GlobeNewswire·Nov 6, 2026, 3:30 AM ET

Ultragenyx Announces the Marketing Authorisation Application (MAA) for its Investigational Gene Therapy for MPS IIIA (Sanfilippo syndrome Type A) is Under Review with the UK Medicines and Healthcare Products Regulatory Agency (MHRA)

Ultragenyx announced that the UK MHRA accepted its Marketing Authorisation Application for rebisufligene etisparvovec (UX111) on October 28, 2026.
The investigational gene therapy targets Sanfilippo syndrome Type A, a rare progressive disorder causing severe neurological impairment with limited current treatment options.
MHRA acceptance confirms the application is complete to begin a formal scientific review, though no guarantee of eventual marketing authorisation is provided.
Ultragenyx plans to align the NICE evaluation timeline with the MHRA review to facilitate potential NHS funding decisions for eligible children.
The company previously announced the start of the European Medicines Agency (EMA) review process for the same application.
The NICE Prioritisation Board previously routed the treatment to the Highly Specialised Technology programme as it meets criteria for treating an ultra-rare condition.
Sanfilippo syndrome Type A is a fatal lysosomal storage disease caused by SGSH enzyme deficiency, affecting 3,000 to 5,000 patients with a median life expectancy of 15 years.
Rebisufligene etisparvovec is a single-dose intravenous AAV9 therapy designed to deliver a functional copy of the deficient enzyme gene.
The FDA granted approval for rebisufligene etisparvovec on September 17, 2026, though the product remains investigational in the UK.
Ultragenyx continues to pursue regulatory strategies in other geographies, including discussions with the Saudi Food and Drug Authority.