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Seaside Therapeutics Presents Data on Potential Pharmaceutical Treatment for Improving Social Impairment in Autism Spectrum Disorders at 42nd Autism Society National Conference

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Jul 8, 2011 - Seaside Therapeutics announced that data on its clinical candidate, STX209, was presented today in an oral presentation at the 42nd Autism Society National Conference in Orlando, FL, by Barbara Rathmell, M.D., Senior Medical Director at Seaside Therapeutics. The talk, titled “Potential Pharmaceutical Treatments for Improving Social Function in ASD,” described positive data from an open-label Phase 2a study of STX209 conducted in patients with autism spectrum disorders (ASD). STX209 is a selective gamma-amino butyric acid type B (GABA-B) receptor agonist being studied for the treatment of ASD and fragile X syndrome (FXS).

As previously reported, STX209 demonstrated statistically significant improvements across a number of global and specific neurobehavioral outcomes in the open-label Phase 2a study, including significant improvements in social impairment—a core symptom of ASD. Social impairment includes symptoms such as preference to be alone, being withdrawn or isolated and lack of social reactivity. Additionally, STX209 was found to be well-tolerated. A significant number of patients enrolled in the study continue to participate in an open-label extension study.

In June 2011, the Company announced the initiation of a randomized, double-blind, placebo-controlled Phase 2b study to evaluate the effects of STX209 on social impairment in children, adolescents and adults (ages 5 to 21) with ASD. Subjects who complete the entire 12-week study may be eligible to enroll in a subsequent open-label study. The Phase 2b study will involve approximately 25 clinical sites in the United States and enroll 150 subjects. The study is currently enrolling patients at a number of clinical trial sites across the United States. Details of the study and a list of participating clinical trial sites can be obtained at and at or by calling 1-877-713-9009, option 8.

About STX209:

STX209 is an oral selective gamma-amino butyric acid type B (GABA-B) receptor agonist. Pathologies observed in certain neurodevelopmental disorders, including autism spectrum disorders (ASD) and fragile X syndrome (FXS), 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. STX209 has demonstrated efficacy in preclinical models, suggesting that it may improve function in individuals with ASD and FXS.

With STX209, Seaside has successfully completed the largest, randomized, blinded, placebo-controlled trial (Phase 2) in patients with FXS and an open-label Phase 2a exploratory trial in patients with ASD. A Phase 3 study in adolescents and adults (ages 12 to 25) with FXS began in May of 2011 and a Phase 2b study in children, adolescents and adults (ages 5 to 21) with ASD began in June of 2011. An additional Phase 3 study in children (ages 5 to 11) with FXS is expected to begin in early summer 2011.

About Autism Spectrum Disorders:

Autism Spectrum Disorders (ASD) are characterized by three hallmark symptoms that can range from mild to disabling, including difficulties with social interaction, problems with verbal and nonverbal communication and repetitive behaviors or narrow, obsessive interests. Experts estimate that as many as 1 in 110 children are diagnosed with an autism spectrum disorder, with boys being four times more likely than girls to be diagnosed with the disorder. There is no cure for autism and there are currently no FDA approved therapeutics to treat the core symptoms of ASD.

About Seaside Therapeutics:

Seaside Therapeutics, Inc. is creating novel drug treatments to correct or improve the course of fragile X syndrome, autism and other neurodevelopmental disorders. The Company is dedicated to translating breakthrough discoveries in neurobiology into therapeutics that improve the lives of patients and their families. For more information please visit


Contact: MacDougall Biomedical Communications
Sarah Cavanaugh, 781-235-3060
Kari Watson, 781-235-3060


Posted: July 2011