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Thursday, November 26, 2020

Looking for Autism Biomarkers

Uncertainty is the major theme of The Politics of Autism.  

 Brita Belli at Yale:

Five years ago, a Yale-led partnership launched a landmark study to identify the biomarkers, or biological indictors, of autism that could help diagnose, track, and assess treatments in patients.

Since then, the Autism Biomarkers Consortium for Clinical Trials has discovered the first two biomarkers for any psychiatric disorder to be accepted into the U.S. Food and Drug Administration’s (FDA) Biomarker Qualification Program, an advance that could lead to new treatments through drugs and other interventions.

The study recently received $39 million for a second phase in which researchers will seek to replicate the findings of the first phase and test a younger group of preschool-aged children. The next stage will begin in the new year.

“Everything we do to treat autism is currently based on clinical subjective decisions,” said James McPartland, professor in the Yale Child Study Center and of psychology, who has led the study for the past five years and will direct the renewal. “It’s not the same as making decisions based on biology.”

Autism affects 1 in 54 children in the U.S., including 1 in 34 boys, according to the Centers for Disease Control and Prevention.

In the initial study, the largest of its kind in this country, researchers tested nearly 400 children, 280 with autism and 119 with typical development. The participants were aged 6 to 11 and represented a wide range of IQs.

To identify the biomarkers, the researchers used one of the oldest methods of brain imaging — electroencephalography (EEG) — in which brain activity is measured through the placement of electrode sensors on the scalp, as well as eye tracking.

At three different times, scientists measured how the children responded to various cues. Both of the biomarkers they discovered were related to how children with autism responded to human faces; one involved the brain’s neural processing of a face, the other measured the child’s visual attention to people. “Children with autism showed slower than expected brain responses to faces and paid less attention to faces,” McPartland said.

They were the first two biomarkers for a neurodevelopmental disorder or psychiatric condition accepted to the FDA’s Center for Drug Evaluation and Research Biomarker Qualification Program. The researchers are now working with the FDA to develop methods for evaluating additional biomarkers for these types of disorders.

In the second phase, researchers will follow up with the same group of children evaluated during the first phase, who are now 11 to 16 years of age, to see whether the biomarkers have remained stable and whether they might predict subsequent outcomes in the child’s life. In addition, they will also evaluate these biomarkers in a group of younger children — ages 3 to 5 — both with and without autism.

McPartland, who is director of the Yale Developmental Disabilities Clinic, said this research offers new possibilities for treating autism. “These are considered intervention and drug development tools,” he said of the biomarkers. “The field doesn’t have a way of measuring how treatments affect autism except through clinical observation. We hope these will be sensitive biological measures to achieve this goal.”

In addition to the potential for drug companies and intervention developers to identify treatments for autism, McPartland said the biomarkers may offer clinicians a better understanding of how behavioral and therapeutic tools might benefit children with autism and which patients might benefit the most.