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Upper Respiratory Tract InfectionNCT07154992

Clinical Trial to Evaluate the Efficacy of Lacticaseibacillus Rhamnosus CRL1505 in the Prevention of Upper Respiratory Tract Infections in Children

A study testing Probiotic - Lacticaseibacillus rhamnosus CRL1505 in people with Upper Respiratory Tract Infection and Prevention, run by Bioithas SL at 1 site in Spain.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
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Trial summary

Randomized, double-blind, placebo-controlled, parallel-group, clinical trial to assess the efficacy of the intake of a probiotic product composed of Lacticaseibacillus rhamnosus CRL1505 strain in reducing or preventing upper respiratory tract infections (URTIs) in a healthy paediatric population. Read more about this study

Who is it for?
Ages 3 to 12 yearsHealthy volunteers can take part
Conditions the study is for
Upper Respiratory Tract Infection, Prevention
What is being tested?
Probiotic - Lacticaseibacillus rhamnosus CRL1505
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
268 participants
Where
1 siteSpain
Study dates
17 Dec 2024to Apr 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 3 to 12 years
  • All sexes
  • Healthy volunteers accepted
  • Child

Who may be able to join

  • Healthy children aged 3 to 12 years.
  • Signed Informed Consent by the parents

Who cannot join

  • Chronic pathological conditions, such as chronic respiratory diseases (asthma, chronic bronchitis, etc.), chronic heart diseases, chronic neurological diseases (psychomotor impairment, etc.), chronic liver diseases, chronic kidney diseases, chronic gastrointestinal diseases, hematological disorders, etc., or any other disease or condition that the investigator considers to significantly affect the health of the participating child.
  • Metabolic disorders, such as diabetes mellitus, obesity, etc.
  • Immunodeficiency, including HIV infection, chronic corticosteroid treatment, etc.
  • Nasal polyps, nasal ulcers, or other conditions that may cause nasal obstruction.
  • Regular use of medications or dietary supplements that may influence the study outcomes (immunosuppressants/immunostimulants, including echinacea supplements, analgesics, anti-inflammatory drugs, antitussives/expectorants, flu preparations, decongestants, antibiotics, antihistamines, probiotics, etc.) within the 4 weeks prior to the start of the clinical trial.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Juan Gabriel Agüera Santos contact

+34623022586

juan.aguera@bioithas.com

Spain1 site, 1 recruiting
  • MiBioPath Research Group (UCAM)

    Murcia

    Vicente Navarro López, +34865780170, vicente.navarro@bioithas.com

    Recruiting

Other trials in Spain

About this study

Official title: Randomized, Double-blind, Placebo-controlled Clinical Trial to Evaluate the Efficacy and Safety of Lacticaseibacillus Rhamnosus CRL1505 in the Prevention of Upper Respiratory Tract Infections in a Healthy Paediatric Population

Randomized, double-blind, placebo-controlled, parallel-group, clinical trial to assess the efficacy of the intake of a probiotic product composed of Lacticaseibacillus rhamnosus CRL1505 strain in reducing or preventing upper respiratory tract infections (URTIs) in a healthy paediatric population.

Read the detailed description

Randomized, double-blind, placebo-controlled, parallel-group, clinical trial.

The study aims to demonstrate the efficacy of the intake of a probiotic product composed of Lacticaseibacillus rhamnosus CRL1505 strain in reducing or preventing upper respiratory tract infections in a healthy paediatric population.

The clinical trial has an intervention period of 12 weeks and a post-treatment follow-up period of 4 additional weeks (16 weeks in total).

The study aims to demonstrate the efficacy and safety of consuming the probiotic strain Lacticaseibacillus rhamnosus CRL1505 in the prevention and reduction of the severity and duration of URTI (upper respiratory tract infections) episodes in a healthy paediatric population.

A total of 268 participants aged 3 to 12 years will be recruited and randomized into two treatment groups in a 1:1 ratio (134 participants in the PROBIOTIC GROUP and 134 participants in the PLACEBO GROUP). The two intervention groups will differ based on the treatment received: probiotic or placebo, both of which will have a similar appearance.

The study will focus on a healthy paediatric population; therefore, the exclusion criteria will eliminate children with significant acute or chronic diseases and those with an immunocompromised condition. Additionally, children receiving continuous pharmacological treatment or those who have consumed dietary supplements that could influence the study results within the four weeks prior to inclusion will be excluded. However, if these children can discontinue such treatments, they may participate in the clinical trial after a washout period. Continuous regular medication that is deemed not to influence the study outcomes regarding the efficacy of the investigational product will be allowed.

Participants will be required not to modify their diet or physical activity during the course of the study.

The inclusion process will take place during winter months, to ensure that the study coincides with the months of highest URTI incidence.

Since this clinical trial will be conducted in minors, continuous evaluation will be the responsibility of the parents. They will be instructed to complete an online questionnaire daily, which will allow data collection to assess the efficacy and safety variables.

Being tested
Probiotic - Lacticaseibacillus rhamnosus CRL1505, Placebo
Keywords
prevention, upper respiratory tract infections, probiotics, microbiota, microbiome, children
Medical subject headings
Respiratory Tract Infections

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Probiotic - Lacticaseibacillus rhamnosus CRL1505Dietary supplement

    The probiotic product is provided in 2g sticks containing the strain Lacticaseibacillus rhamnosus CRL1505 at a concentration of ≥ 1.0E+8 CFU/g, with corn starch and maltodextrin as excipients.

