Researchers at Arizona State University (ASU) have demonstrated long-term beneficial effects for children diagnosed with autism spectrum disorders (ASD) through a revolutionary technique known as microbiota transfer therapy (MTT). The study named “Long-term benefit of Microbiota Transfer Therapy in Autism Symptoms and Gut Microbiota” was published in the latest edition of Scientific Reports.
MTT is a special type of faecal transplant originally pioneered by Dr. Thomas Borody, an Australian gastroenterologist.
The MTT approach used in the study involved 10 weeks of treatment, including pre-treatment with vancomycin, a bowel cleanse, a stomach acid suppressant, and fecal microbiota transfer daily for seven to eight weeks.
The initial study conducted in 2017 involving 18 participants had found that the extended duration treatment protocol gave a promising approach to alter gut microbiome and improve gastrointestinal and behavioural symptoms of ASD. The study was published in the journal Microbiome.
The current study has shown that the benefits of the treatment are extended beyond eight weeks to, at least, two years post-treatment.
“We are finding a very strong connection between the microbes that live in our intestines and signals that travel to the brain,” said lead researcher, Krajmalnik-Brown, a professor at the Biodesign Swette Center for Environmental Biotechnology at the Biodesign Institute and ASU’s School for Sustainable Engineering and the Built Environment in a news release. “Two years later, the children are doing even better, which is amazing.”
The researchers from ASU compared differences in the microbiome of children with autism to typically developing children. At the beginning of the study children with autism had shown a lower diversity in their respective gut microbiomes. They lacked strains of beneficial bacteria such as Bifidobacteria and Prevotella.
“Kids with autism are lacking important beneficial bacteria and have fewer options in the bacterial menu of important functions that bacteria provide to the gut than typically developing kids,” Krajmalnik-Brown said.
FMT (faecal microbiota transplant) treatment substantially enhanced microbial diversity and the presence of beneficial bacteria in the gut, such as Bifidobacteria and Prevotella. After two years, diversity was even higher, and the presence of beneficial microbes prevailed.
“Understanding which microbes and chemicals produced by the microbes are driving these behavioral changes is at the heart of our work,” said Krajmalnik-Brown.
“Many kids with autism have gastrointestinal problems, and some studies, including ours, have found that those children also have worse autism-related symptoms,” he said. “In many cases, when you are able to treat those gastrointestinal problems, their behavior improves.”
The study demonstrated that two years after treatment stopped the participants still had an average of a 58% reduction in GI symptoms compared to baseline.
Researchers reported a 45% decrease in ASD symptoms compared to baseline. At the start of the study, 83% of participants were rated to have severe autism. At the end of the study, only 17% were severe, 39% were found to have moderate, and 44% were below the cut-off for moderate ASD.
Currently, effective treatments for ASD include behavioral therapy, speech and social therapy, psychiatric medications, and dietary and nutritional approaches. However, no medical treatments have been approved to treat core symptoms of ASD such as social communication difficulties and repetitive behaviors.
“This is a world-first discovery that when we treated the gut bacteria in these children during our clinical trial two years ago to reset their microbiome with FMT, positive results are still continuing to be improving two years from the original treatments. I would call it the highest improvement in a cohort that anyone has achieved for autism symptoms,” said Borody.
The researchers are now working on optimizing the dosage and duration of the treatment to improve benefits and determine if booster doses may be needed in certain cases.