Follow-up finds durable benefit of microbiota transplant for autism symptoms

Last Updated: 2019-04-17

By Anne Harding

NEW YORK (Reuters Health) - Children with autism spectrum disorder (ASD) continue to show improvements in autism symptoms and gastrointestinal symptoms two years after undergoing microbiota-transfer therapy (MTT), a new follow-up study shows.

"Although it's an open-label study, it does appear that there's a large improvement in GI symptoms and a substantial improvement in autism symptoms long-term, lasting up to two years after treatment," Dr. James B. Adams of Arizona State University in Tempe, the principal investigator on the study, told Reuters Health by phone. "It appears to be generally safe, and with minimal side effects."

The original study (https://bit.ly/2Ghjn2K) included 18 patients with ASD, who underwent antibiotic treatment, a bowel cleanse and stomach-acid suppression, followed by fecal-microbiota transplant. All participated in the follow-up study. "We're using the vancomycin to uproot all the weeds, the bad bacteria, and then we're re-seeding for good bacteria," Dr. Adams explained.

Patients had a 58% reduction in Gastrointestinal Symptom Rating Scale (GSRS) scores and a 26% drop in the proportion of days in which they had abnormal stools at follow-up, similar to the improvements observed soon after MTT.

Based on the Childhood Autism Rating Scale (CARS), ASD severity was 47% lower than at baseline (P<0.001), while it had been 23% lower 10 weeks after MTT, the team reports in Scientific Reports, online April 9.

At baseline, 83% had severe ASD based on CARS, while at two years 17% were considered to have severe ASD, 39% mild to moderate ASD and 44% had scores below the cutoff for an ASD diagnosis.

Patients also showed improvements in parent-reported Social Responsiveness Scale (SRS) and Aberrant Behavior Checklist (ABC) scores. Improvements in GSRS correlated with improvements in CARS, SRS and ABC scores.

Fecal bacterial diversity remained higher than at baseline in the 16 patients who provided fecal samples, and some had microbiota that were more diverse at the two-year follow-up point than when they were assessed at 18 weeks after MTT.

"We were just so pleasantly surprised to see that family after family, most of the families, just reported a slow, steady improvement," Dr. Adams said. He noted that he and his colleagues had not planned to do a follow-up of the study, but decided to do so after three different families approached him to tell him how well their children were doing.

"This study was just our first guess at dosing and our first guess about duration," he added. "Most of the children had substantial improvements. A few sadly did not. Maybe we just need a higher dose or duration for some of them.

Dr. Adams and his team are currently conducting a phase 2 trial of MTT in adults with autism.

SOURCE: https://bit.ly/2IKRumL

Sci Rep 2019.