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Study to Evaluate 13 C Isotope Ratio Measurement for Urea Cycle Capacity Assessment

This study has been completed.
Information provided by:
Cytonet GmbH & Co. KG Identifier:
First received: October 26, 2009
Last updated: January 14, 2010
Last verified: January 2010

In this short-term study a method for the evaluation of the metabolic competency of the urea cycle in vivo will be assessed. In order to monitor the efficacy of new treatment options for patients with urea cycle disorders and to monitor the severity of the disease, a reliable and safe quantitative method for the measurement of the urea cycle flux is required.

Urea synthesis will be evaluated by administering sodium [1-13C]-acetate and measuring subsequent incorporation of [13C] label from Na-acetate into urea in healthy volunteers and asymptomatic subjects genetically disposed to urea cycle disorders.

Condition Intervention
Urea Cycle Disorders
Other: sodium [1-13C] acetate

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Diagnostic
Official Title: Pilot Feasibility Study in Healthy Subjects and Healthy Asymptomatic Subjects Genetically Disposed to Urea Cycle Disorders to Evaluate the Use of 13 C Isotope Ratio Measurement

Resource links provided by NLM:

Further study details as provided by Cytonet GmbH & Co. KG:

Primary Outcome Measures:
  • Increase of [13C]urea AUC in plasma following oral administration of [13C ]-sodium acetate over baseline

Secondary Outcome Measures:
  • Cmax of absolute [13C]urea in plasma

Enrollment: 10
Study Start Date: September 2009
Study Completion Date: December 2009
Primary Completion Date: November 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: sodium [1-13C] acetate Other: sodium [1-13C] acetate


Ages Eligible for Study:   18 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Group 1 + 2: Healthy subjects
  • Group 3: Healthy asymptomatic subjects genetically disposed to urea cycle disorders
  • All: age 18 to 50 years (adult)
  • Written informed consent

Exclusion Criteria:

  • Presence of acute infection
  • Participation in other clinical trials within 30 days prior to inclusion
  • Severe coagulopathy
  • Severe systemic or chronic disease
  • Pregnancy or lactation
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Please refer to this study by its identifier: NCT01002469

CRS Clinical Research Services Mönchengladbach GmbH
Mönchengladbach, Germany, 41061
Sponsors and Collaborators
Cytonet GmbH & Co. KG
Principal Investigator: Doris Neuenhofer, MD CRS Clinical Research Services Mönchengladbach GmbH
  More Information

Responsible Party: Heinz Kriegbaum, Cytonet GmbH & Co. KG Identifier: NCT01002469     History of Changes
Other Study ID Numbers: CCD07
Study First Received: October 26, 2009
Last Updated: January 14, 2010

Keywords provided by Cytonet GmbH & Co. KG:
isotope ratio measurement
urea cycle
13C acetate
Healthy adults

Additional relevant MeSH terms:
Urea Cycle Disorders, Inborn
Brain Diseases, Metabolic, Inborn
Brain Diseases, Metabolic
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Amino Acid Metabolism, Inborn Errors
Metabolism, Inborn Errors
Genetic Diseases, Inborn
Metabolic Diseases processed this record on May 25, 2017