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Completed

NCT Number: NCT05577065

A Study to Assess the Effect of a Probiotic on Upper Respiratory Tract Infections in Healthy Children

This study evaluates the efficacy of a single strain probiotic on the incidence, duration and severity of upper respiratory tract infections in healthy, school-age children.

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Key information

Age range

2 year–8 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Atlantia Food Clinical Trials

Cork, T23 R50R, Ireland

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Have a parent/guardian able to give written informed consent.
  • If ≥7 years, be able to give written informed assent.
  • Healthy children aged 2 - 8 years old.
  • In general good health, as determined by the investigator.
  • Attending a registered childcare provider or school.
  • Willing to consume the study product daily for the duration of the study.

Exclusion criteria

  • Has URTI symptoms at the time of randomisation.
  • Are <2 or ≥9 years old.
  • Diagnosed with concomitant chronic infections, chronic systemic diseases, autoimmune diseases (e.g. asthma - generally only formally diagnosed after child is 6 years), immunodeficiency, metabolic diseases, chronic respiratory tract diseases including respiratory allergies and cystic fibrosis or congenital cardiac defects.
  • Has a family household member that smokes cigarettes in the home.
  • Has taken antibiotics within the previous 2 weeks prior to randomisation.
  • Has taken probiotic supplements within the previous 2 weeks prior to randomisation
  • Daily intake of immune stimulating products, including but not limited to echinacea, vitamin C and zinc in the 2 weeks before randomisation (multivitamins allowed).
  • Has any significant health conditions that would prevent them from fulfilling the study requirements, put the Participant at risk or would confound the interpretation of the study results as judged by the investigator on the basis of medical history and routine laboratory test results.
  • Taking a medication that the investigator believes would interfere with the objectives of the study or pose a safety risk or confound the interpretation of the study results.
  • Has an active gastrointestinal disorder or previous gastrointestinal surgery (appendicectomy allowed).
  • Has a gastrointestinal or chronic infective disease (i.e., coeliac disease, diarrhoea, Crohn's disease, ulcerative colitis, irritable bowel syndrome, diverticulosis, stomach or duodenal ulcers, hepatitis, HIV, cancer, etc.), or with a history of such diseases.
  • Planned extensive travel (for >1 month) during the study duration.
  • Parent/guardian who, in the opinion of the investigator, are considered to be poor attendees or unlikely for any reason to be able to comply with the study.
  • Participants may not be receiving treatment involving experimental drugs. If the Participant has been in a recent experimental trial/study, these must have been completed not less than 60 days prior to this study.
  • Any Participant who is the child of an employee of the study site or an Atlantia Clinical Trials employee or their close family member or a member of their household.

Treatment and study plan

Probiotic

Dietary Supplement

Single strain probiotic in the form of a sachet with a daily dose of 3E+9 Colony Forming Unit (CFU) per day for 26 weeks.

Placebo

Dietary Supplement

Matching placebo in the form of a sachet once daily for 26 weeks

Primary outcomes

  1. Effect of 26 week consumption of probiotic on the total number of days that, otherwise healthy, children suffer from upper respiratory tract infection (URTI)

    Time frame: Entire follow up period (total of 180 days)

    Presence of an URTI defined by a score of >2 on the Jackson Cold Scale (maximum score 3) where a lower score means better outcomes compared to baseline

Secondary outcomes

  1. Effect of 26 week consumption of probiotic on the number of children reporting at least one URTI

    Time frame: Day 0, Day 90, Day 180

    The presence of an URTI defined by a score of >2 on the Jackson Cold Scale (maximum score 3) where a lower score means better outcomes compared to baseline

  2. Effect of 26 week consumption of probiotic on the average duration of URTIs reported by participants

    Time frame: Day 0, Day 90, Day 180

    Duration of URTI measured through the WURSS-K questionnaire (Maximum score 42) where a lower score means better outcomes compared to baseline

  3. Effect of 26 week consumption of probiotic on the severity of URTI-related symptoms reported by participants

    Time frame: Day 0, Day 90, Day 180

    Severity of URTI measured through the WURSS-K questionnaire (Maximum score 42) where a lower score means better outcomes compared to baseline

  4. Effect of 26 week consumption of probiotic on the total number of reported missed days of school/childcare due to illness

    Time frame: Day 0, Day 90, Day 180

    Recorded through the WURSS-K questionnaire (Maximum score 42) where a lower score means better outcomes compared to baseline

  5. Effect of 26 week consumption of probiotic on the reported incidence of antibiotic use

    Time frame: Day 0, Day 90, Day 180

    Recorded through the WURSS-K questionnaire (Maximum score 42) where a lower score means better outcomes compared to baseline

  6. Effect of 26 week consumption of probiotic on Salivary Immunoglobulin A levels (IgA) (mg/dL)

    Time frame: Day 0, Day 180

    Measured via saliva sample

  7. Effect of 26 week consumption of probiotic on the incidence of gastrointestinal infections

    Time frame: Day 0, Day 90, Day 180

    Recorded through the WURSS-K questionnaire (Maximum score 42) where a lower score means better outcomes compared to baseline

Other outcomes

  1. Faecal Microbiome analysis

    Time frame: Day 0, Day 180

    Shallow shotgun metagenomic sequencing for 20% of cohort

Sponsors and collaborators

Lead sponsor

The Archer-Daniels-Midland Company

Industry

Collaborators

  • Atlantia Food Clinical Trials

Registry information

Official study title

A Randomised, Double-blinded, Placebo-controlled, Parallel Study, to Assess the Effect of a Probiotic on the Incidence, Duration and Severity of Upper Respiratory Tract Infections in Healthy Children

Acronym: KLEENEX

Important dates

Study start
2023
Primary completion
2024
Study completion
2024
First posted
Oct 13, 2022
Registry last updated
Apr 9, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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