After the best part of a decade of experimentation, the results are in: oxytocin, the naturally-occurring hormone that promotes social bonding, has no benefit for children with autism. A large study published this week in the New England Journal of Medicine revealed the much-hyped potential treatment to be a dead end.
“There was a great deal of hope this drug would be effective,” said principal investigator and lead author, Linmarie Sikich, in a statement. “All of us on the study team were hugely disappointed, but oxytocin does not appear to change social function of people with autism.”
Oxytocin is known as the “love hormone.” It’s the chemical that makes us find someone attractive, helps us (assuming things go well) enjoy orgasms with them, and then bond with the baby that Mother Nature hopes will result. It also helps us form friendships, playing an important role in promoting things like social interaction, communication, and cooperation. Autism spectrum disorders (ASD), on the other hand, are typically marked by the opposite: an impaired ability for social interaction. Classically, people with ASD can have trouble with things like eye contact, conversation, and many other intricacies of communication.
In other words, you can see why scientists connected the two. Some smaller studies seemed to back up the hunch too, suggesting that oxytocin could improve social and cognitive function for some children with ASD – others, however, seemed to show no impact at all. Despite the mixed results, many people with ASD have been prescribed the hormone to improve their social functioning. However, this paper now shows that while it probably did no harm, it also probably didn’t do much good either.
“Thousands of children with autism spectrum disorder were prescribed intranasal oxytocin before it was adequately tested,” said senior author Jeremy Veenstra-VanderWeele. “Thankfully, our data show that it is safe. Unfortunately, it is no better than placebo when used daily for months.”
The study followed 290 children aged between 3 and 17. Over 24 weeks, participants in the test group received a daily dose of oxytocin via a nasal spray, while the control group received a placebo spray. In the beginning, midway point, and end of the regimen, the children’s social skills were screened by the researchers and parents using standard analytic tools for ASD.
Researchers found that the oxytocin treatment showed no benefit. Children in the test group did show a slight improvement in social interaction compared to the control group, but by such a small amount it was statistically insignificant. Other outcomes, both good and bad, were basically the same over the two groups too.
Is this the end for oxytocin as a potential medication for people with autism? It’s complicated. The consensus of the research team, Sikich said, was that they found “no evidence … strong enough to justify more investigation of oxytocin as a treatment for autism spectrum disorders.”
However, in a companion piece, UCLA neurology professor Daniel H. Geschwind wrote that the various origin points of autism, plus certain nuances of the study methodology, would make it “premature to summarily reject the oxytocin signaling pathway (or efforts to increase social motivation in general) as a potential treatment target in autism spectrum disorder."
Either way, Veenstra-VanderWeele believes there’s one lesson from the study that’s particularly important: "Clinicians and families should insist that there is strong evidence for the safety and benefit of new treatments before they are provided to patients in the clinic,” he said.