MavriX Bio, a clinical-stage biotechnology company, announced on Monday that it has received Fast Track designation from the US Food and Drug Administration (FDA) for MVX-220, an investigational adeno-associated virus (AAV) gene therapy for the treatment of Angelman syndrome (AS).

The company is preparing to start ASCEND-AS, a Phase 1/2 first-in-human study of MVX-220 in AS.

MavriX Bio is joining the Foundation for Angelman Syndrome Therapeutics (FAST) and the Angelman Syndrome Foundation (ASF) for an Angelman Community Webinar on Thursday, 9 October 2025 to provide a summary of the trial design, enrolment criteria and study procedures for the ASCEND-AS study.

James M. Wilson, MD, PhD, CEO of GEMMA Biotherapeutics (GEMMABio), whose team developed MVX-220, said: "GEMMABio has been deeply honoured to support MavriX Bio on the MVX-220 development programme. With Fast Track status, this programme gains crucial momentum -- it means the team can engage more closely with regulators and accelerate development milestones. For the Angelman syndrome community, Fast Track designation opens up a path toward bringing gene-targeted therapies to patients sooner."