Glycogen Storage Disease VINCT04454216
GSD VI and GSD IX Natural History
An observational study of Glycogen Storage Disease VI and GLYCOGEN STORAGE DISEASE IXa1, run by Duke University at 1 site in United States.
Trial summary
Collection and review of clinical information related to Glycogen Storage Disease Type VI (GSD VI) OR Glycogen Storage Disease Type IX (GSD IX) generated during clinic visits. Read more about this study
- Who is it for?
- Ages 0 to 90 years
- Conditions the study is for
- Glycogen Storage Disease VI, GLYCOGEN STORAGE DISEASE IXa1, GLYCOGEN STORAGE DISEASE IXa2
- How many people
- 400 participants
- Where
- 1 siteUnited States
- Study dates
- 18 Sep 2020to 1 Jan 2030
- How long will I take part?
- 20 Years
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 0 to 90 years
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: All patients with GSD VI or GSD IX, regardless of gender or ethnicity, are eligible for enrollment.
Who may be able to join
- Diagnosis of GSD VI or GSD IX via:
- Two variants in the PYGL, PHKA1, PHKA2, PHKG1, PHKG2, or PHKB gene (or one variant with evidence of disease). Note: for males, one variant in the PHKA1 or PHKA2 gene is sufficient for inclusion.
- Deficient GP activity or PhK activity per enzymology
- Histology as confirmed by clinician
- Pregnant women with a diagnosis of GSD VI or GSD IX will be included
- Able to provide informed consent for self (adults) or affected individual (minor or adults with a legally authorized representative)
- Able to provide consent for release of medical records
Who cannot join
- Unable to provide informed consent for participation for one's self or by legally authorized representative/legal guardian/parent
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Duke University
Durham, North Carolina, 27710
Rebecca L Koch, PhD, RDN, 919-681-8823, rebecca.koch@duke.edu
Nisha Dalal, M.S. CCC-SLP, 919-668-3107, nisha.dalal@duke.edu
About this study
Collection and review of clinical information related to Glycogen Storage Disease Type VI (GSD VI) OR Glycogen Storage Disease Type IX (GSD IX) generated during clinic visits.
Read the detailed description
This natural history study will serve as a repository of clinical, laboratory, and biochemical information on individuals with GSD VI or GSD IX. This information will allow a more definitive description of glycogen phosphorylase (GP) and phosphorylase kinase (PhK) deficiency to be developed, which will permit development of treatment strategies for these diseases.
Duke will be the only site where this study takes place. However, since these are rare disorders, participants who receive care at other institutions will be included. The investigators will collect retrospective data from patient charts on diagnosed individuals, as far back as necessary to capture the clinical course of the disorder. Prospective data collected from patient charts after enrollment will be captured as well. Participant's medical records will be continually reviewed for the duration of the study.
Data will be collected from medical records and will only pertain to clinically relevant information, including, but not limited to: demographic and diagnostic information, tissue biopsy results, medical and family history, review of systems, imaging studies, results of liver and/or muscle testing, and urine and blood laboratory results.
- Conditions
- Glycogen Storage Disease VI, GLYCOGEN STORAGE DISEASE IXa1, GLYCOGEN STORAGE DISEASE IXa2, Glycogen Storage Disease IXB, Glycogen Storage Disease IXC, GSD 9 (All Subtypes)
- Being tested
- No intervention
- Medical subject headings
- Glycogen Storage Disease Type VI, Glycogen Storage Disease, Type IXA2, Glycogen Storage Disease IXB, Glycogen Storage Disease IXC
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
No interventionOther
This is an observational study that consists of data abstraction from patient medical records.
What is being measured
The primary outcome is the main question the study is designed to answer.
Progression of disease confirmed by medical record review
Measured: through study completion, an average of 10 years
Serum biotinidase activity
Measured: through study completion, an average of 10 years
Number of genotypes presented
Measured: through study completion, an average of 10 years
Number of phenotypes presented
Measured: through study completion, an average of 10 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Jul 2020
- Study start18 Sep 2020
- Primary completion1 Jan 2030 (estimated)
- Study completion1 Jan 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Glycogen Storage Disease VIStudies of the same condition, open and under way.
