Foundation for Angelman Syndrome Therapeutics Announces Agreement with Apertura Gene Therapy for Access to Blood-Brain Barrier-Crossing Capsid

— Agreement gives Foundation access to TfR1 CapX™ for Angelman syndrome gene therapy research and development programs —

AUSTIN, Texas and NEW YORK, Aug. 5, 2026 /PRNewswire/ -- The Foundation for Angelman Syndrome Therapeutics (FAST), the leading patient advocacy organization working to support the development of transformative treatment options for Angelman syndrome, today announced that it has entered into an agreement with Apertura Gene Therapy, a biotechnology company developing next-generation AAV capsids for delivering genetic medicines. Under the agreement, FAST may access TfR1 CapX™, Apertura's blood-brain barrier-crossing capsid technology, in investigational gene therapy programs designed for the treatment of Angelman syndrome.

Angelman syndrome is a rare, nondegenerative neurogenetic disorder that affects an estimated one in 15,000 people. It is caused by the loss of function of the UBE3A gene, which is critical for neuronal function. Angelman syndrome is associated with significant developmental delays, motor challenges, seizures, sleep disruption, and limited or no speech. Individuals living with Angelman syndrome require lifelong support. 

"Delivering potential genetic therapies to the central nervous system presents distinct scientific and delivery challenges for Angelman syndrome," said Julien de Bournet, Chief Business Officer of FAST. "Addressing those challenges requires exploring multiple scientific approaches and bringing together the right technologies and expertise. Our agreement for access to TfR1 CapX reflects FAST's commitment to investing in promising delivery technologies that could support future gene therapy programs."

TfR1 CapX is an AAV capsid designed to target human transferrin receptor 1 (hTfR1), cross the blood-brain barrier after intravenous administration, and enable broad distribution to the brain, addressing one of the major barriers to delivering therapeutics to the central nervous system. Several programs that use TfR1 CapX are expected to enter clinical trials over the next 12 months.

"This agreement between Apertura and FAST is an example of how biotech companies and patient advocacy organizations can collaborate to develop therapeutic programs that have the potential to help patients living with rare diseases," said Dave Greenwald, Ph.D., Executive Chairman of the Board at Apertura Gene Therapy and Managing Director at Deerfield Management.

About FAST (Foundation for Angelman Syndrome Therapeutics)

FAST is the leading patient advocacy organization working to cure Angelman syndrome. As the largest non-governmental funder of Angelman syndrome research in the world, our goal is to drive forward transformative research and development programs to have the greatest impact on those living with Angelman syndrome — regardless of age or genotype. Learn more at cureangelman.org and follow us on LinkedIn.

About TfR1 CapX™

TfR1 CapX™ is a leading IV-administered, BBB-crossing capsid. Multiple for-profit and non-profit organizations have validated and licensed TfR1 CapX, and other groups are in discussions to license the technology. Clinical readiness has been supported by several preclinical development programs, including regulatory engagement and manufacturing by contract development and manufacturing organizations (CDMOs). TfR1 CapX is a proprietary, second-generation capsid that demonstrates superior CNS delivery compared to Apertura's first-generation capsid, BI-hTFR1. Research on the first-generation BI-hTFR1 capsid was published in Science.

About Apertura Gene Therapy

Apertura Gene Therapy develops genetic medicines and next-generation AAV capsids that engage human-relevant receptors, aiming to enable more effective and selective gene delivery. The company's lead capsid, TfR1 CapX™, leverages human transferrin receptor 1 to enable intravenous delivery to the brain and spinal cord. This established transport mechanism has a strong clinical track record in pediatric and geriatric populations, expanding its potential to treat serious neurological and genetic diseases. Apertura has licensed its next-generation capsids to multiple partners, with several programs expected to enter clinical trials over the next 12 months. Founded in 2021 on technology from the Broad Institute and supported by Deerfield Management, Apertura Gene Therapy is headquartered in New York City. Learn more at aperturagtx.com and follow us on LinkedIn.

Contacts

For FAST
[email protected]

For Apertura Gene Therapy
[email protected]

SOURCE Apertura Gene Therapy