French Observatory for Patients with Type 3 Glycogenosis
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- This is an observational study: the protocol does not assign a study treatment.
- Who it may be relevant to
- Registry conditions: Glycogen Storage Disease Type III. Basic parameters: No limits · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- France
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Overview
Glycogen storage disease type III (GSD-III) or Cori/Forbes disease, is caused by autosomal recessive mutations in the AGL gene, which codes for the glycogen debranching enzyme (GDE) involved in the release of glucose-1P from glycogen branches. Abnormal glycogen accumulation is responsible for frequent hypoglycaemia and symptoms in the liver and striated muscles (GSD-IIIa), although some patients present with liver involvement only (GSD-IIIb). In childhood, the phenotype is mainly characterised by hepatomegaly, short stature and hypoglycaemia, with minimal skeletal muscle involvement. While liver symptoms improve spontaneously around puberty, skeletal muscle weakness develops progressively in adulthood and becomes a major feature of GSD-IIIa. Currently, there is no treatment other than dietary management tailored to the individual to limit glycogen storage and avoid hypoglycaemia. The French GSD-III registry is a multicentre online registry dedicated to patients with type III glycogen storage disease followed in France. It has been approved by ethical and regulatory authorities. Its main inclusion criteria is the presence of a proven pathogenic AGL gene mutation and/or reduced glycogen debranching enzyme activity. The aims of the registry are to provide a tool for recording detailed diagnostic, metabolic, neurological, cardiac and biological data on French patients with GSD-III, so as to enable i) a precise natural history of the disease, ii) identification of the outcome measures most sensitive to disease progression, iii) assessment of the frequency of the various complications of the disease and iv) identification of prognostic factors.
Primary outcome measures
- Fasting period [Time frame: Through study completion, an average of 10 years]
Secondary outcome measures (1)
- 6MWT distance [Time frame: Through study completion, an average of 10 years]
Eligibility criteria
Inclusion criteria
- Patients with molecularly characterised Glycogen Storage Disease Type III
Exclusion criteria
- Patients diagnosed with GSD type 3 refusing to take part in the study
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Cohort
Study locations
France · 3 centers
- Aphp Antoine Beclere — Clamart
- CHU du Kremlin-Bicêtre — Le Kremlin-Bicêtre
- Institue of Myology — Paris
Publications
- Hogrel JY, Fer F, Ledoux I, Petit F, Darce-Bello M, Labrune P, Wahbi K, Habes D, Gardin A, Masingue M, Laforet P, Decostre V. Prospective gait analysis in patients from the French registry of glycogen storage disease type III: implications for clinical trials. J Neurol. 2026 May 4;273(5):301. doi: 10.1007/s00415-026-13793-2. PMID 42082675
Identifiers
NCT: NCT06616545 · GSD3 French Registry