Seaside Therapeutics commences STX107 Phase 1 clinical trial for Fragile X Syndrome

Seaside Therapeutics LLC today announced that the Company has initiated a Phase 1 clinical trial of STX107, a highly potent, selective mGluR5 antagonist, in development for the treatment of Fragile X Syndrome. The single ascending dose study is designed to evaluate the safety, tolerability and pharmacokinetics of STX107 in healthy volunteers. Fragile X Syndrome is the most common inherited form of mental impairment and the most common known cause of autism.

“Individuals with Fragile X and other related brain development disorders need effective therapeutics directed towards the underlying disease pathophysiology, rather than just the associated symptomatic behaviors,” said Thomas R. Insel, M.D., Director of the National Institute of Mental Health. “The NIH is committed to funding groundbreaking basic scientific research to understand the etiology of Fragile X Syndrome with the ultimate goal of translating the resulting discoveries into novel therapeutics. Development of Seaside Therapeutics’ novel drug candidate, STX107, is representative of the promise of these efforts.”

Randall L. Carpenter, M.D., President and Chief Executive Officer of Seaside Therapeutics added, ”Initiation of the STX107 safety study is a momentous first step in the development of a potentially disease-modifying treatment for brain development disorders, such as Fragile X Syndrome and autism. Currently, there are no FDA approved drugs to enhance cognitive function for these disorders. We believe that normalizing signaling in the mGluR5 pathway with STX107 provides a compelling opportunity to correct or improve the course of Fragile X Syndrome, which could create a meaningful and lasting improvement in the lives of patients and their families.”

STX107 was selected for development based on the groundbreaking research of Seaside's scientific founder, Mark Bear, Ph.D., Howard Hughes Medical Institute Investigator and Picower Professor of Neuroscience at Massachusetts Institute of Technology. Dr. Bear discovered a connection between mGluR5 signaling and Fragile X Syndrome that suggests most, if not all, of the neurological and psychiatric consequences of Fragile X Syndrome can be accounted for by exaggerated signaling through mGluR5 receptors.

Based upon these insights, Seaside licensed and is developing a novel series of compounds targeting this receptor, including the lead compound STX107. Seaside has demonstrated that STX107 effectively normalizes function of the mGluR5 signaling pathway in genetically engineered animal models of Fragile X. This research played a critical role in the selection of STX107 for continued development and provides a further link between Dr. Bear’s insight into the biology of Fragile X Syndrome and small molecule antagonists of the mGluR5 receptor.


 Seaside Therapeutics


  1. Phil Gefsky Phil Gefsky United States says:

    My son Adam is 34 years old and is a diagnosed autistic and fragile x person. He is a very healthy person, who lives in an complex with special needs. Adam has a full time job as a janitor for the Air Force Reserve 911 Fighter Wing in Pgh. Pa. Adam has many of the developmental problems associated with Autism. Adam is very personable and easy and friendly. He has great family, work, and community relationships. We are very excited to hear about the recent Bears Drug stx107 research and how it may someday impcact on Adam's life.

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News Medical.
You might also like... ×
Taking lessons in molecular therapeutics from earthworms to combat COVID