“Functional effects of the human gut microbiome on autism"

Projects had to focus on the clinical effects of different microbiota interventions (such as antibiotics, FMT, diet, probiotics, etc.) in patients with autism.


Pr Richard DELORME

Pr Richard DELORME
Head of Department of Child and Adolescent Psychiatry &
Excellence centre for autism and neurodevelopmental disorders (InovAND)
Robert Debré Hospital – Paris – France

“Randomized controlled trial evaluating the effect of transplantation of fecal microbiota in children with autism spectrum disorders and gastrointestinal symptoms”


Autism Spectrum Disorders (ASD), which affect approximately 1% of the general population, are characterized by impairments in social communication associated with repetitive/stereotyped behaviors. Approximately in third of these patients display gastrointestinal (GI) symptoms, and a growing number of studies suggests abnormalities of gut microbiota in ASD. Gut microbiota and the brain interact through complex pathways. Preliminary evidence in adults and children with ASD suggest that modulation of microbiota by probiotics and/or prebiotics and more recently by fecal microbiota transplantation could improve GI symptoms but also socio-communication deficit, with consistent improvement at year 2.

We hypothesized that early FMT in children ASD will significantly modify their GI symptoms and their clinical trajectory. We will thus perform a phase II controlled, randomized, double- blind clinical trial in children with ASD and GI symptoms, aged 36 to 72 months.

We mainly anticipate a decrease of GI symptoms in the FMT group, with a consistent effect 2 years after the treatment. Moreover, a decrease in autistic core symptoms is also expected. This clinical improvement should enhance access to learning and increase quality of life. These results would support an innovative and personalized therapeutic strategy for GI symptoms in a context of a lack of treatment and an urge for expectations from families. Finally, we aim also at identifying biomarkers of FMT response and reinforce the hypothesis of GM implication in ASD.