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Metabolism of Ornithine Phenylacetate

Human Metabolism of Ornithine Phenylacetate: A Study in Healthy Volunteers

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03159390
Acronym
OCERA OP
Enrollment
20
Registered
2017-05-18
Start date
2015-02-03
Completion date
2015-04-30
Last updated
2025-09-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy

Keywords

dietary supplements

Brief summary

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.

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.

Interventions

OTHERphenylacetate salt of ornithine

Sponsors

Ocera Therapeutics
CollaboratorINDUSTRY
Texas A&M University
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
40 Years to 70 Years
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

Design outcomes

Primary

MeasureTime frameDescription
metabolism of ornithine phenylacetate to glutamate and glutamine4 study days that are 8 hours eachThe 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.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 20, 2026