A pilot dose finding study of pioglitazone in autistic children.

Background: Pioglitazone is a promising compound for treatment of core autism spectrum disorder (ASD) symptoms as it targets multiple relevant pathways, including immune system alterations.

Objective: This pilot study aimed to elucidate the maximum tolerated dose, safety, preliminary evidence of efficacy, and appropriate outcome measures in autistic children ages 5-12 years old.

Methods: We conducted a 16-week prospective cohort, single blind, single arm, 2-week placebo run-in, dose-finding study of pioglitazone. Twenty-five participants completed treatment. A modified dose finding method was used to determine safety and dose response among three dose levels: 0.25 mg/kg, 0.5 mg/kg, and 0.75 mg/kg once daily.

Results: Maximum tolerated dose: there were no serious adverse events (SAEs) and as such the maximum tolerated dose within the range tested was 0.75 mg/Kg once daily. Safety: overall, pioglitazone was well tolerated. Two participants discontinued intervention due to perceived non-efficacy and one due to the inability to tolerate interim blood work. Three participants experienced mild neutropenia. Early evidence of efficacy: statistically significant improvement was observed in social withdrawal, repetitive behaviors, and externalizing behaviors as measured by the Aberrant Behavior Checklist (ABC), Child Yale-Brown Obsessive Compulsive Scale (CY-BOCS), and Repetitive Behavior Scale-Revised (RBS-R). Forty-six percent of those enrolled were deemed to be global responders.

Conclusions and relevance: Pioglitazone is well-tolerated and shows a potential signal in measures of social withdrawal, repetitive, and externalizing behaviors. Randomized controlled trials using the confirmed dose are warranted.

Trial registration: ClinicalTrials.gov, NCT01205282. Registration date: September 20, 2010.