatment Strategies and Metabolic Control in Glycogen Storage Disease Type I
Official title: Dietary Treatment Strategies and Metabolic Control in Glycogen Storage Disease Type I (GSD-DIET)
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Glycogen Storage Disease Type I
Keywords: Gsd1
Metabolism
Fructose
Galactose
Lead sponsor: Insel Gruppe AG, University Hospital Bern
Sponsor class: OTHER
Collaborators: name: University of Zurich
name: University Hospital Freiburg
name: University Hospital Heidelberg
name: Medical University Innsbruck
First posted: 2025-02-28
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: The present project will specifically assess metabolic effects of dietary interventions with controlled intake of fructose and fructose/galactose in GSDI, with the aim to provide evidence whether relaxed dietary restrictions of fructose and galactose may be justified in treatment recommendations at least for adults, which would considerably enlarge food choice in everyday life of the patients with an expected positive impact on the quality of life of patients with this rare disorder.

Detailed description: To assess relaxed restriction of fructose and fructose/galactose intake on secondary metabolic alterations in GSDI, (i) by looking at the traditional parameters for assessing metabolic control in clinical chemistry (lactate, triglycerides, uric acid), and (ii) by using a broad analytical approach relying on targeted metabolomics/lipidomics.

It is hypothesized that relaxed restrictions on the intake of fructose and/or galactose as part of the diet in everyday life may lead to an increase in blood lactate levels (=primary outcome), triglycerides, and uric acid to a certain degree compared to baseline. However, this increase is expected to remain within a range that is not clinically relevant for adult patients, especially when fructose/galactose intake is not excessive and stays within the usual daily allowances for healthy individuals, as planned in this study.

Eligibility criteria: Inclusion Criteria:

* Genetically and/or enzymatically confirmed diagnosis of GSDI (GSDIa or GSDIb)
* Male or female ≥ 18y
* Restriction of fructose intake in usual dietary treatment
* Written informed consent

Exclusion Criteria:

* Non-compliance with routine dietary treatment
* Pregnancy or lactation
* Liver transplant
* Recurrent hospitalisations due to metabolic decompensation within the last 12 months
* Severe chronic kidney disease with glomerular filtration rate (GFR) \< 30 ml/min
* For GSDIb: Severe, uncontrolled symptomatic inflammatory bowel disease

Primary outcomes:
measure: Change in lactate during the dietary intervention compared to baseline under the usual diet
timeFrame: 4 Weeks
Secondary outcomes:
measure: Change in plasma triglycerides during the dietary intervention compared to baseline (as parameters traditionally measured together with lactate to estimate overall metabolic control)
timeFrame: 4 Weeks
measure: Change in plasma uric acid during the dietary intervention compared to baseline (as parameters traditionally measured together with lactate to estimate overall metabolic control)
timeFrame: 4 Weeks
measure: Plasma metabolite changes in targeted metabolomics during the dietary intervention compared to baseline measurements.
timeFrame: 4 Weeks
measure: Plasma metabolite changes in targeted lipidomics during the dietary intervention compared to baseline measurements.
timeFrame: 4 Weeks
Other outcomes:
Locations:
city: Bern
country: Switzerland
facility: Department of Diabetes, Endocrinology, Nutritional Medicine and Metabolism, Inselspital, Bern University Hospital
Study officials:
affiliation: Department of Diabetes, Endocrinology, Nutritional Medicine and Metabolism
name: Michel Hochuli, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References: