its drug improves aberrant behaviors, such as extreme social anxiety that often causes children with the disease to spend hours alone in their rooms instead of interacting with friends and family.
STX209 stimulates receptors in the brain called GABA-B, which play a key role in modulating excitatory and inhibitory signals. “In both fragile X and autism, there’s too much excitation and not enough inhibition,” Carpenter explains. “We can get that back into balance.”
Results from early trials have been promising, Carpenter says. “The children on the drug are less likely to spend all their time in solitary play,” he says. “They’re now interacting much more with their siblings, parents, and friends. For parents, this is really important, because that’s the main thing they worry about. Does my child have friends? Are they willing to play with their siblings? Do they like me? We’re getting really encouraging reports.”
The second class of drugs that Seaside is working on with Roche—mGluR5 antagonists—also target brain signaling, but in a different way. Patients with fragile X have a genetic abnormality that disrupts a particular protein in the brain involved in learning and memory. Inhibiting mGluR5 seems to restore the proper balance of that protein. “It allows the brain to determine more effectively what’s important information and what’s noise,” Carpenter says. “That allows it to learn better from experience.”
Seaside has an unusual list of investors that reside outside of the venture capital world, and therefore are more interested in finding cures for brain disorders than they are in making money, Carpenter says. Since the company was founded in 2005, it has raised more than $66 million from a private family investment fund and organizations such as the Fragile X Research Foundation, Autism Speaks, and the National Institutes of Health. “Because our investors have been focused on the societal returns and not the financial returns, it has allowed us to be more openly collaborative than is possible in a venture-backed or public company,” Carpenter says.
Roche and Seaside have crossed paths at several venues, including the Banbury Meeting, an annual gathering at Cold Spring Harbor Laboratory in New York, where researchers trade notes on fragile X research. And earlier this year, Carpenter spoke at a symposium on autism hosted by Roche.
Carpenter says Seaside will benefit from Roche’s worldwide leadership in neurology research. Roche is one of seven major pharmaceutical companies leading a $38.7 million initiative to bring academic scientists and industry together for autism research, for example. It is also leading the effort to search for biomarkers—molecular signatures that may contribute to developmental disorders and serve as targets for new drugs. “We’re comfortable we share the same mission and have the same passion,” Carpenter says. “I think they’re an ideal partner for us.”
