An interventional study of PKU Microtablet protein substitute in Phenylketonuria (PKU), sponsored by Nutricia UK Ltd. Not yet recruiting at 1 site in United Kingdom. Open to participants aged 4 Years and older. Per ClinicalTrials.gov, last updated 2026-09-23.
Sponsored by Nutricia UK Ltd (part of Danone) · Not applicable, Interventional, and Basic science
Phenylalanine (Phe) free protein substitutes are typically presented in ready to drink liquid or powder format and are made up with water to a set volume. Despite recent advancements related to the taste, scent and texture of commercially available protein substitutes, a proportion of PKU patients choose to consume tablet-based protein substitutes. Protein substitutes in tablet format may help overcome taste, scent and texture concerns associated with powdered and liquid preparations. Indeed, previous research has shown that protein substitute tablets are an effective strategy to manage PKU in children, teenagers and adults. Nonetheless, the daily burden and discipline required often impedes compliance, especially alongside the restrictive low-protein diet. Achieving compliance with multivitamin supplements when given alongside protein substitutes therefore becomes especially challenging. This is particularly true for adolescent, adult and maternal populations.
PKU Microtablets have recently been developed. PKU Microtablets are a new phenylalanine-free tablet protein substitute combined with vitamins, minerals and trace elements. As patient acceptability is fundamental to the successful use of any protein substitute, investigation is needed to assess the compliance, tolerance and acceptability of PKU Microtablets as part of a low phenylalanine dietary regimen in PKU patients.
This series of case-studies aims to evaluate the gastrointestinal tolerance, acceptability, compliance, and safety of this protein substitute in both adults and children from 4 years. These case studies will last 29 days in total, including a 1-day baseline period followed by a 28-day intervention period. The case studies will be conducted across multiple specialist metabolic centres in the UK.
191 studies on the registry are indexed under Phenylketonurias; 40 are open to participants now.
This study's planned enrollment of 20 is below the median of 27 across 122 interventional studies indexed under Phenylketonurias.
Browse Phenylketonurias studies →Nutricia UK Ltd is the lead sponsor of 28 studies on the registry; 5 are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Dietary Supplement: PKU Microtablet intervention product
Dietary Supplement: PKU Microtablet protein substitute
PKU Microtablet intervention product
Gastro-intetsinal tolerance
GI tolerance will be recorded by the Dietitian at baseline on Day 1 and at the end of the case study period (Day 29). GI tolerance will be recorded using a standardised questionnaire to capture perceived severity (none, mild, moderate or severe) of common gastrointestinal symptoms (diarrhoea, constipation, bloating, abdominal discomfort, vomiting and nausea).
Time frame: Measured at baseline (day 1) and end of intervention (day 29)
Acceptability
Acceptability (ease of use and liking) of the patients' usual protein substitute and the study product will be assessed by the Dietitian at baseline (Day 1) and the end of the case study period (Day 29) by a series of questions posed to the patient and/or parent/caregiver. Acceptability questions will assess the patient's sensory experience, ease of use, tolerance, and overall self-rated acceptability on a 5-point Likert scale from Terrible (worst) to Great (best).
Time frame: Measured at baseline (day 1) and end of intervention (day 29)
Compliance
Compliance with the recommended intake of the patients' usual protein substitute (during baseline) and with the study product (during the case study period) will be assessed by the Dietitian at baseline (Day 1) and at the end of the case study (Day 29). Patients and/or parents/caregivers will be asked to recall the amount of their protein substitute taken in the past 24 hours and on average. This will be compared to the amount recommended to be consumed by their Dietitian. The daily amount prescribed by the Dietitian managing the patient's care will be recorded at the start of the case study and any changes to this prescription during the case study will also be noted.
Time frame: Measured at baseline (day 1) and end of intervention (day 29)
Blood Phe and Tyrosine
Participants will be required to provide a total of two fasting fingerprick blood samples as dried blood spots; one on the first day of the intervention period (Day 2) before consuming any of the case study product, and one at the end of the intervention period (Day 29). These tests will be conducted in addition to any usual blood tests the participants conduct as part of their usual disease management, which vary in frequency with the age of the participant and the local policy. Dietitians will also be asked to describe the patient's metabolic control during the case study period.
Time frame: Day 2 (baseline) and day 29 (end of intervention)
Anthropometry - Height
Height will be measured, using standard methods, recorded to the nearest 0.1cm (at baseline only) and used to calculate body mass index (BMI, kg/m2).
Time frame: Day 1 (baseline) and day 29 (end of intervention)
Anthropometry - Weight
For safety purposes, at baseline (Day 1) and at the end of the case study (Day 29), body weight (kg) will be measured where possible using standard methods, recorded to the nearest 0.1kg using a weighing scale without heavy clothing.
Time frame: Day 1 (baseline) and day 29 (end of intervention)
Patient History
A detailed patient history will be recorded at baseline to assess previous compliance to protein substitutes, relevant medical and clinical issues, medication(s) prescribed, and any other relevant information related to the patient's condition or dietary management.
Time frame: Day 1 (baseline) and day 29 (end of intervention)
Safety/ Adverse events
All adverse events will be recorded, throughout the case study.
Time frame: Throughout the case study series (day 1 to day 29).
Plan to share: No
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This study is not yet recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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