An observational study in Glycogen Storage Disease Type Ia, sponsored by Ultragenyx Pharmaceutical Inc. Recruiting at 19 sites in 9 countries. Open to participants aged 2 Years and older. Per ClinicalTrials.gov, last updated 2026-10-14.
Sponsored by Ultragenyx Pharmaceutical Inc · Observational
The main objective of this observational study is to evaluate the long-term safety and effectiveness of DTX401 for at least 10 years after DTX401 administration.
The DTX401-CL401 Disease Monitoring Program (DMP) is a prospective, multicenter, long-term observational study to follow up participants with GSDIa for at least 10 years after the administration of DTX401.
361 studies on the registry are indexed under Glucose Metabolism Disorders; 38 are open to participants now.
This study's planned enrollment of 140 is above the median of 87 across 47 observational studies indexed under Glucose Metabolism Disorders.
Browse Glucose Metabolism Disorders studies →Ultragenyx Pharmaceutical Inc is the lead sponsor of 63 studies on the registry; 8 are open to participants now.
Of its 16 completed or terminated interventional studies of FDA-regulated products, 12 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
All participants who received DTX401 in a qualifying clinical study will be expected and asked to participate in the DMP upon completion or early termination (ET) from the parent study, as required by regulatory agencies for all gene therapy studies.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Patient who had:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients administered DTX401(pariglasgene brecaparvovec), full or partial dose, in prior clinical study involving DTX401
Other: No Intervention
Patients administered prescribed DTX401(pariglasgene brecaparvovec), full or partial dose, in a post-marketing setting
Other: No Intervention
No investigational/study product will be administered in this DMP.
Incidence and Severity of Serious Adverse Events (SAEs) Assessed as Related to DTX401 by the Investigator
Time frame: 10 Years
Incidence, Relationship, Severity and Seriousness of Adverse Events of Special Interest (AESIs) for Adeno-Associated Virus (AAV) Therapies
Time frame: 10 Years
Incidence of Pregnancy in Patients Treated with DTX401 or Patient's Partner
Time frame: 10 Years
Outcomes of Pregnancy in Patients Treated with DTX401 or Patient's Partner
Time frame: 10 Years
Incidence and Severity of SAEs of Infusion-Related Reactions Including Hypersensitivity (Group 2 only)
Time frame: 1 Year
Incidence and Severity of SAEs Assessed by the Investigator as Related to Concomitant Immunomodulatory Therapies (Group 2 only)
Time frame: 1 Year
Percent Change Over Time from Baseline in Total Cornstarch Intake
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Frequency of Cornstarch Intake
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Number of Nighttime Awakenings for Cornstarch
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Dependance on Continuous Overnight Tube Feeding for Exogenous Glucose Delivery
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Daily Dietary Intake of Foods, Beverages, and Medical Foods/Formulas (Non-Cornstarch)
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Daytime and Nighttime Percentage of Glucose Values During the 2 Weeks Leading Up to the Assessment Visits
The following ranges will be assessed: \< 54 mg/dL, \< 60 mg/dL, \< 70 mg/dL, 70-120 mg/dL, \> 120 mg/dL
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Total Number of Hypoglycemic Events on Continuous Glucose Monitoring (CGM) During the 2 Weeks Leading Up to the Assessment Visits
The following ranges will be assessed: \< 54 mg/dL, \< 70 mg/dL
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Total Duration of Hypoglycemic Events on CGM During the 2 Weeks Leading Up to the Assessment Visits
The following ranges will be assessed: \< 54 mg/dL, \< 70 mg/dL
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Real-World Overnight Fasting Tolerance
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Metabolic and GSDIa Related Parameters: Height
Time frame: 10 Years
Change from Baseline Over Time in Metabolic and GSDIa Related Parameters: Weight
Time frame: 10 Years
Change from Baseline Over Time in Metabolic and GSDIa Related Parameters: Body Mass Index (BMI)
Time frame: 10 Years
Number of Participants with Clinically Significant Laboratory Values
Time frame: 10 Years
Frequency of Major Clinical Events (MCEs)
Time frame: 10 Years
Frequency of MCEs from Review of Medical Records
Time frame: 10 Years
Change from Baseline in Patient Experience Clinical Interview
Time frame: Baseline, Up to 10 Years
Change from Baseline in European Quality of Life 5 Dimensions 5 Levels (EQ-5D-5L) Questionnaire Score
Time frame: Baseline, Up to 1 Year
Change from Baseline in European Quality of Life 5 Dimensions Youth (EQ-5D-Y) Questionnaire Score
Time frame: Baseline, Up to 1 Year
Change from Baseline Over Time in Annual Number of GSDIa Related Hospitalizations, Emergency Room Visits, Outpatient Visits, and Hospital Days
Time frame: Baseline, Up to 10 Years
Change from Baseline Over Time in Missed Work/School Days in the Past 3 Months
Time frame: Baseline, Up to 10 Years
Change from Baseline in Work/School Productivity Rating
Time frame: Baseline, Up to 10 Years
Change from Baseline in Employment
Time frame: Baseline, Up to 10 Years
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Glucose Metabolism Disorders →
Ultragenyx Pharmaceutical Inc →