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Completed

NCT Number: NCT05249218

Impact of Fruit and Vegetables in PKU

In the UK, some fruits and vegetables are permitted without measurement in the diets of people with phenylketonuria (PKU). It is proven that fruits and vegetables containing phenylalanine (Phe) up to 75mg/100g (e.g. carrots, sweet potato, tomatoes) do not affect blood Phe control but it is unknown to what extent fruits and vegetables containing Phe from 76-100mg/100g (e.g. cauliflower, broccoli, beansprouts and asparagus) increase blood Phe levels. In addition, there is very little information about how differently animal and vegetable protein affect blood Phe levels. It is believed that plant protein may have less bioavailability and therefore have less impact on blood Phe control. The investigators aim is to perform a randomized controlled study over 21 weeks in children (5-12y) with PKU. Children will be studied during five different time periods, examining the effect on blood Phe control when increasing Phe intake from vegetables/fruits containing Phe from 76-100 mg/100g vs. animal sources. At the end of the study, fruits and vegetables containing 76- 100mg Phe/100g will continue to be given as "exchange-free" for 6 months. This is a practical, cost effective study and should bring benefit to all people with PKU following a very restrictive diet both within the UK and throughout the world.

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Key information

Conditions

Phenylketonurias Amino Acid Metabolism, Inborn Errors Brain Diseases Brain Diseases, Metabolic Brain Diseases, Metabolic, Inborn Central Nervous System Diseases Congenital, Hereditary, and Neonatal Diseases and Abnormalities Genetic Diseases, Inborn Metabolic Diseases Metabolism, Inborn Errors Nervous System Diseases Nutritional and Metabolic Diseases

Age range

5 year–12 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Birmingham Women's and Children's Hospital

Birmingham, West Midlands, B4 6NH, United Kingdom

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • PKU patients diagnosed by NBS and BH4 deficiencies;
  • Early and continuously treated;
  • Adherent to their prescribed PKU diet consisting of a protein-restricted diet and Phe-free amino acid based protein substitute;
  • In good general health as evidenced by medical history;
  • Able to provide written informed consent/assent (parent/child);
  • Able to comply with the study protocol and take study product according to the opinion of the PI;
  • Patients with good metabolic control (age 5-12y, 120-360μmol/L) with 3 out of 4 levels within range prior to consent (if 2 of 4 above target range but one close to the upper limit, PI to decide if patient can enter the study).

Exclusion criteria

  • Concomitant diseases / disorders such as renal or gut disease / disorders and diabetes;
  • Dislikes fruits and vegetables containing 76-100 mg of Phe/100g e.g.brocolli or cauliflower;
  • Treated with BH4 (sapropterin);
  • Presence of intercurrent infection;
  • Patients with poor metabolic control (age 5-12y, >360μmol/L).

Treatment and study plan

Phase B - Extra 1 Phe exchange from fruits/vegetables containing Phe from 76-100mg/100g

Other

Usual low Phe diet + 60g fruits/vegetables containing Phe from 76-100mg/100g

Phase C - Extra 2 Phe exchanges from fruits/vegetables containing Phe from 76-100mg/100g

Other

Usual low Phe diet + 120g fruits/vegetables containing Phe from 76-100mg/100g

Phase D - Extra 1 Phe exchange from milk or yoghurt

Other

Usual low Phe diet but 1 x 50 mg extra Phe exchange from milk or yoghurt

Phase E - Extra 2 Phe exchanges from milk or yoghurt

Other

Usual low Phe diet but 2 x 50 mg extra Phe exchange from milk or yoghurt eaten daily

Primary outcomes

  1. Blood Phe levels three times a week of patients with PKU taking extra 1 or 2 exchanges of fruits and vegetables containing 76-100mg of Phe/100g during 4 weeks each.

    Time frame: 8 weeks

  2. Blood Phe levels three times a week of patients with PKU taking extra 1 or 2 exchanges of animal protein during 4 weeks each.

    Time frame: 8 weeks

Secondary outcomes

  1. Blood Phe levels three times a week with PKU taking fruits and vegetables containing 76-100mg of Phe/100g without measurement during 6 months.

    Time frame: 6 months

Sponsors and collaborators

Lead sponsor

Alex Pinto

Other

Registry information

Official study title

Impact of Fruits and Vegetables on Metabolic Control in Children With PKU

Important dates

Study start
2019
Primary completion
2021
Study completion
2021
First posted
Feb 21, 2022
Registry last updated
Feb 21, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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