PKU Microtablets case studies
Research type
Research Study
Full title
Evaluating the adherence, tolerance, acceptability and safety of a new amino acid based, micro tablet protein substitute in PKU: a case study series
IRAS ID
362315
Contact name
Gary Hubbard
Contact email
Sponsor organisation
Nutricia
ISRCTN Number
ISRCTN00000000
Clinicaltrials.gov Identifier
Duration of Study in the UK
1 years, 6 months, 1 days
Research summary
Phenylketonuria (PKU) is an inherited disorder of amino acid metabolism which requires lifelong management to avoidcognitive impairment and disability. The dietary management of PKU is complex and burdensome for patients and their families. It involves the restriction of dietary protein intake, supplementation with phenylalanine-free protein substitutes, and can include consumption of low-protein food products, to ensure optimal metabolic control, whilst meeting nutrient requirements for growth and normal functioning.
Due to the strict nature of the diet (e.g., no meat, fish, dairy products, wheat flour or bread) nutritional deficiencies may occur, such as vitamins (e.g., B12), minerals (calcium, selenium, zinc). This highlights the importance of fortified protein substitutes (PS) not only for meeting protein needs, but also as a major supply of other critical nutrients.
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.
Nutricia Ltd has developed PKU Microtablets, 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
REC name
Wales REC 4
REC reference
25/WA/0338
Date of REC Opinion
12 Nov 2025
REC opinion
Favourable Opinion