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A Study to Assess Plasma Ammonia Time-Normalized Area Under the Curve and Rate of Ureagenesis in Healthy Adult Subjects

Completed
Conditions
Ornithine Transcarbamylase Deficiency
Registration Number
NCT04269122
Lead Sponsor
Ultragenyx Pharmaceutical Inc
Brief Summary

The objective of the study is to characterize 24-hour plasma ammonia levels, characterize urea production rates in healthy normal subjects.

Detailed Description

During Part 1, eligible subjects will be asked to participate in 3 inpatient visits, each lasting up to 3 days (Day -1 to Day 2). Each visit will assess 24-hour ammonia levels in plasma and rate of urea production for 4 hours following ingestion of \[1-13C\]sodium acetate. Sodium acetate is used as a tracer to measure the rate of ureagenesis.

During Part 2, eligible subjects will be asked to participate in 1 inpatient visit, lasting up to 3 days (Day -1 to Day 2). The visit will assess 24-hour ammonia levels in plasma and rate of urea production for 4 hours following ingestion of \[1-13C\]sodium acetate. Sodium acetate is used as a tracer to measure the rate of ureagenesis.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
120
Inclusion Criteria
  • Body mass index between 18 and 30 kg/m2, inclusive.
Exclusion Criteria
  • History of liver disease as evidenced by any of the following: portal hypertension, ascites, splenomegaly, esophageal varices, hepatic encephalopathy, or a liver biopsy with evidence of stage 3 fibrosis.
  • Significant hepatic inflammation or cirrhosis as evidenced by imaging or any of the following laboratory abnormalities: alanine aminotransferase (ALT) or aspartate aminotransferase (AST) greater than the upper limit of normal (ULN), total bilirubin >1.5 × ULN, alkaline phosphatase >2.5 × ULN. NOTE: the ALT and/or AST levels may be repeated.
  • Subject has a history of gout.
  • Plasma ammonia level that is not within normal limits at Screening in the opinion of the Investigator or Sponsor.
  • Received any vaccine within 14 days prior to Screening.
  • Pregnant, lactating, or intending to become pregnant at any time during the study.
  • Blood transfusion within 8 weeks prior to Screening.diuretics, cyclophosphamide and other cytotoxic agents, tolbutamide, chlorpropamide, diazoxide, dichlorphenamide, pyrazinamide, probenecid, theophylline/aminophylline, riluzole, warfarin and other antithrombotic agents, supplements containing aluminum hydroxide, or iron supplements within 30 days of Part 1or Part 2.

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Primary Outcome Measures
NameTimeMethod
Rate of Ureagenesis Based On Presence of [1-13C] In UreaPart 1, Day 1 (Visits 1-3) and Part 2, Day 1: Predose (0hour) up to 4 hours post dose

Characterization of nitrogen flux as determined by production of urea. Sodium acetate is used as a tracer to measure the rate of ureagenesis.

Intra- and inter-subject coefficient of variation (CV) of AUC0-24 and Rate of UreagenesisPart 1 Treatment Period: 17 days; Part 2 Treatment Period: 3 days

Comparative analysis of both parameters

Plasma Ammonia Area Under the Curve (AUC0-24)Part 1, Day 1 (Visits 1-3) and Part 2, Day 1:Predose (0hour) up to 24 hours post dose

Characterization of ammonia production over 24hr

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

PPD Phase 1 Unit

🇺🇸

Austin, Texas, United States

PPD Phase 1 Unit
🇺🇸Austin, Texas, United States

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