Phe for Me? The Effects of L-Phe on PKU Carriers and Non-carriers

NCT ID: NCT06119048

Last Updated: 2025-05-15

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 50 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-06-18
• Study Completion Date: 2025-12-31

Brief Summary

This is a clinical intervention study of PKU carriers (cases) and non-carriers (controls). Upon completing the informed consent process, participants will complete baseline measures of chronic mental health prior to the intervention (PHQ-9, GAD-7, BIS-11). Participants will attend the Human Nutraceutical Research Unit (HNRU) at the University of Guelph, fasted, and first undergo baseline measures of cognition and acute mental health (mood) and provide samples or saliva, urine and dried blood spots to evaluate phenylalanine (Phe), tyrosine (Tyr) and their metabolites (PAH pathway functioning) as well as for genetic testing of the PAH gene. Participants will also complete a brief questionnaire which will include age, sex, ethnicity, income, weight and height (measured using a stadiometer and calibrated weigh scale), and confirmation that participants arrived to the lab fasted (i.e. have only had water to drink and no other foods/ beverages prior to analyses). Blood pressure and heart rate will also be measured at baseline.

Following baseline tests, participants will consume a pure L-Phe supplement dosed at 100 mg/kg mixed with 125 mL of water and 125mL of orange juice. Blood pressure and heart rate will be repeated at 1-hour post-L-Phe consumption. Two-hours postprandial, participants will repeat the cognitive tests and acute mental health (mood) assessment, blood pressure and heart rate measurement and provide follow-up saliva, urine and dried blood spot samples. Participants will also be asked to report any side effects they experienced with the L-Phe consumption.

Conditions

Autosomal Recessive Disorder (Genetic Carriers of PKU)

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Genetic Carriers and Non-Carriers of PKU

Group Type: EXPERIMENTAL

L-Phenylalanine

Intervention Type: DIETARY_SUPPLEMENT

100 mg/kg

Interventions

L-Phenylalanine

100 mg/kg

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• Carrier or non-carrier of PKU
• At least 18 Years of age
• Comfortable fasting the morning of the study (no food or drink other than water)

Exclusion Criteria

• Diagnosed with: PKU, severe neurodegenerative conditions affecting cognition (e.g. Alzheimer's, Parkinson's, dementia), melanoma, hypertension, liver disease and/or kidney disease
• Diagnosed with hypertension or hypotension
• Taking a monoamine oxidase inhibitor anti-depressant
• Pregnant or breastfeeding
• Orange/citrus allergy or intolerance
• Body weight 150 kg or greater
• History of fainting during blood sampling

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

McMaster University

OTHER

Sponsor Role: collaborator

Laval University

OTHER

Sponsor Role: collaborator

University of Guelph

OTHER

Sponsor Role: lead

Responsible Party

Justine Keathley

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

University of Guelph

Guelph, Ontario, Canada

Site Status: NOT_YET_RECRUITING

University of Guelph

Guelph, Ontario, Canada

Site Status: RECRUITING

Countries

Canada

Central Contacts

Justine R Keathley, PhD

Role: CONTACT

jkeathle@uoguelph.ca

5198244120

Facility Contacts

Justine R Keathley, PhD

Role: primary

jkeathle@uoguelph.ca

Justine Keathley

Role: primary

519-824-4120

Other Identifiers

23-03-017

Identifier Type: -

Identifier Source: org_study_id