Balovaptan failed to improve socialization, communication in youth with ASD

While well tolerated, balovaptan did not improve socialization and communication difficulties in young persons with autism spectrum disorder compared with placebo, according to results of a clinical trial published in JAMA Psychiatry.

“Autism spectrum disorder is a common lifelong neurodevelopmental condition with an increasing global prevalence,” Eric Hollander, MD, of the department of psychiatry and behavioral sciences at Albert Einstein College of Medicine in New York, and colleagues wrote. “There is an unmet need for approved pharmacologic therapies targeting the suspected underlying biologic pathways associated with the core symptoms of ASD.”

Researchers aimed to assess the safety and efficacy of balovaptan (RG7314, Roche), an oral therapeutic and selective vasopressing 1a receptor antagonist compared with placebo in both children and adolescents with ASD.

The study was a randomized, double-blind, 24-week, parallel-group, placebo-controlled phase 2 trial, which occurred across 41 sites in the United States between 2016 and 2019. From 599 screened individuals, 339 individuals aged 5 to 17 years with an ASD diagnosis were selected for participation and were randomly assigned to either daily 4 mg or 10 mg adult-equivalent doses of balovaptan or placebo, until the 4 mg group was discontinued. The primary efficacy analysis population consisted of those assigned the 10 mg adult dose of balovaptan and those who received placebo. The primary end point was change from baseline on the Vineland-II two-domain composite (2DC) score at week 24.

Results showed no statistically significant differences between the balovaptan and placebo groups in change from baseline on the Vineland-II 2DC score at week 24 (difference in adjusted least-squares mean, 0.16; 90% CI, 2.56 to 2.23). No improvements for balovaptan compared with placebo were observed at week 24 for any secondary end points.

Researchers found balovaptan was well tolerated with no emerging safety concerns, as similar proportions of participants reported adverse events (balovaptan, 66 of 86 [76.7%] vs. placebo, 61 of 81 [75.3%]) and serious adverse events (balovaptan, 1 of 86 [1.2%] vs. placebo, 4 of 81 [4.9%]).

“Balovaptan appeared to be well tolerated in children older than 5 years in this study, and no safety signals were detected,” Hollander and colleagues wrote. “Results suggest that V1a receptor antagonism does not improve social and communication function in pediatric ASD.”