Phenylketonuria (PKU)NCT07671859
PKU Microtablets Case Studies
A study testing PKU Microtablet protein substitute in people with Phenylketonuria (PKU), run by Nutricia UK Ltd at 1 site in United Kingdom.
Trial summary
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… Read more about this study
- Who is it for?
- Ages 4 years and older
- Conditions the study is for
- Phenylketonuria (PKU)
- What is being tested?
- PKU Microtablet protein substitute
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 1 Oct 2026to 1 Jul 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 4 years and older
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Male or female
- Over 4 years of age
- Patients diagnosed with any phenotype of PKU characterised by hyperphenylalaninaemia
- Have been compliant in taking at least one protein substitute, providing at least 20g protein equivalent, for at least 1 month prior to trial commencement
- Have a prescribed daily phenylalanine allowance for PKU
- Written or electronic informed consent from patient, and/or from parent/caregiver if applicable
- Participants who are anticipated to be able to take at least 20g protein equivalent of the case study product per day
Who cannot join
- Pregnant or lactating
- Requiring parenteral nutrition
- Major hepatic or renal dysfunction
- Participation in other studies within 1 month prior to entry of this study
- Allergy to any of the study product ingredients
- Investigator concern around willingness/ability of patient or parent/caregiver to comply with protocol requirement
- Treatment with Sapropterin dihydrochloride for less than 6 months
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United Kingdom1 site
University Hospitals Bristol and Weston NHS Foundation Trust
Bristol
About this study
Official title: Evaluating the Adherence, Tolerance, Acceptability and Safety of a New Amino Acid Based, Microtablet Protein Substitute in PKU: a Case Study Series
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.
- Conditions
- Phenylketonuria (PKU)
- Being tested
- PKU Microtablet protein substitute
- Medical subject headings
- Phenylketonurias
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PKU Microtablet protein substituteDietary supplement
PKU Microtablet intervention product
| Study group | Role | What they receive |
|---|---|---|
| PKU Microtabet intervention product | Experimental | Dietary Supplement: PKU Microtablet intervention product Receives: Dietary Supplement: PKU Microtablet protein substitute |
What is being measured
The primary outcome is the main question the study is designed to answer.
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).
Measured: Measured at baseline (day 1) and end of intervention (day 29)
Secondary outcomes (7)
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).
Measured: 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.
Measured: 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.
Measured: 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).
Measured: 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.
Measured: 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.
Measured: Day 1 (baseline) and day 29 (end of intervention)
Safety/ Adverse events
All adverse events will be recorded, throughout the case study.
Measured: Throughout the case study series (day 1 to day 29).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted26 Jun 2026
- Study start1 Oct 2026 (estimated)
- Primary completion1 Jun 2027 (estimated)
- Study completion1 Jul 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Phenylketonuria (PKU)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Nutricia UK Ltd
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Gary Hubbard, Dr, Study director, Nutricia, Inc.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07671859
- Sponsor's protocol ID
- PKUM2025
- Status last verified
- Sep 2026
- First submitted
- 17 Jun 2026
- Last updated
- 23 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 23 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluating the Adherence, Tolerance, Acceptability and Safety of a New Amino Acid Based, Microtablet Protein Substitute in PKU: a Case Study Series
- ClinicalTrials.gov ID
- NCT07671859
- Acronym / sponsor ID
- PKUM2025
- Conditions
- Phenylketonuria (PKU)
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 20 participants (estimated)
- Lead sponsor
- Nutricia UK LtdIndustry (pharma, biotech, devices)
- Study start
- 1 Oct 2026 (estimated)
- Primary completion
- 1 Jun 2027 (estimated)
- Study completion
- 1 Jul 2027 (estimated)
- First posted
- 26 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| PKU Microtabet intervention product | Experimental | Dietary Supplement: PKU Microtablet protein substituteDietary Supplement: PKU Microtablet intervention product |
Who may qualify
- Ages
- 4 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (7 listed)
- Male or female
- Over 4 years of age
- Patients diagnosed with any phenotype of PKU characterised by hyperphenylalaninaemia
- Have been compliant in taking at least one protein substitute, providing at least 20g protein equivalent, for at least 1 month prior to trial commencement
- Have a prescribed daily phenylalanine allowance for PKU
Key exclusion criteria (7 listed)
- Pregnant or lactating
- Requiring parenteral nutrition
- Major hepatic or renal dysfunction
- Participation in other studies within 1 month prior to entry of this study
- Allergy to any of the study product ingredients
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| PKU Microtablet protein substitutePKU Microtablet intervention product | Dietary supplement | PKU Microtabet intervention product |
Primary outcome
Gastro-intetsinal tolerance
Time frame: Measured at baseline (day 1) and end of intervention (day 29)
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).
7 secondary outcomes
Acceptability
Time frame: Measured at baseline (day 1) and end of intervention (day 29)
Compliance
Time frame: Measured at baseline (day 1) and end of intervention (day 29)
Blood Phe and Tyrosine
Time frame: Day 2 (baseline) and day 29 (end of intervention)
Anthropometry - Height
Time frame: Day 1 (baseline) and day 29 (end of intervention)
Anthropometry - Weight
Time frame: Day 1 (baseline) and day 29 (end of intervention)
Patient History
Time frame: Day 1 (baseline) and day 29 (end of intervention)
Safety/ Adverse events
Time frame: Throughout the case study series (day 1 to day 29).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Sep 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Gary Hubbard, Dr study director
Nutricia, Inc.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing PKU Microtablet protein substitute in people with Phenylketonuria (PKU), run by Nutricia UK Ltd at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 23 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Vicky Furmidge-Owen (+447387 521508, vicky.furmidge-owen@nutricia.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Gastro-intetsinal tolerance (time frame: Measured at baseline (day 1) and end of intervention (day 29)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Sep 2026.