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SNAP: Study Nutrients in Adult PKU (SNAP)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03858101
Recruitment Status : Recruiting
First Posted : February 28, 2019
Last Update Posted : September 24, 2019
Information provided by (Responsible Party):
Nutricia Research

Brief Summary:
Phenylketonuria (PKU) is a rare inherited metabolic disorder, where subjects are born with a genetic deficiency in the phenylalanine hydroxylase enzyme (PAH), which leaves them unable to convert Phenylalanine (Phe) into Tyrosine (Tyr). PKU patients have specific dietary needs and must follow a restrictive diet in the aim of preventing toxic levels of the amino acid phenylalanine (Phe) accumulation.

Condition or disease

Detailed Description:
The aim of this explorative cross-sectional study is to gain quantitative insights on blood nutrient levels of adult PKU patients on a protein substitute.

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Study Type : Observational
Estimated Enrollment : 80 participants
Observational Model: Other
Time Perspective: Cross-Sectional
Official Title: An Exploratory Matched Case-control Study to Measure Blood Nutrient Levels of Adult PKU Patients on a Protein Substitute.
Actual Study Start Date : April 15, 2019
Estimated Primary Completion Date : September 1, 2020
Estimated Study Completion Date : December 31, 2020

PKU subjects
Age and sex-matched non-PKU comparison subjects

Primary Outcome Measures :
  1. Blood nutritional status [ Time Frame: day 1 ]
    Micro-and macronutrients and amino acid levels [in a.o. mg/L]

Secondary Outcome Measures :
  1. Blood nutritional status [ Time Frame: day 1 ]
    Phe/Tyr ratio [µmol/L]

  2. Nutrient intake [ Time Frame: day 1 - day 7 ]
    measured by three-day food diary. Nutrients in [mg/day]

  3. Subjective cognitive well-being [ Time Frame: day 1 - day 7 ]
    measured by FACT-Cog questionnaire: [four domains [score-range): 1) patients' perceived cognitive impairments [0-80]; 2) perceived cognitive abilities [0-36]; 3) noticeability or comments from others [0-16]; 4) impact of cognitive changes on quality of life [0-16]. A summary score is obtained by summing all item scores [0-148].

Biospecimen Retention:   Samples Without DNA
Blood samples

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
PKU subjects (18 years and olders) and non PKU comparisons. Belgium, Poland, The Netherlands

- Inclusion Criteria:

Both PKU and Non-PKU comparison subjects:

  1. Age ≥18 years
  2. Willing and able to provide signed informed consent PKU specific inclusion criteria
  3. PKU patients identified by newborn screening and started low Phe diet before 1 month age
  4. Usage of at least one Phe-free protein substitute (i.e. an amino acid mixture including micronutrients) on a daily basis for at least 26 consecutive weeks up to Visit 1

    Non-PKU comparison subjects specific inclusion criteria:

  5. Same age- (±3 years) and sex as an included PKU subject

    • Exclusion Criteria:

Both PKU and Non-PKU comparison subjects:

  1. For women: Currently pregnant or lactating
  2. Current psychiatric disorders
  3. Current Substance Use Disorders (as described in DSM V)
  4. Current use of psychotropic and/or inotropic medication
  5. Omega-3, antioxidant, (multi)vitamin and/or (multi)mineral supplement use within six weeks prior to entry in the study
  6. Severe hepatic, thyroid or renal dysfunction
  7. No acute illnesses like flu, diarrhea, or vomiting (subjects should be symptom free for a week prior to V1)
  8. Participation in any other clinical intervention studies involving test products concomitantly or within six weeks prior to entry into the study
  9. Other family members taking part in this study

    PKU subject specific exclusion criteria:

  10. Use of BH4, or drugs that may interfere with main outcomes

    Non-PKU comparison subjects specific exclusion criteria:

  11. Any condition or special diet (e.g. vegan or vegetarian diet) that effects the metabolism and/or normal dietary pattern/intake
  12. A first or second degree relative with inborn errors of metabolism
  13. Living together with someone with inborn errors of metabolism (e.g. partner, spouse or roommate)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03858101

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Contact: Nutricia Research +31 30 295000

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UZ Gent Recruiting
Gent, Belgium
Sponsors and Collaborators
Nutricia Research
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Responsible Party: Nutricia Research Identifier: NCT03858101    
Other Study ID Numbers: MBB16TA10778
First Posted: February 28, 2019    Key Record Dates
Last Update Posted: September 24, 2019
Last Verified: September 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Additional relevant MeSH terms:
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Brain Diseases, Metabolic, Inborn
Brain Diseases, Metabolic
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Amino Acid Metabolism, Inborn Errors
Metabolism, Inborn Errors
Genetic Diseases, Inborn
Metabolic Diseases