Hyperactivity, impulsiveness, and distractibility are common problems in children with autism spectrum disorder (ASD). Extended-release guanfacine is approved for children with attention deficit hyperactivity disorder but not well studied in ASD.In a multisite, randomized clinical trial, extended-release guanfacine was compared with placebo in children with ASD accompanied by hyperactivity, impulsiveness, and distractibility.Sixty-two subjects (boys, N=53; girls, N=9; mean age=8.5 years [SD=2.25]) were randomly assigned to guanfacine (N=30) or placebo (N=32) for 8 weeks. The guanfacine group showed a 43.6% decline in scores on the Aberrant Behavior Checklist-hyperactivity subscale (least squares mean from 34.2 to 19.3) compared with a 13.2% decrease in the placebo group (least squares mean from 34.2 to 29.7; effect size=1.67). The rate of positive response (much improved or very much improved on the Clinical Global Impression-Improvement scale) was 50% (15 of 30) for guanfacine compared with 9.4% (3 of 32) for placebo. A brief cognitive battery tapping working memory and motor planning showed no group differences before or after 8 weeks of treatment. The modal dose of guanfacine at week 8 was 3 mg/day (range: 1-4 mg/day), and the modal dose was 3 mg/day (range: 2-4 mg/day) for placebo. Four guanfacine-treated subjects (13.3%) and four placebo subjects (12.5%) exited the study before week 8. The most common adverse events included drowsiness, fatigue, and decreased appetite. There were no significant changes on ECG in either group. For subjects in the guanfacine group, blood pressure declined in the first 4 weeks, with return nearly to baseline by endpoint (week 8). Pulse rate showed a similar pattern but remained lower than baseline at endpoint.Extended-release guanfacine appears to be safe and effective for reducing hyperactivity, impulsiveness, and distractibility in children with ASD.

Background

Experimental studies and small clinical trials have suggested that treatment with intranasal oxytocin may reduce social impairment in persons with autism spectrum disorder. Oxytocin has been administered in clinical practice to many children with autism spectrum disorder.

Methods

We conducted a 24-week, placebo-controlled phase 2 trial of intranasal oxytocin therapy in children and adolescents 3 to 17 years of age with autism spectrum disorder. Participants were randomly assigned in a 1:1 ratio, with stratification according to age and verbal fluency, to receive oxytocin or placebo, administered intranasally, with a total target dose of 48 international units daily. The primary outcome was the least-squares mean change from baseline on the Aberrant Behavior Checklist modified Social Withdrawal subscale (ABC-mSW), which includes 13 items (scores range from 0 to 39, with higher scores indicating less social interaction). Secondary outcomes included two additional measures of social function and an abbreviated measure of IQ.

Results

Of the 355 children and adolescents who underwent screening, 290 were enrolled. A total of 146 participants were assigned to the oxytocin group and 144 to the placebo group; 139 and 138 participants, respectively, completed both the baseline and at least one postbaseline ABC-mSW assessments and were included in the modified intention-to-treat analyses. The least-squares mean change from baseline in the ABC-mSW score (primary outcome) was -3.7 in the oxytocin group and -3.5 in the placebo group (least-squares mean difference, -0.2; 95% confidence interval, -1.5 to 1.0; P = 0.61). Secondary outcomes generally did not differ between the trial groups. The incidence and severity of adverse events were similar in the two groups.

Conclusions

This placebo-controlled trial of intranasal oxytocin therapy in children and adolescents with autism spectrum disorder showed no significant between-group differences in the least-squares mean change from baseline on measures of social or cognitive functioning over a period of 24 weeks. (Funded by the National Institute of Child Health and Human Development; SOARS-B ClinicalTrials.gov number, NCT01944046.).