The Effect of a Multispecies Probiotics on Autism Symptoms in Children (PROBAUT)

In this trial, the investigators aim to evaluate the impact of a multispecies probiotic consisting of Bacillus subtilis W201, Bifidobacterium infantis W17, Bifidobacterium lactis W51, Lactobacillus acidophilus W37, Lactobacillus brevis W63, Lactobacillus rhamnosus W140, Lactococcus lactis W19, Propionibacterium freudenreichii W200, on the severity of autism symptoms, quality of life, gastrointestinal symptoms, sleep disturbances, parental stress levels and urinary p-cresol concentrations in children with Autism Spectrum Disorder aged 7 to 15 years.

Study Overview

• Status: Recruiting
• Conditions: Autism Spectrum Disorder
• Intervention / Treatment: Dietary supplement: Multispecies probiotics; Other: Placebo

Detailed Description

This study is a randomized, double-blind, placebo-controlled clinical trial. One hundred and ten children aged 7 to 15 years diagnosed with Autism Spectrum Didorder will be randomly assigned in a 1:1 ratio to receive either a multispecies probiotics or a placebo for 12 weeks. The probiotic mixture contains 5 x 10^9 colony forming units per dose consisting of Bacillus subtilis W201, Bifidobacterium infantis W17, Bifidobacterium lactis W51, Lactobacillus acidophilus W37, Lactobacillus brevis W63, Lactobacillus rhamnosus W140, Lactococcus lactis W19, Propionibacterium freudenreichii W200.

The primary outcome will be the assessment of core autism symptoms using the Autism Symptom Rating Scales (ASRS). The secondary outcomes will include: the quality of life measured by the Quality of Life in Autism Part A questionnaire (QoLA-A), evaluations of sleep impairments using Children Sleep Habit Questionnaire - Abbreviated (CSHQ-A), parental stress levels using Parenting Stress Index-III (PSI-III), gastrointestinal symptoms using Gastrointestinal Symptom Rating Scale (GSRS), and urinary p-cresol levels. These outcomes will be assessed twice: at baseline and after 12 weeks of intervention.

• Study Type: Interventional
• Enrollment (Estimated): 110
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Maja Kotowska, MD; Phone Number: +48223179536; Email: kotowska.maja@gmail.com
• Study Contact Backup: Name: Jan Łukasik, MD, PhD; Phone Number: +48223179536; Email: jan.lukasik@wum.edu.pl

Study Locations

• Poland
  • Warsaw
    • Warsaw, Warsaw, Poland, 02-091
      • Recruiting
      • Department of Paediatrics, The Medical University of Warsaw
      • Contact: Maja Kotowska, MD; Phone Number: +223179444; Email: maja.kotowska@uckwum.pl

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Diagnosis of ASD according to the Diagnostic and Statistical Manual of Mental Disorders, the fifth edition (DSM-5) or International Classification of Diseases, Tenth Revision (ICD-10).
2. Children either not taking any medication or receiving the same medication for the last 2 months.
3. Patients, or their parents/caregivers, are willing to provide written informed consent, proceed with nutritional supplements throughout the 3-month trial, refrain from starting any kind of special diet for the duration of the study, and complete the questionnaires at two time points during the study.

Exclusion Criteria:

1. Use of antibiotics in the previous 2 months before enrolling (excluding topical antibiotics).
2. Use of probiotics or synbiotics within the previous 2 months.
3. History of intolerance or allergy to probiotics, synbiotics or any other study product component.
4. Surgery with bowel resection or short bowel syndrome.
5. Children with severe immunodeficiency.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Multispecies probiotics group; 55 participants	Dietary supplement: Multispecies probiotics; Multispecies probiotics consisting of Bacillus subtilis W201, Bifidobacterium infantis W17, Bifidobacterium lactis W51, Lactobacillus acidophilus W37, Lactobacillus brevis W63, Lactobacillus rhamnosus W140, Lactococcus lactis W19, Propionibacterium freudenreichii W200 at a dose of 5x10^9 Colony Forming Units (CFU), once daily, orally.
Placebo Comparator: Control group; 55 participants	Other: Placebo; Placebo identical in taste, smell and color to the multispecies probiotics.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Autism Spectrum Rating Scales (ASRS)	Assessment of the severity of ASD symptoms. Scores are reported as percentiles, with higher values indicating greater symptom severity.	0-3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
P-cresol levels in urine samples	Assessment of the level of p-cresol in urine samples.	0-3 months
The Quality of Life in Autism Part A (QoLA-A)	Assessment of the quality of life of parents of children with ASD. Scores range from 28 to 140 points, with higher values reflecting a better quality of life.	0-3 months
The Parenting Stress Index, 4th Edition (PSI-4) / SIPA (Stress Index for Parents of Adolescents)	Assessment of the parenting stress intensity. The level of parental stress will be assessed using the PSI-4 questionnaire if the child is under 11 years old, or the SIPA if the child is 11 years or older. Scores range from 101 to 505 points for the PSI-4 and 90 to 450 points for the SIPA. Higher scores indicate higher level of stress.	0-3 months
Children Sleep Habit Questionnaire - Abbreviated (CSHQ-A)	Assessment of the sleep impairments. Scores range from 0 to 154 points, with higher values indicating a greater severity of sleep disturbances.	0-3 months
Gastrointestinal Symptom Rating Scale (GSRS)	Assessment of the severity of gastrointestinal symptoms. Scores range from 15 to 105 points, with higher values indicating greater severity of gastrointestinal symptoms.	0-3 months

Collaborators and Investigators

• Sponsor: Medical University of Warsaw
• Collaborators: Winclove Probiotics B.V.
• Investigators: Principal Investigator: Maja Kotowska, MD, Department of Paediatrics, The Medical University of Warsaw, Poland

Publications and helpful links

General Publications

• Kotowska-Babol M, Konowalek L, Szajewska H, Lukasik J. Effect of multispecies probiotics on autism symptoms: protocol for a randomized controlled trial (PROBAUT). Trials. 2025 Dec 20. doi: 10.1186/s13063-025-09373-w. Online ahead of print.

Study record dates

Study Major Dates

• Study Start (Actual): August 7, 2024
• Primary Completion (Estimated): July 1, 2026
• Study Completion (Estimated): July 30, 2026

Study Registration Dates

• First Submitted: June 3, 2024
• First Submitted That Met QC Criteria: June 3, 2024
• First Posted (Actual): June 7, 2024

Study Record Updates

• Last Update Posted (Actual): January 8, 2026
• Last Update Submitted That Met QC Criteria: January 5, 2026
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: Probiotics; Autism Spectrum Disorder
• Additional Relevant MeSH Terms: Mental Disorders; Neurodevelopmental Disorders; Child Development Disorders, Pervasive; Autism Spectrum Disorder
• Other Study ID Numbers: KB/151/2023

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No