Experimental drug reduces autism symptoms in mouse study

NEW YORK — A depression drug from Pfizer reduced signs of autism in mice in a study, a finding that may shed light on the cause of the disorder and jump-start research into ways to treat it.

The experimental treatment, GRN-529, targets the brain chemical glutamate, tied to socialization and behavior. When given to mice displaying signs of autism, it suppressed repetitive actions and anti-social behavior, according to the research published in the journal Science Translational Medicine. Pfizer and the National Institutes of Health funded the study.

There are no drugs on the market or in human testing to treat the symptoms or causes of autism, said Daniel Smith, an autism researcher at Pfizer. Until recently, scientists believed the brains of autistic patients were hard-wired before diagnosis, making treatment with a drug difficult. That changed with findings the disorder may be caused by malfunctioning genes that have a real-time effect on the brain, said Smith, a co-author of the study.

“It is only in the past five years that there have been large human studies identifying the genetic mutations linked to autism,” Smith said in a telephone interview. “From that we can now explore those genetic pathways in more detail.”

In the latest research, mice that were given the Pfizer drug displayed less repetitive grooming and jumping, and spent more time interacting with other animals.

Autism, a disorder that may affect one in 88 U.S. children, hurts brain development and is linked to poor social interaction and communication skills, repeated body movements, and unusual attachments to objects.

Pfizer, based in New York, plans to continue studying the drug in animals, Smith said.

Novartis AG and Roche Holding AG, both based in Basel, Switzerland, and the closely held U.S. company Seaside Therapeutics LLC are testing similar medicines in humans with fragile X syndrome, a genetic condition characterized by mental retardation, behavior problems, and delayed speech.

About 30 percent of patients with fragile X meet the diagnostics criteria for autism, the study said.