- More trials run by Duke UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Other
- Enrolment
- 400 participants (estimated)
- Target duration
- 20 Years
Sponsor and investigators
- Lead sponsor
- Duke University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Priya Kishnani, MD, Principal investigator, Duke University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04454216
- Sponsor's protocol ID
- Pro00104116
- Status last verified
- May 2026
- First submitted
- 29 Jun 2020
- Last updated
- 5 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Koch RL, Fares AH, Cocanougher BT, Lim J, Haijer-Schreuder AB, Derks TGJ, Grunert SC, Sharma R, Jones KA, Kishnani PS. PHKA1-associated phosphorylase kinase deficiency: a monogenic disorder of exercise intolerance and myalgia. NPJ Genom Med. 2025 Nov 10;10(1):71. doi: 10.1038/s41525-025-00527-y.
PubMed 41213961
Study at a glance
From the registry record, last updated by the sponsor on 5 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- GSD VI and GSD IX Natural History
- ClinicalTrials.gov ID
- NCT04454216
- Acronym / sponsor ID
- Pro00104116
- Conditions
- Glycogen Storage Disease VI, GLYCOGEN STORAGE DISEASE IXa1, GLYCOGEN STORAGE DISEASE IXa2, Glycogen Storage Disease IXB, Glycogen Storage Disease IXC, GSD 9 (All Subtypes)
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 400 participants (estimated)
- Lead sponsor
- Duke UniversityUniversity, hospital or other
- Study start
- 18 Sep 2020 (actual)
- Primary completion
- 1 Jan 2030 (estimated)
- Study completion
- 1 Jan 2030 (estimated)
- First posted
- 1 Jul 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Collection and review of clinical information related to Glycogen Storage Disease Type VI (GSD VI) OR Glycogen Storage Disease Type IX (GSD IX) generated during clinic visits.
Detailed description
This natural history study will serve as a repository of clinical, laboratory, and biochemical information on individuals with GSD VI or GSD IX. This information will allow a more definitive description of glycogen phosphorylase (GP) and phosphorylase kinase (PhK) deficiency to be developed, which will permit development of treatment strategies for these diseases.
Duke will be the only site where this study takes place. However, since these are rare disorders, participants who receive care at other institutions will be included. The investigators will collect retrospective data from patient charts on diagnosed individuals, as far back as necessary to capture the clinical course of the disorder. Prospective data collected from patient charts after enrollment will be captured as well. Participant's medical records will be continually reviewed for the duration of the study.
Data will be collected from medical records and will only pertain to clinically relevant information, including, but not limited to: demographic and diagnostic information, tissue biopsy results, medical and family history, review of systems, imaging studies, results of liver and/or muscle testing, and urine and blood laboratory results.
Study design
- Observational model
- Cohort
- Time perspective
- Other
- Target follow-up
- 20 Years
Who may qualify
- Ages
- 0 to 90 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
- Study population
- All patients with GSD VI or GSD IX, regardless of gender or ethnicity, are eligible for enrollment.
Key inclusion criteria (7 listed)
- Diagnosis of GSD VI or GSD IX via:
- Pregnant women with a diagnosis of GSD VI or GSD IX will be included
- Able to provide informed consent for self (adults) or affected individual (minor or adults with a legally authorized representative)
- Able to provide consent for release of medical records
Key exclusion criteria (1 listed)
- Unable to provide informed consent for participation for one's self or by legally authorized representative/legal guardian/parent
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| No interventionThis is an observational study that consists of data abstraction from patient medical records. | Other | – |
Primary outcome
Progression of disease confirmed by medical record review
Time frame: through study completion, an average of 10 years
Serum biotinidase activity
Time frame: through study completion, an average of 10 years
Number of genotypes presented
Time frame: through study completion, an average of 10 years
Number of phenotypes presented
Time frame: through study completion, an average of 10 years
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 May 2026.
- Derived from this study: PubMed 41213961Koch RL, Fares AH, Cocanougher BT, Lim J, Haijer-Schreuder AB, Derks TGJ, Grunert SC, Sharma R, Jones KA, Kishnani PS. PHKA1-associated phosphorylase kinase deficiency: a monogenic disorder of exercise intolerance and myalgia. NPJ Genom Med. 2025 Nov 10;10(1):71. doi: 10.1038/s41525-025-00527-y.
- Individual participant dataSharing planned: No
Related trials for Glycogen Storage Disease VI
Active, not recruitingObservational study
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Spinal Muscular Atrophy, Fragile X Syndrome
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Priya Kishnani, MD principal investigator
Duke University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Glycogen Storage Disease VI and GLYCOGEN STORAGE DISEASE IXa1, run by Duke University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 5 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Rebecca L Koch, PhD, RDN (919-681-8823, rebecca.koch@duke.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Progression of disease confirmed by medical record review (time frame: through study completion, an average of 10 years). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04454216, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 May 2026.