New research suggests that medications targeting a hormone may lead to improved socialization and behavior in those with autism.

Results from two studies on treatments related to the hormone vasopressin — one looking at adults on the spectrum and another looking at children — are showing promise.

“We might finally have an agent that will target these core features that are very hard to treat,” said Antonio Hardan, a professor of psychiatry and behavioral sciences at Stanford University and a senior author of the research looking at kids.

For the children’s study, 30 kids ages 6 to 12 with autism were randomly assigned to take a vasopressin nasal spray or a placebo each day for four weeks. Each child’s autism symptoms were assessed using several measures before and after the trial.

Parents and researchers observed greater increases in social abilities in those who took vasopressin, according to findings being published this week in the journal Science Translational Medicine. These children also performed better on lab tests designed to measure social capabilities and they displayed less anxiety.

The improvements were greatest among kids who had the highest levels of vasopressin before the study began, the researchers found. What’s more, in these youngsters, the treatment also appeared to diminish restricted and repetitive behaviors.

Meanwhile, a separate study involving 223 adult men with moderate to severe autism assessed a drug called balovaptan, which affects the brain’s response to vasopressin. The men were assigned to one of four groups, either receiving various doses of balovaptan or a placebo for 12 weeks.

The adult trial showed no meaningful gains when participants were assessed using the Social Responsiveness Scale, a common measure for social impairment in those with autism. However, the two groups that received higher doses of the drug showed gains on a second scale examining socialization, adaptive behavior and daily living skills compared to those who received the placebo, according to findings which are also being published this week in the journal Science Translational Medicine.

“Both drugs were well tolerated and had an acceptable safety profile, suggesting that modulating the vasopressin pathway may be a useful therapeutic strategy for ASD,” researchers behind both studies wrote in the journal.

Last year, the Food and Drug Administration granted balovaptan its breakthrough therapy designation, which offers extra assistance and priority from regulators to accelerate the development of promising treatments. At the time, drug maker Roche said the medication has the potential to improve “core social interaction and communication” in those with autism.

Researchers behind the study looking at children are now working to reproduce their findings in another 100 kids.

“Before getting too excited, I want us to replicate this, and more importantly I want others to replicate our findings,” said Hardan who indicated that larger trials are necessary to make sure that the treatment is safe.