After several years of experimentation, the results of a large study published in the New England Journal of Medicine are here:oxytocin, the natural hormone that promotes social bonding, has no benefit for autistic children.
Studies have already shown the effects of oxytocin on confidence, social and reactivity to stress. Autism spectrum disorders (ASD), on the other hand, are usually marked by the opposite:an impaired ability to socially interact. Also, in recent years, several experimental studies and other small clinical trials have suggested that treatment with intranasal oxytocin can reduce social disturbances in people with autism spectrum disorders . But is this really the case? A recent study says no.
For this work, a team at Duke University Medical Center conducted a twenty-four-week Phase 2 trial of intranasal oxytocin treatment in 290 children and adolescents aged three to seventeen with autism spectrum disorders. All subjects were randomly and equally assigned to either an "oxytocin group" or a placebo group (stratified by age and fluency).
At the beginning, halfway and at the end of the diet, the social skills of the children were examined using standard analysis tools for ASDs. The primary outcome measure was the least-squares mean change from baseline on the Modified Social Withdrawal subscale of the Aberrant Behavior Checklist which consists of thirteen items (scores range from 0 to 39, higher scores indicating less social interaction). Secondary outcomes included two additional measures of social function and an abbreviated measure of IQ.
Result:Oxytocin treatment appeared to provide no benefit . The children in the test group indeed showed a very slight improvement in social interaction compared to the control group. However, the researchers consider this improvement to be statistically insignificant.
“There was a lot of hope that this drug would work “, explains Linmarie Sikich, lead author of the study. “All of us on the study team were extremely disappointed “.
The researchers also point out that the treatment also has no negative effects , which could reassure many concerned parents. “Thousands of children with autism spectrum disorders were prescribed intranasal oxytocin before it was properly tested “, continues the researcher. “Fortunately, our data shows that the molecule is safe. Unfortunately, it just doesn't do better than a placebo when used daily over several months “.
Is this the end of oxytocin as a potential drug for people with autism? Not for everybody. In a companion piece, UCLA neurology professor Daniel H. Geschwind argues that the different origin points of autism, as well as some nuances of the study methodology, make it "premature summary dismissal of oxytocin as a “potential target of treatment in autism spectrum disorders “.
