PKU Protein Requirements

Emory University

Status: Begins enrollment this month

Conditions: PKU

Treatments: Other: Nonradioactive stable oral isotope; Other: Test diet

Study type: Interventional

Funder types: Other

Identifiers

NCT07194993

STUDY00009869

Details and patient eligibility

About

The objective of this research is to determine the protein requirements based on genotype and medical food consumption in a sample of adults with Phenylketonuria (PKU) using the indicator amino acid oxidation (IAAO) method.

Full description

Current phenylketonuria (PKU) protein guidelines are based on outdated methods and do not account for differences in genetics or how much medical formula an individual consumes. This research aims to determine more accurate and personalized protein requirements in adults with PKU that have different genetic changes using a safe and direct method called the indicator amino acid oxidation technique. The study will address two specific aims: Aim 1 will determine the protein requirements of adults with PKU that have different genetic changes and Aim 2 will investigate how the ratio of medical formula to protein intake from natural foods affects protein needs.

Adults with PKU will be recruited for this study, and vulnerable populations will not be included.

This study includes surveys, anthropometric measurements, body composition analysis, indirect calorimetry, diet history, collection of blood, urine, and expired breath samples, administration of study day diets and an oral stable isotope protocol.

Recruitment will be at Emory Genetics Clinic. Informed consent will be obtained with an in-person signature or by an electronic IRB approved signature. Participants will attend one preliminary visit and 7 study days. Each study day will last 8 hours. Participants will be enrolled for approximately 4-6 months.

Participants will have the option to bank plasma and urine samples for future use.

Enrollment: 12 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• will be males and females (50:50) 18 years and older who were diagnosed with PKU through newborn screening or diagnosis later in life, capable of providing consent, and have previously had mutation testing

Exclusion criteria

• include concurrent illness, recent history of weight loss or acute illness during the past 6 months that could affect protein metabolism, pregnancy, lack of regular menstruation, implantable electronic devices or pacemakers, history of claustrophobia, and inability to provide consent. In addition, participants will be excluded if their genotype subgroup has already reached its predefined maximum enrollment (n=4)

Trial design

Primary purpose: Other

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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12 participants in 1 patient group

Adults with PKU receiving test diet and Oral stable nonradioactive isotope provision

Experimental group

Description:

Participants will receive amino acid tracer (Oral stable nonradioactive isotope provision) and test diet (medical food) throughout each study day, for a total of 7 study days.

Treatment:

Other: Test diet

Other: Nonradioactive stable oral isotope