NCT07671859

Brief 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 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.

Trial Health

63
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
20

participants targeted

Target at below P25 for not_applicable

Timeline
11mo left

Started Jul 2026

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress9%
Jul 2026Jul 2027

First Submitted

Initial submission to the registry

June 17, 2026

Completed
9 days until next milestone

First Posted

Study publicly available on registry

June 26, 2026

Completed
5 days until next milestone

Study Start

First participant enrolled

July 1, 2026

Completed
11 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 1, 2027

Expected
1 month until next milestone

Study Completion

Last participant's last visit for all outcomes

July 1, 2027

Last Updated

June 26, 2026

Status Verified

June 1, 2026

Enrollment Period

11 months

First QC Date

June 17, 2026

Last Update Submit

June 23, 2026

Conditions

Outcome Measures

Primary Outcomes (1)

  • 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 at baseline (day 1) and end of intervention (day 29)

Secondary Outcomes (7)

  • Acceptability

    Measured at baseline (day 1) and end of intervention (day 29)

  • Compliance

    Measured at baseline (day 1) and end of intervention (day 29)

  • Blood Phe and Tyrosine

    Day 2 (baseline) and day 29 (end of intervention)

  • Anthropometry - Height

    Day 1 (baseline) and day 29 (end of intervention)

  • Anthropometry - Weight

    Day 1 (baseline) and day 29 (end of intervention)

  • +2 more secondary outcomes

Study Arms (1)

PKU Microtabet intervention product

EXPERIMENTAL

Dietary Supplement: PKU Microtablet intervention product

Dietary Supplement: PKU Microtablet protein substitute

Interventions

PKU Microtablet intervention product

PKU Microtabet intervention product

Eligibility Criteria

Age4 Years+
Sexall
Healthy VolunteersNo
Age GroupsChild (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

  • 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

You may not qualify if:

  • 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

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University Hospitals Bristol and Weston NHS Foundation Trust

Bristol, United Kingdom

Location

MeSH Terms

Conditions

Phenylketonurias

Condition Hierarchy (Ancestors)

Brain Diseases, Metabolic, InbornBrain Diseases, MetabolicBrain DiseasesCentral Nervous System DiseasesNervous System DiseasesAmino Acid Metabolism, Inborn ErrorsMetabolism, Inborn ErrorsGenetic Diseases, InbornCongenital, Hereditary, and Neonatal Diseases and AbnormalitiesMetabolic DiseasesNutritional and Metabolic Diseases

Study Officials

  • Gary Hubbard, Dr

    Nutricia, Inc.

    STUDY DIRECTOR

Central Study Contacts

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
SINGLE GROUP
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

June 17, 2026

First Posted

June 26, 2026

Study Start

July 1, 2026

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

July 1, 2027

Last Updated

June 26, 2026

Record last verified: 2026-06

Data Sharing

IPD Sharing
Will not share

Locations