Study of Arbaclofen for the Treatment of Social Withdrawal in Subjects With Autism Spectrum Disorders

A Randomized, Double-Blind, Placebo-Controlled Study of the Efficacy, Safety, and Tolerability of STX209 (Arbaclofen) Administered for the Treatment of Social Withdrawal in Subjects With Autism Spectrum Disorders

To explore the efficacy, safety and tolerability of STX209 (arbaclofen) administered for the treatment of social withdrawal in subjects with autism spectrum disorders

Inclusion Criteria:

• Diagnosis of Autism Spectrum Disorders (ASD)
• Current pharmacological treatment regimen has been stable for at least 4 weeks prior to Screening.
• Subjects with a history of seizure disorder must currently be receiving treatment with antiepileptics and must have been seizure free for 6 months, or must be seizure free for 3 years if not currently receiving antiepileptics.
• If the subject is already receiving stable non-pharmacologic educational, behavioral, and/or dietary interventions, participation in these programs must have been continuous during the 2 months prior to Screening

Exclusion Criteria:

• Subjects with any condition, including alcohol and drug abuse, which might interfere with the conduct of the study, confound interpretation of the study results, or endanger their own well-being.
• Subjects who plan to initiate or change pharmacologic or non-pharmacologic interventions during the course of the study.
• Subjects who have taken another investigational drug within the last 30 days.
• Subjects who are not able to take oral medications