Does Pregnenolone Adjunct to Risperidone Ameliorate Irritable Behavior in Adolescents With Autism Spectrum Disorder: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial?

Abstract

Objectives: Pregnenolone is a neurosteroid with modulatory effects on γ-aminobutyric acid neurotransmission. Here, we aimed to evaluate the effectiveness and safety of pregnenolone add-on to risperidone in adolescents with autism spectrum disorders (ASD).

Methods: Sixty-four ASD patients were randomly allocated to receive either pregnenolone (n = 32) or matching placebo (n = 32) in addition to risperidone. The Aberrant Behavior Checklist-Community Edition scale was used to evaluate the behavioral status of patients at baseline, week 5, and the trial end point. The change in score of irritability subscale was the primary outcome. Frequency of adverse effects due to trial medications was compared between the treatment groups.

Results: Fifty-nine patients completed the trial (30 in pregnenolone and 29 in the placebo arm). Baseline characteristics of both treatment groups were similar (P > 0.05). Repeated measures analysis was suggestive of greater exhibited improvement for the pregnenolone group on irritability, stereotypy, and hyperactivity subscales of the Aberrant Behavior Checklist-Community Edition over the trial period (F = 3.84, df = 1.96, P = 0.025; F = 4.29, df = 1.39, P = 0.029; F = 6.55, df = 1.67, P = 0.004, respectively). Nonetheless, the alterations in lethargy and inappropriate speech domains scores were similar for both arms (F = 0.93, df = 1.49, P = 0.375; F = 1.10, df = 1.60, P = 0.325, respectively). There was no significant difference in frequency as well as severity of adverse effects between the 2 groups.

Conclusions: Pregnenolone adjunct to risperidone could attenuate core features associated with ASD.