An observational study in N-acetylglutamate Synthase (NAGS) Deficiency, sponsored by Nicholas Ah Mew. Recruiting at 3 sites in United States. Per ClinicalTrials.gov, last updated 2024-02-07.
Sponsored by Nicholas Ah Mew · Observational
Among 40 studies in Urea Cycle Disorders, Inborn with a site in United States — 9 open to participants now, 12 under way, 1 of them phase 3. Urea Cycle Disorders, Inborn · United States.
Among the 40 studies in Urea Cycle Disorders, Inborn with a site in United States, this one is the 10th largest by planned enrollment of the 16 observational ones that give a count, is one of 2 that started in 2012, is one of 16 observational ones, reaches primary completion later than 3 of the 11 other live ones, and was the 23rd registered.
66 studies on the registry are indexed under Urea Cycle Disorders, Inborn; 14 are open to participants now.
Browse Urea Cycle Disorders, Inborn studies →9 of the 40 studies in Urea Cycle Disorders, Inborn with a site in United States are open now. Recruiting first, the newest first:
Rebecca Ahrens-Nicklas · Sites in United States
Ages 24 hrs–5 yrs
St. Jude Children's Research Hospital · Sites in United States
Ages 16–40 · Healthy volunteers
Sequitur Health Corp. · Sites in United States
Ages 12+
iECURE, Inc. · Sites in United States, France, United Kingdom
Ages 7 mo–15 mo
Baylor College of Medicine · Sites in United States
A study can be open while its sites in United States have not opened yet or have stopped. Only those recruiting at a site in United States →
Of the 12 Urea Cycle Disorders, Inborn studies recruiting now, 5 (42%) set no upper age limit and 7 (58%) stop at 75 or younger; 11 take children under 18; 4 take healthy volunteers.
This study: all sexes · no healthy volunteers.
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40 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 6 · Phase 2 9 · Phase 3 4 · Phase 4 3
First in 1999; this study’s year is marked. 2 started in 2012.
This study's planned enrollment of 30 is below the median of 46 across 23 observational studies indexed under Urea Cycle Disorders, Inborn.
Median enrollment 16 across the 24 interventional studies, 51 across the 16 observational. Of the 27 that completed or were terminated, 16 (59%) have results posted.
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18 of 40 have an industry lead sponsor. The 10 most frequent:
Nicholas Ah Mew is the lead sponsor of 2 studies on the registry; 1 is open to participants now.
Nicholas Ah Mew has 2 studies filed under Urea Cycle Disorders, Inborn — fewer than ten, so there is no comparison to draw.
2 of the studies in Urea Cycle Disorders, Inborn with a site in United States that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT04612764Baylor College of MedicineLiver Disease in Urea Cycle Disorders | 2026-12-31 |
| NCT06953505Sequitur Health Corp.At Home Ammonia Monitoring of Inborn Errors of Ammonia Metabolism | 2027-07 |
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Among the 40 studies in Urea Cycle Disorders, Inborn with a site in United States, from their registry updates:
Nothing recorded among them since 2026-09-25.
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The purpose of this study is to conduct post-marketing surveillance of carglumic acid (Carbaglu) to obtain long-term clinical safety information. Carglumic acid was approved by the United States Food and Drug Administration (FDA) for treatment of acute hyperammonemia due to N-acetylglutamate synthase (NAGS) deficiency. Much of the FDA-required data is already collected through the Longitudinal Study of Urea Cycle Disorders (RDCRN Protocol #5101). This study will collect additional data on adverse events (interim events), adverse reactions, pregnancy, and fetal outcomes.
Among the urea cycle disorders, N-acetylglutamate synthase (NAGS) deficiency is the rarest type. In 2010, carglumic acid (Carabglu) was approved by the United States Food and Drug Administration (FDA) "as an adjunctive therapy for the treatment of acute hyperammonemia due to the deficiency of the hepatic enzyme NAGS, and as maintenance therapy for chronic hyperammonemia due to NAGS deficiency." As post-marketing requirements, the US FDA requests that Orphan Europe (OE) conduct:
1604-2: A registry of patients, with NAGS deficiency being treated with carglumic acid to obtain long-term clinical safety information. Data will include patient demographics, details of treatment with carglumic acid, other therapies for hyperammonemia, dietary protein management, clinical status, neurocognitive and psychomotor status, growth and development status, and adverse events. Information from this registry is submitted to the FDA annually (in annual reports) with a final report submitted at 15 years post-approval.
1604-3: A study of the effects of carglumic acid on pregnancy and fetal outcomes. This study can be performed as a sub-study within the registry for all patients with NAGS deficiency. Information on pregnancy and fetal outcomes should be submitted annually (in annual reports) with a final report submission at 15 years post-approval.
This patient registry or surveillance protocol will be facilitated by collaboration with the existing National Institutes of Health (NIH) sponsored Urea Cycle Disorders Consortium (UCDC) Longitudinal Study of Urea Cycle Disorders (RDCRN Protocol #5101) (including NAGS deficiency) in the United States. The Longitudinal Study is sponsored by the NIH and other philanthropic sources. It is an academically governed network with the objective to conduct a longitudinal multidisciplinary investigation of the natural history, morbidity and mortality in people with UCD. It therefore aims to collect data on all patients with NAGS deficiency in the US. Measures in the Longitudinal Study are compatible with a Carbaglu post-marketing study including: developmental outcome, medical history, interval medical history, adverse events (interim events), pregnancy history, physical exam, vital signs, laboratory evaluation, dietary history, and medication records. Additional data on drug related adverse events and pregnancy outcomes will is collected for OE for FDA reporting.
Confirmed diagnosis of NAGS deficiency or suspicion of NAGS deficiency, taking Carbaglu for the treatment of NAGS, and enrolled in the Longitudinal Study of Urea Cycle Disorders (RDCRN protocol #5101)
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.
Exclusion Criteria:
Carbaglu related adverse events and adverse reactions
The primary outcome measure is to monitor adverse events and adverse reactions, which will be reported to the FDA to fulfill post-marketing surveillance requirements.
Time frame: 15 years
Number of hyperammonemic events
The number of hyperammonemic events (ammonia \> 100 umol/L) will be monitored in participants taking Carbaglu to ensure there are no significant adverse changes
Time frame: 15 years
IQ
IQ will be monitored in participants taking Carbaglu to ensure there are no significant adverse changes
Time frame: 15 years
Height
Height (cm) will be monitored in participants taking Carbaglu to ensure there are no significant adverse changes
Time frame: 15 years
Weight
Weight (kg) will be monitored in participants taking Carbaglu to ensure there are no significant adverse changes
Time frame: 15 years
Abnormal physical and neurological findings
Any abnormal physical and neurological findings reported will be investigated as potential adverse reactions/adverse events (see primary outcome measure). Investigators conducts a review of systems and indicates whether findings are normal, abnormal or not assessed. Each abnormal finding is coded using SNOMED codes.
Time frame: 15 years
Plan to share: No — This is a post-marketing surveillance study being performed so that Orphan Europe (OE) can meet its post FDA approval reporting obligations. Data will be shared with OE who will then report to the FDA. There are no other plans to make this data available to other researchers.
The record gives a start of Apr 2012, a primary completion of Jul 2026 and a completion of Jan 2027. It does not say whether these dates are actual or estimated.
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Urea Cycle Disorders, Inborn →
Nicholas Ah Mew