UX111 (rebisufligene etisparvovec)
Sanfilippo syndrome type A (mucopolysaccharidosis type IIIA) · Patients with Sanfilippo syndrome type A
RARE · Ultragenyx Pharmaceutical
Regulatory designations
Full timeline
4 milestonesFDA decision expected
FDA assigned a September 19, 2026 PDUFA action date to the resubmitted BLA seeking accelerated approval for UX111.
Ultragenyx — BLA resubmission acceptance and PDUFA date↗FDA accepted the BLA resubmission
FDA accepted the resubmitted UX111 BLA for review after Ultragenyx added information addressing the prior manufacturing-related observations.
Ultragenyx — BLA resubmission acceptance↗FDA issued a Complete Response Letter in the first review cycle
The CRL cited chemistry, manufacturing and controls observations; Ultragenyx said FDA acknowledged the clinical data as robust and the biomarker evidence as supportive.
Ultragenyx — UX111 Complete Response Letter↗Ultragenyx submitted the original BLA
Ultragenyx submitted the original BLA seeking accelerated approval, supported by data from the ongoing Transpher A study.
Ultragenyx — 2024 results and UX111 regulatory update↗Related News
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