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Metabolism of Ornithine Phenylacetate (OCERA OP)

This study is ongoing, but not recruiting participants.
Ocera Therapeutics
Information provided by (Responsible Party):
Marielle PKJ Engelen, PhD, Texas A&M University Identifier:
First received: May 16, 2017
Last updated: May 19, 2017
Last verified: May 2017
Intravenous infusion of stable tracers of ornithine, glutamine, glutamate, and glycine will be performed, and collect blood samples, urine samples, and muscle biopsies to evaluate the effect of a continuous oral intake of phenylacetate salt of ornithine (OP) on its metabolic fate.

Condition Intervention
Healthy Other: phenylacetate salt of ornithine

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Other
Official Title: Human Metabolism of Ornithine Phenylacetate: A Study in Healthy Volunteers

Resource links provided by NLM:

Further study details as provided by Marielle PKJ Engelen, PhD, Texas A&M University:

Primary Outcome Measures:
  • metabolism of ornithine phenylacetate to glutamate and glutamine [ Time Frame: 4 study days that are 8 hours each ]
    The incorporation of the N atoms of ORN into glutamate, and the quantitative contribution of both pathways will be traced, and when the enrichment of ORN and GLU is measured in muscle tissue, give an estimation of the importance of muscle OAT for this incorporation.

Enrollment: 20
Actual Study Start Date: February 2015
Estimated Study Completion Date: April 2018
Primary Completion Date: April 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: phenylacetate salt of ornithine
There are 4 study days of approximately 10 hours. Amino acid tracers (e.g., OP, PHE, TYR) will be provided via IV. The dosage of OP provided in this study 6 g in a period of 6 hours. 2 muscle biopsies will be completed on 2 of the study days.
Other: phenylacetate salt of ornithine

Detailed Description:
The study involves 1 screening visit of approximately 1 hour and 4 study days of approximately 10 hours. The subject will be asked to arrive in the fasted state on all study days. Fasting prior to screening is not required. On the screening day, body weight and height will be measured and Dual-energy X-ray absorptiometry (DXA) will be performed to measure body composition. After 4 hours subjects received a continuous intravenous infusion with OP in a dosage of 1 g /h. Next to the stable tracers provided to determine OP metabolism, stable tracers of phenylalanine (PHE) and tyrosine (TYR) may be provided to determine the effect of OP on protein metabolism at plasma and muscle tissue level. This required 2 muscle biopsies and on 2 study days 1 set of stable tracer pulses.

Ages Eligible for Study:   40 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion criteria healthy subjects:

  • Healthy male & female according to the investigator's or appointed staff's judgment
  • Age 40-70 years (to be comparable with patients with liver cirrhosis: average 54.1 +/- 9.4 years)

Exclusion Criteria

  • Metabolic diseases including diabetes and hepatic or renal disorders
  • Presence of acute illness or metabolically unstable chronic illness
  • Failure to give informed consent
  • (Possible) pregnancy
  • Any other condition according to the PI or nurse that would interfere with the study or safety of the patient or influence the results
  • Unwilling to stop taking nutritional protein supplements within 5 days before test day
  • History of hypo- or hyper-coagulation disorders, including use of a Coumadin derivative, history of deep venous thrombosis (DVT), or pulmonary embolism (PE) at any point in lifetime
  • Currently taking anti-thrombotics (i.e. medical indication) and cannot stop for 3-7 days prior to test days
  • Allergy to local anesthetic
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT03159390

United States, Texas
Texas A&M University-CTRAL
College Station, Texas, United States, 77843-4253
Sponsors and Collaborators
Texas A&M University
Ocera Therapeutics
Principal Investigator: Marielle Engelen, PhD Texas A&M University
  More Information

Responsible Party: Marielle PKJ Engelen, PhD, Associate Professor, Texas A&M University Identifier: NCT03159390     History of Changes
Other Study ID Numbers: 2014-0801
Study First Received: May 16, 2017
Last Updated: May 19, 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Marielle PKJ Engelen, PhD, Texas A&M University:
dietary supplements

Additional relevant MeSH terms:
Phenylacetic acid
Antimetabolites, Antineoplastic
Molecular Mechanisms of Pharmacological Action
Antineoplastic Agents processed this record on September 19, 2017