NCT03939052

Brief Summary

Phenylketonuria (PKU) is an inherited inborn error of phenylalanine (PHE) metabolism caused by decreased activity of phenylalanine hydroxylase (PAH) enzyme. Therefore, PHE accumulates in plasma leading to mental problems. Treatment is a phenylalanine-restricted diet with sufficient protein. However, the optimum protein requirements are still unknown and compliance with diet is not satisfactory in PKU adults. A Previously established technique called indicator amino acid oxidation (IAAO) will be used to determine protein requirements from amino acid based formula vs. glycomacropeptide (GMP) in adults with PKU (≥ 19y). This study will help treat adults with enough protein ensuring maintenance of health.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
6

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Jul 2019

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

May 1, 2019

Completed
5 days until next milestone

First Posted

Study publicly available on registry

May 6, 2019

Completed
2 months until next milestone

Study Start

First participant enrolled

July 19, 2019

Completed
2.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 1, 2021

Completed
1.1 years until next milestone

Study Completion

Last participant's last visit for all outcomes

January 13, 2023

Completed
Last Updated

July 25, 2024

Status Verified

July 1, 2024

Enrollment Period

2.4 years

First QC Date

May 1, 2019

Last Update Submit

July 24, 2024

Conditions

Phenylketonuria

Keywords

PhenylketonuriaPKUPhenylalanine metabolismProtein requirementsIndicator Amino acid OxidationStable isotopesGMPGlycomacropeptide

Outcome Measures

Primary Outcomes (2)

  • 13 Co2 production

    Breath samples will be collected during the study to measure the rate of oxidation of tracer in the expired breath.

    8 hours (1 study day). 3 samples will collected as a baseline prior to isotope protocol and 6 samples after 2 hours and 30 minutes of starting the tracer protocol. Data will be reported an average of 2 years.

  • Lysine flux

    Urine samples will be collected during the study to measure the flux enrichment in urine.

    8 hours (1 study day). 1 sample will collected as a baseline prior to isotope protocol and 2 samples after 2 hours and 30 minutes of starting the tracer protocol. Data will be reported an average of 2 years.

Secondary Outcomes (3)

  • Phenylalanine concentrations

    One sample (at 6th meal) after starting of the tracer protocol. Data will be reported an average of 2 years.

  • Tyrosine concentrations

    One sample (at 6th meal) after starting of the tracer protocol. Data will be reported an average of 2 years.

  • 16 other amino acids

    One sample (at 6th meal) after starting of the tracer protocol. Data will be reported an average of 2 years.

Study Arms (1)

Protein intake

EXPERIMENTAL

Free amino acids vs. Glycomacropeptide (GMP)

Dietary Supplement: Free amino acids intake

Interventions

Free amino acids intakeDIETARY_SUPPLEMENT

Oral consumption of eight hourly experimental meals- -4 tracer free experimental meals containing a mixture of free amino acids and calories from protein free flavoured liquid, protein free cookies and corn oil -4 isotopically labeled experimental meals. The same protocol will be repeated with glycomacropeptide (GMP).

Also known as: glycomacropeptide (GMP) intake
Protein intake

Eligibility Criteria

Age19 Years - 50 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Adults more than 19 years of age who are diagnosed with PKU and clinically stable with no acute illness

You may not qualify if:

  • Adults with PKU under age 19 year
  • Adults diagnosed with PKU but are currently ill with a fever or cold

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

BC Children's Hospital Research Institute, University of British Columbia

Vancouver, British Columbia, V5Z4H4, Canada

Location

MeSH Terms

Conditions

Phenylketonurias

Interventions

caseinomacropeptide

Condition Hierarchy (Ancestors)

Brain Diseases, Metabolic, InbornBrain Diseases, MetabolicBrain DiseasesCentral Nervous System DiseasesNervous System DiseasesAmino Acid Metabolism, Inborn ErrorsMetabolism, Inborn ErrorsGenetic Diseases, InbornCongenital, Hereditary, and Neonatal Diseases and AbnormalitiesMetabolic DiseasesNutritional and Metabolic Diseases

Study Officials

  • Rajavel Elango, PhD

    BC Children's Hospital Research Institute, University of British Columbia

    PRINCIPAL INVESTIGATOR

  • Sandra Sirrs, MD

    University of British Columbia

    STUDY CHAIR

  • Sylvia Stockler, MD

    University of British Columbia

    STUDY CHAIR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
SUPPORTIVE CARE
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Associate Professor

Study Record Dates

First Submitted

May 1, 2019

First Posted

May 6, 2019

Study Start

July 19, 2019

Primary Completion

December 1, 2021

Study Completion

January 13, 2023

Last Updated

July 25, 2024

Record last verified: 2024-07

Locations

CA(1)