Spinogenix and FRAXA Advance SPG601 Into Phase 2b Trial for Fragile X Syndrome
Spinogenix Announces FRAXA Research Foundation Support for PIs Leading Phase 2b Trial of Investigational Therapy SPG601 for People with Fragile X Syndrome (FXS)
SPG601 is a first-in-class, BK-modulator with the potential to improve cognitive, emotional and sensory symptoms in FXS patients.
LOS ANGELES, February 28, 2026 — Spinogenix, Inc., a clinical-stage biopharmaceutical company pioneering first-in-class therapeutics with the potential to restore synapses that could improve the lives of patients worldwide, today announced that a grant from the FRAXA Research Foundation will support the site principal investigators (PIs) in the Phase 2b trial of SPG601, a first-in-class treatment for Fragile X syndrome (FXS), assessing its safety and efficacy in patients with FXS. The planned Phase 2b adaptive trial design will allow a seamless transition into a Phase 3 trial.
FRAXA’s early preclinical support helped establish the calcium-activated potassium (“BK”) channel modulator mechanism behind SPG601. FRAXA also supported the development of another BK channel modulator, KER-0193, which released Phase 1 results last year and was acquired by Servier from Kaerus for $450M in September 2025.
“We have long believed that a mechanism targeting BK channels could make a significant difference to the lives of patients with Fragile X syndrome and their loved ones, and have consistently supported its development,” said Michael Tranfaglia, MD, Co-founder of the FRAXA Research Foundation. “I was delighted to see our belief in SPG601 come to fruition with the Phase 2a trial providing the first evidence of efficacy in patients with FXS. We are thrilled to partner with the principal investigators working with Spinogenix to advance this BK channel opener in a larger registrational-directed study.”
SPG601 works at the synaptic level, targeting a well-established molecular dysfunction in FXS, to improve core symptoms and challenging behaviors, which can include severe anxiety, social aversion, hyperactivity and attention deficit. It is a small molecule that targets large-conductance BK channels, increasing their activation to correct specific synaptic dysfunctions that are thought to underlie many core symptoms of FXS.
“After years of evaluating investigational therapies in FXS, it is rare to see results this compelling and it is gratifying to see our collaboration with FRAXA continue as we advance SPG601,” said Dr. Craig Erickson, PI of the planned Phase 2b trial, Director of the Cincinnati Fragile X Research and Treatment Center and Spinogenix Chief Medical Advisor. "The Phase 2a findings are among the most remarkable observed in FXS to date, and the effects on gamma band activity, as seen in EEG recordings, along with correlated improvements in measures of attention and inhibitory control, highlight the promise of SPG601."
SPG601 is on an expedited path to regulatory approval, having received Fast Track Designation and Orphan Drug Designation by the FDA, as well as Orphan Disease Designation by the EMA.
“We are thrilled to have the support of FRAXA as part of our journey to develop a treatment for this rare and debilitating genetic disorder where there are currently no FDA-approved treatments,” said Dr. Stella Sarraf, Chief Executive Officer and Founder of Spinogenix. “FXS not only impacts the individual but entire families, both economically and emotionally. My hope is that we are able to improve the quality of life of the patient and change their trajectory in life and this next trial allows us to get one step closer to that vision.”
About SPG601
SPG601 is an oral investigational medication being developed to treat FXS, and potentially other conditions on the autism spectrum, by mitigating key underlying abnormalities in synaptic function and neural excitability. FXS involves a reduction in the activity of large conductance, calcium-activated potassium (BK) channels, which contributes to synaptic dysfunction, cortical hyperexcitability, and multiple symptoms of FXS. SPG601, a novel small molecule, is the first positive modulator of BK channels to be clinically evaluated in FXS patients in a Phase 2a study and demonstrated the potential to improve cognitive, emotional, and sensory symptoms by boosting BK channel activity. SPG601 has received both Orphan Drug designation and Fast Track designation from the FDA for FXS, as well as orphan disease designation from the EMA. Plans for a registrational-directed Phase 2b/3 trial have been agreed to with the FDA.
About Fragile X Syndrome
Fragile X Syndrome (FXS) is the leading inherited form of intellectual disability and a known cause of autism that results from the silencing of the Fmr1 gene. FXS is an orphan disease affecting approximately 1 in 4-5000 men and 1 in 6-8000 women globally. In addition to intellectual disability, FXS patients endure a wide range of disabling symptoms, including severe anxiety, social aversion, hyperactivity and attention deficit, sensory hypersensitivity, aggression, developmental seizures, and others. Providing care for individuals with FXS often becomes a full-time commitment for at least one parent and imposes significant financial strain, with direct family healthcare costs totaling $4.1 billion annually in the United States alone. Despite the considerable impact of FXS, there are currently no FDA-approved drugs available for those with the condition.
About FRAXA
FRAXA Research Foundation is a national nonprofit organization founded in 1994 by parents to find effective treatments and ultimately a cure for Fragile X syndrome. FRAXA has funded over $38.5 million in research grants and fellowships at top universities around the world and partners with biotech and pharmaceutical companies to bridge the gap between research discoveries and actual treatments.