Effect of Limosilactobacillus Reuteri on Social Deficits in Children With Autistic Spectrum Disorder

September 28, 2026 updated by: BioGaia AB

Effect of Limosilactobacillus Reuteri on Social Deficits in Children With Autistic Spectrum Disorder: a Double-blind, Randomized, Placebo-controlled, Parallel-group Clinical Study

This is a double-blind, randomized, placebo-controlled, parallel-group study in children with Autism Spectrum Disorder (ASD) to evaluate the effect of a probiotic product on the ASD symptoms.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

200

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Sanna H Nystrom, PhD
  • Phone Number: +46761483866
  • Email: sny@biogaia.se

Study Contact Backup

  • Name: Anna Pauter, PhD
  • Phone Number: +46 76 328 04 77
  • Email: anp@biogaia.se

Study Locations

  • Argentina
    • Maipú
      • Mendoza, Maipú, Argentina, M5515DUF
        • Sanatorio Maipú
        • Contact:
        • Contact:
        • Principal Investigator:
          • Romina L Squartini, MD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

4 years to 12 years (Child)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Boys or girls aged between 4 to 12 years at screening.
  • ASD diagnosis confirmed by a qualified clinician according to DMS-5 criteria, M-CHAT used as a screening tool.
  • Parents/caregivers/legal guardians are ≥18 years.
  • Readiness and the opportunity for parents/caregivers/legal guardians to fill out a study diary, questionnaires, and report regularly during the intervention period.
  • Parents/caregivers/legal guardians with ability to understand and comply with the requirements of the study, as judged by the Investigator.
  • Parents/caregivers/legal guardians willing and able to give informed consent for their and their child's participation in the study.

Exclusion Criteria:

  • Neurological syndromes that could explain autism disorders.
  • Organic gastrointestinal disorders (e.g. IBD, peptic ulcers and cancer). Celiac disease is accepted
  • Any other severe clinically relevant disease or disorder which may affect the participation in the study, based on the investigator's judgement.
  • Allergy or intolerance to one of the excipients of the probiotic product.
  • Children with reported exposure to probiotic supplements in the 15 days prior to Screening Visit (V1).
  • Children with reported exposure to oral and/or systemic antibiotics in the 7 days prior to Screening Visit (V1).
  • Children with reported exposure to proton pump inhibitors in the 7 days prior to Screening Visit (V1).
  • Participation in other interventional clinical study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Probiotics

Probiotic oil drops formulation. Administered once daily.
Dietary supplement: Probiotics

Combination of L. reuteri strains.
Placebo Comparator: Placebo

Placebo oil drops formulation. Administered once daily.
Dietary supplement: Placebo

Placebo identical to the active product, except the addition of probiotics.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes in Social Responsiveness Scale-2 (SRS-2) score
Time Frame: From baseline to end of study (6 months)

Changes in the SRS-2 score in the L. reuteri group compared to the placebo group. The SRS-2 is a 65-item questionnaire, with higher scores indicating greater social impairment and severity of autism-related traits.
From baseline to end of study (6 months)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Autism Diagnostic Observation Schedule, 2nd Ed (ADOS-2) Calibrated Severity Score (CSS) for Social Affect
Time Frame: From baseline to end of study (6 months)

Change in ADOS-2 CSS for Social Affect in the L. reuteri group compared to the placebo group.

ADOS-2 is a semi-structured, standardized assessment that observes social interaction, communication, play, and restricted or repetitive behaviors across five modules tailored to age and language level. Higher scores indicate a higher level of autism-related behaviors.
From baseline to end of study (6 months)
Change in total Autism Diagnostic Observation Schedule, 2nd Ed (ADOS-2) score
Time Frame: From baseline to end of study (6 months)

Change in total ADOS-2 score in the L. reuteri group compared to the placebo group.

ADOS-2 is a semi-structured, standardized assessment that observes social interaction, communication, play, and restricted or repetitive behaviors across five modules tailored to age and language level. Higher scores indicate a higher level of autism-related behaviors.
From baseline to end of study (6 months)
Change in GI symptoms
Time Frame: From baseline to end fo study (6 months)

Change in GI symptoms, assessed by the 6 item Gastrointestinal Severity Index (6-GSI) in the L. reuteri group compared to the placebo group.

6-GSI is a six item questionnaire with total score 0-12 with higher scores indicating worse outcome.
From baseline to end fo study (6 months)
Change in ABAS-2 score
Time Frame: From baseline to end fo study (6 months)

Change in adaptive behaviour, assessed by the Adaptive Behavior Assessment System, Second Edition (ABAS-2) in the L. reuteri group compared to the placebo group.

ABAS-2 is a 4-point rating scale with the scoring system divided into skill area scores (range 1 to 19), domain scores (range 40 to 160) and general adaptive composite (40 to 150). A higher score indicates a better outcome.
From baseline to end fo study (6 months)
Proportion of responders
Time Frame: At 6 months

Proportion of responders at 6 months, evaluating all assessments and questionnaires, in the L. reuteri group compared to the placebo group.
At 6 months

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Family Quality of Life
Time Frame: From baseline to end fo study (6 months)

Change in family Quality of Life (QoL), assessed by the Pediatric Quality of Life Inventory™ Family Impact Module (PedsQL™ Family Impact Module), in the L. reuteri group compared to the placebo group.

The range of the total score is 0-100 with a higher score indicating a better outcome.
From baseline to end fo study (6 months)
Change in quality of sleep
Time Frame: From baseline to end of study (6 months)

Change in sleep quality, assessed by the Children's Sleep Habits Questionnaire, in the L. reuteri group compared to placebo.

The CSHQ is scored on 33 of 52 items, using a 1-3 scale, with total score range 33-99. A higher score indicates worse outcome and the cut-off of a total score of 41 or higher indicating potential sleep problems.
From baseline to end of study (6 months)
Impact of dietary habits
Time Frame: At baseline and end of study (6 months)

Impact of dietary habits, assessed by a Food Frequency Questionnaire (FFQ), on the gut microbiota profile and effect of the L. reuteri intervention.
At baseline and end of study (6 months)
Changes in gut microbiota structure and composition
Time Frame: Baseline, 3 and 6 months

Changes in the gut microbiota structure and composition and the effect of the L. reuteri intervention, assessed by metagenomic analysis of fecal samples
Baseline, 3 and 6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

BioGaia AB

Investigators

  • Principal Investigator: Romina L Squartini, MD, Sanatorio Maipú

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

October 15, 2026

Primary Completion (Estimated)

October 31, 2027

Study Completion (Estimated)

October 31, 2027

Study Registration Dates

First Submitted

September 22, 2026

First Submitted That Met QC Criteria

September 22, 2026

First Posted (Actual)

September 28, 2026

Study Record Updates

Last Update Posted (Actual)

September 30, 2026

Last Update Submitted That Met QC Criteria

September 28, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • CSUB0223

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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