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

Not Applicable

Recruiting

• Conditions: Upper Respiratory Tract Infection; Prevention

• Registration Number: NCT07154992
• Lead Sponsor: Bioithas SL

Brief 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.

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.

Study Timeline

• Study Start: 2024-12-17
• Status Verified: 2025-08
• Study First Submitted: 2025-08-27
• Study First Submitted QC: 2025-08-27
• Last Update Submitted: 2025-08-27
• Study First Posted: 2025-09-04
• Last Update Posted: 2025-09-04
• Primary Completion: 2027-03
• Study Completion: 2027-04-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 268

Inclusion Criteria

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

Exclusion Criteria

• 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.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Patients who were diagnosed with at least 1, 2 or 3 URTIs	12 and 16 weeks	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
Number of URTIs per patient	12 and 16 weeks	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)
Patients who were diagnosed of common cold and influenza	12 and 16 weeks	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.

Secondary Outcome Measures

Name	Time	Method
Participants who presented URTI complications	12 and 16 weeks	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.
Number of days with a URTI episode per participant	12 and 16 weeks	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.
Number of days until the first URTI	12 weeks	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.
Duration of each URTI episode	12 and 16 weeks	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.
URTI-free time rate	12 and 16 weeks	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.
Score of each symptom evaluated on the Jackson scale	12 and 16 weeks	Difference in the average score of each symptom evaluated on the Jackson scale (sore throat, nasal congestion, runny nose, cough, sneezing, headache, muscle pain, chills) per day of common cold episode during the intervention period (12 weeks) and the total follow-up period (16 weeks) between the study groups.
Number of days with fever per participant	12 and 16 weeks	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.
Participants who received antibiotic treatment	12 and 16 weeks	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.
Number of days with antibiotic treatment per participant	12 and 16 weeks	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.
Proportion of URTI episodes in which participants received symptomatic medication	12 and 16 weeks	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.
Proportion of URTI days in which participants received symptomatic medication	12 and 16 weeks	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.
Participants who experienced gastrointestinal infections	12 and 16 weeks	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.
School absence rate	12 and 16 weeks	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.

Trial Locations

Locations (1)

MiBioPath Research Group (UCAM); 🇪🇸 Murcia, Spain