Double-Blind, Placebo-Controlled Trial of D Cycloserine Given Prior to Peer Mediated Social Skills Training in Youth with an Autism Spectrum Disorder: Initial Findings

Background:  No drugs are FDA approved for use targeting the core social impairment of autism and related pervasive developmental disorders (PDDs). Glutamatergic dysregulation is implicated in the pathophysiology of PDDs, now termed ASD. D-Cycloserine (DCS) is FDA approved for the treatment of tuberculosis and the drug is known to impact NMDA glutamate receptor neurotransmission. DCS has been shown to potentiate learning when given prior to therapy sessions in the anxiety disorder literature.

Objectives:  We evaluated the efficacy of DCS given 30 minutes prior to peer mediated social skills training (SST) in youth aged 5 to 11 years with ASD.

Methods:  We conducted a double-blind, placebo-controlled trial of low dose (50mg) DCS given prior to manualized SST in 68 children aged 5 to 11 years with ASD over 10 weekly sessions. SST sessions each included 4 youth with ASD and 2 age-matched typically developing peers trainers along with two clinician group facilitators.  In addition to evaluating primary and secondary outcome measures after 10 weeks of SST, we additionally conducted a follow up evaluation for each participants 3 months following the SST. Participants with ASD were required to have a full scale IQ greater than 70, meet DSM IV-TR criteria for autistic disorder, Asperger's disorder, or pervasive developmental disorder not otherwise specified (PDD-NOS) based upon clinical interview and results from the Autism Diagnostic Interview Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS). Our primary outcome measure was the total score on the Social Responsiveness Scale (SRS). Key secondary outcome measures included the Clinical Global Impresisons Improvement (CGI-I) and Severity (CGI-S) scales, the Aberrant Behavior Checklist (ABC), Pediatric Quality of Life Inventory, 4th Edition, and the Vineland-II. We additionally compiled structure observational behavioral data coding with each session to track potential change with treatment throughout the SST.

Results:  Sixty-eight youth were enrolled in this trial. The results will be available in Spring 2014. Top line results reviewing the primary and key secondary outcome measures will be reported for the drug versus placebo groups in May 2014.

Conclusions: Preliminary conclusions will be generated following the dissemination of top line results in May 2014.