The Foundation for Angelman Syndrome Therapeutics (FAST) has entered an agreement with New York-based Apertura Gene Therapy to access TfR1 CapX, a next-generation adeno-associated virus (AAV) capsid designed to cross the blood-brain barrier (BBB) after intravenous administration, for use in Angelman syndrome gene therapy research and development programs. Financial terms were not disclosed.
TfR1 CapX is described by Apertura as targeting human transferrin receptor 1 (hTfR1) to enable receptor-mediated transport across the BBB, allowing broad distribution to the brain and spinal cord following systemic delivery. Apertura, which was founded in 2021 on technology from the Broad Institute and is backed by Deerfield Management, says research on the earlier BI-hTFR1 capsid was published in Science, and that multiple programs using TfR1 CapX are expected to enter clinical trials within the next 12 months.
The deal is structured as a non-exclusive access license, consistent with Apertura's broader platform-licensing model. The company has executed a series of TfR1 CapX agreements across 2025 and 2026, including licenses to Galibra Neuroscience and Emugen Therapeutics, a platform combination deal with AviadoBio, and a cooperative research and development agreement with the National Institutes of Health for Niemann-Pick Disease Type C1.
FAST operates as a nonprofit foundation, funding preclinical research, then licensing assets into dedicated portfolio companies under its AS2Bio accelerator vehicle establised in June 2024.