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Study on the Effects and Safety of Fecal Microbiota Transplant in Children with Autism and Digestive Issues

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on children with autism spectrum disorder who also experience digestive issues like diarrhea, abdominal pain, constipation, indigestion, or reflux. The study will use a treatment called an enema transplant of fecal microbiota, which involves introducing healthy bacteria from a donor into the child's digestive system through the rectum. This treatment is also known by the code name MaaT 033.

The purpose of the study is to evaluate the effect and safety of this treatment in improving digestive symptoms in children with autism. The study will follow the children over a period of time to see if their digestive symptoms improve and to monitor any side effects. The treatment will be given over a maximum period of 14 days, and the children's progress will be checked at various points, including 18 weeks after the start of the study.

Throughout the study, parents and healthcare professionals will use different questionnaires and scales to assess changes in the children's digestive symptoms and overall well-being. The study aims to see if there is a significant reduction in digestive issues and any improvement in the core symptoms of autism. The results will help determine if this treatment could be a beneficial option for children with autism and digestive problems.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, the child must have a diagnosis of autism spectrum disorder (ASD) based on DSM-5 criteria. The child should also have experienced gastrointestinal symptoms such as diarrhea, abdominal pain, constipation, indigestion, or reflux for over a year.

    The child must be between 36 and 72 months old. Consent from all legal guardians is required, and the child must be affiliated with social insurance.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to evaluate the child's gastrointestinal symptoms using the Gastrointestinal Symptoms Rating Scale (GSRS). This scale measures the intensity of symptoms like diarrhea, abdominal pain, constipation, indigestion, and reflux.

  3. Step 3

    Fecal microbiota transplantation (FMT)

    The child will receive a treatment called fecal microbiota transplantation (FMT). This involves the use of an enema containing allogeneic fecal microbiota, which is a mixture of healthy bacteria from a donor. The enema is administered rectally.

    The product used is called enema transplant of fecal microbiota 25g/100mL. The frequency and duration of administration will be determined by the study protocol.

  4. Step 4

    Monitoring and follow-up

    The child's progress will be monitored at various intervals: at the start of the study (week 0), week 4, week 18, week 24, and month 12.

    Parents will evaluate the child's gastrointestinal symptoms using the GSRS, and the child's overall improvement will be assessed through multiple questionnaires and scales.

    The Pediatric Adverse Event Rating Scale will be used to monitor any side effects from the FMT process. This will be evaluated by a pediatrician on day 0, day 5, week 4, week 18, week 24, and month 12.

  5. Step 5

    Evaluation of outcomes

    The primary goal is to determine if there is a reduction of more than 50% in the GSRS composite score by week 18.

    Secondary outcomes include improvements in autistic core symptoms and global improvement, adherence to instructions during the FMT process, and quality of life assessments using the Pediatric Quality of Life Inventory (PedsQL) at week 0, week 18, and month 12.

Who can join the trial?

5 criteria

  • Must have a diagnosis of autism spectrum disorder (ASD) based on the DSM-5 criteria. The DSM-5 is a manual used by healthcare professionals to diagnose mental disorders.
  • Must have gastrointestinal symptoms such as diarrhea, abdominal pain, constipation, indigestion, or reflux, with a score of 5 or more in one of these areas for over a year. Gastrointestinal symptoms refer to problems related to the stomach and intestines.
  • Must be between 36 and 72 months old (3 to 6 years old).
  • Must have consent from all legal guardians. This means that all parents or legal guardians agree to the child's participation in the study.
  • Must have social insurance affiliation. This means being part of a social insurance program.

Who cannot join the trial?

10 criteria

  • Children who are not between the ages of 36 to 72 months (3 to 6 years old) cannot participate.
  • Children who do not have an autism spectrum disorder cannot participate. Autism spectrum disorder is a condition that affects how a person communicates and interacts with others.
  • Children who have any other medical conditions that might interfere with the study cannot participate.
  • Children who are not able to follow the study procedures cannot participate.
  • Children who have participated in another clinical trial recently cannot participate.
  • Children who have had a fecal microbiota transplantation before cannot participate. Fecal microbiota transplantation is a procedure where healthy bacteria from a donor's stool are placed into another person's gut to help improve their gut health.
  • Children who have a history of severe allergies or reactions to medications or treatments cannot participate.
  • Children who are taking medications that might interfere with the study cannot participate.
  • Children who have a history of certain gastrointestinal diseases cannot participate. Gastrointestinal diseases affect the stomach and intestines.
  • Children who have a compromised immune system cannot participate. A compromised immune system means the body's defense against infections is weakened.
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Investigated drugs

Fecal Microbiota Transplantation is a therapy being studied in this trial. It involves taking healthy bacteria from the stool of a donor and placing it into the gut of a patient. The goal is to help improve the balance of bacteria in the patient's intestines. In this study, researchers are looking at how this therapy might help children with autism spectrum disorders who also have problems with their digestion. They want to see if it can make their stomach and bowel symptoms better and if it is safe for them to use.

What is already known about the treatment

Fecal Microbiota Transplantation – This treatment involves transferring stool from a healthy donor into the gastrointestinal tract of a patient. It is currently being studied in clinical trials for its potential benefits in children with autism spectrum disorders who also have gastrointestinal symptoms. The main goal is to see if it can improve gut health and related symptoms. The treatment works by introducing beneficial bacteria into the gut, which can help balance the gut microbiome. It is classified under microbiome-based therapies.

Investigated diseases

Autism Spectrum Disorder – Autism Spectrum Disorder is a developmental condition that affects communication, behavior, and social interaction. It typically appears in early childhood, with symptoms often becoming noticeable by age two or three. Individuals with this disorder may have difficulty understanding social cues, forming relationships, and may engage in repetitive behaviors. The severity and combination of symptoms can vary widely among individuals. Over time, some children may show improvements in communication and social skills, while others may continue to face challenges. The progression of the disorder is unique to each individual, with some experiencing changes in symptoms as they grow older.
Trial detailsLast updated 2 Oct 2026
Age0-17PhasePhase IITrial ID2025-520539-17-00Protocol codeAPHP241418Estimated enrolment5 patientsSponsorAssistance Publique Hopitaux De Paris

sourced from the EU Clinical Trials Register and site verification

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