CAMBRIDGE, MA, USA I May 1, 2013 I Seaside Therapeutics announces that the results of its Phase 2b trial evaluating arbaclofen (STX209) to treat core impairments of autism spectrum disorder (ASD) will be presented tomorrow, May 2, 2013, at the International Meeting for Autism Research (IMFAR), in San Sebastian/Donostia, Spain. Jeremy Veenstra-Vanderweele, M.D., Associate Professor of Psychiatry, Pediatrics, and Pharmacology at Vanderbilt University and a key investigator in the study, will present the data.

Study 209AS208, a randomized, double-blind, placebo-controlled Phase 2b study, evaluated the safety, tolerability, and efficacy of arbaclofen in 150 subjects (age 5 to 21 years) with ASD, with a particular focus on the core impairments of social function. Patients were randomized to receive either arbaclofen or placebo and treated for 12 weeks. While the study did not show improvement on the primary endpoint of social withdrawal, it did demonstrate significant improvement on the Clinical Global Impression of Severity scale. Secondary analyses of the data revealed significant improvement on the Vineland-II Socialization scale, a gold-standard psycho-educational measure of social function, in higher functioning patients.

“There currently are no FDA-approved therapeutics to treat the core impairments of ASD. These data represent an important advance towards addressing this serious unmet medical need,” said Paul Wang, M.D., Vice President for Clinical and Medical Affairs, Seaside Therapeutics. “ASD is a heterogeneous disorder, in terms of its etiology and its clinical presentation. This study helps us better understand which patients with ASD respond most readily to treatment with arbaclofen.”

Seaside intends to confirm its results by initiating another controlled trial of arbaclofen in patients with ASD.

About Arbaclofen:

Arbaclofen (STX209) is an oral, selective, gamma-aminobutyric acid type B (GABA-B) receptor agonist. Pathologies observed in certain neurodevelopmental disorders, including autism spectrum disorder and fragile X syndrome, are believed to be caused by excessive activation of glutamate receptors and abnormally high ratios of excitatory to inhibitory neurotransmission in the brain. GABA-B receptors play an important role in modulating the release of glutamate and optimizing the ratio of excitatory to inhibitory neurotransmission. Arbaclofen has demonstrated efficacy in preclinical models, suggesting that it may improve function in individuals with autism spectrum disorder and fragile X syndrome. With arbaclofen, Seaside has successfully completed the largest, randomized, blinded, placebo-controlled trial (Phase 2) in patients with fragile X syndrome, an open-label Phase 2a exploratory trial in patients with autism spectrum disorder and a Phase 2b randomized, double-blinded, placebo-controlled trial in subjects (ages 5 to 21) with autism spectrum disorder. Two Phase 3 studies in fragile X syndrome, one in adolescents and adults (ages 12 to 50) and one in children (ages 5 to 11), are fully enrolled and results are expected in 2013.

About Autism:

Autism is a general term used to describe a group of complex developmental brain disorders – autism spectrum disorders (ASD) – caused by a combination of genetic and environmental factors. These disorders are characterized, in varying degrees, by social and communication difficulties and by restricted and repetitive behaviors. According to recent estimates from the Centers for Disease Control and Prevention, as many as 1 in 50 children in the U.S. are on the autism spectrum.

About Seaside Therapeutics:

Seaside Therapeutics was founded to deliver medications that fundamentally alter the course of autism and intellectual disability. Through our research on single gene disorders that are associated with these conditions, we are developing targeted treatments that address the core impairments of autism and intellectual disability, with the goal of improving quality of life for affected persons and their families. www.seasidetherapeutics.com

SOURCE: Seaside Therapeutics