  • PlaceboDietary supplement

    The placebo product is provided in 2g sticks of corn starch and maltodextrin.

Study groups in NCT07154992
Study groupRoleWhat they receive
PROBIOTICExperimentalNot described
Receives: Dietary Supplement: Probiotic - Lacticaseibacillus rhamnosus CRL1505
PLACEBOPlacebo comparatorNot described
Receives: Dietary Supplement: Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Patients who were diagnosed with at least 1, 2 or 3 URTIs

    Difference in the proportion of patients who were diagnosed with at least 1, 2 or 3 URTIs during the intervention (12 weeks) and follow-up period (16 weeks) between the study groups

    Measured: 12 and 16 weeks

  2. Number of URTIs per patient

    Difference in the mean number of URTIs per patient between the study groups during the intervention period (12 weeks) and follow-up period (16 weeks)

    Measured: 12 and 16 weeks

  3. Patients who were diagnosed of common cold and influenza

    Difference in the proportion of patients who were diagnosed of common cold and influenza during the intervention (12 weeks) and follow-up period (16 weeks) between the study groups.

    *This analysis will only be performed if a considerable number of URTIs other than the common cold are recorded.

    Measured: 12 and 16 weeks

Secondary outcomes (13)
  1. Participants who presented URTI complications

    Difference in the proportion of participants who experienced URTI complications (bacterial superinfections such as pneumonia, otitis media, and acute sinusitis) during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  2. Number of days with a URTI episode per participant

    Difference in the average number of days with a URTI episode per participant (days with URTI/participants) during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  3. Number of days until the first URTI

    Difference in the average number of days until the onset of the first URTI episode during the intervention period (12 weeks) between the study groups.

    Measured: 12 weeks

  4. Duration of each URTI episode

    Difference in the average duration of each URTI episode (mean ratio of days with URTI/URTI episodes for each participant) during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  5. URTI-free time rate

    Difference in the URTI-free time rate (proportion of accumulated days in which participants do not experience URTI relative to the total number of days) during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  6. Score of each symptom evaluated on the Jackson scale

    Difference in the average score of each symptom evaluated on the Jackson scale per day of common cold episode during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    The Jackson scale (also known as Jackson criteria or Jackson score) is a tool used to assess and quantify the symptoms of upper respiratory tract infections (URTI), such as the common cold

    It evaluates 8 main symptoms:

    Sneezing, Nasal discharge (runny nose), Nasal congestion, Sore throat, Cough, Headache, Malaise, Chilliness/feverishness

    Each symptom is scored on a 0-3 scale:

    0 = absent

    1. = mild
    2. = moderate
    3. = severe

    Criteria for defining a "cold episode" (URTI case) according to Jackson:

    At least 2 consecutive days with ≥2 of the following symptoms: runny nose, sore throat, sneezing. Or 1 of these symptoms plus at least one systemic symptom (headache, malaise, chilliness/feverishness).

    Measured: 12 and 16 weeks

  7. Number of days with fever per participant

    Difference in the average number of days with fever per participant during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  8. Participants who received antibiotic treatment

    Difference in the proportion of participants who received antibiotic treatment during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  9. Number of days with antibiotic treatment per participant

    Difference in the average number of days with antibiotic treatment per participant during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  10. Proportion of URTI episodes in which participants received symptomatic medication

    Difference in the proportion of URTI episodes in which participants received symptomatic medication (to relieve URTI symptoms) during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  11. Proportion of URTI days in which participants received symptomatic medication

    Difference in the proportion of URTI days in which participants received symptomatic medication (to relieve URTI symptoms) during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  12. Participants who experienced gastrointestinal infections

    Difference in the proportion of participants who experienced gastrointestinal infections during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

  13. School absence rate

    Difference in the school absence rate (proportion of accumulated school absence days due to URTI relative to the total number of days) during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.

    Measured: 12 and 16 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted4 Sep 2025
  2. Study start17 Dec 2024
  3. Primary completionMar 2027 (estimated)
  4. Study completionApr 2027 (estimated)

Resources

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
Prevention
Allocation
Randomised
Intervention model
Parallel groups
Masking
Double blind
Who is masked
Participant, Investigator
Enrolment
268 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07154992
Sponsor's protocol ID
IRESP.PROB-2
Status last verified
Aug 2025
First submitted
27 Aug 2025
Last updated
12 Sep 2025
Results posted
No
FDA-regulated drug
No
FDA-regulated device
No

Questions about this trial

What is this clinical trial studying?

A study testing Probiotic - Lacticaseibacillus rhamnosus CRL1505 in people with Upper Respiratory Tract Infection and Prevention, run by Bioithas SL at 1 site in Spain.

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 2 inclusion and 5 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: looking for participants now, as of the sponsor's last update on 12 Sep 2025. 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 Spain. 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. Some participants in this study may receive a placebo. 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 Juan Gabriel Agüera Santos (+34623022586, juan.aguera@bioithas.com), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Patients who were diagnosed with at least 1, 2 or 3 URTIs (time frame: 12 and 16 weeks). The study lists 3 primary outcomes in all. 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 12 Sep 2025.

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