Ifezuntirgene inilparvovec enters regulatory review under the Accelerated Approval pathway, supported by Phase I/II clinical data and a planned confirmatory study.
Written By: Creola Gonsalves, MS, Biotech
Reviewed By: Pharmacally Editorial Team
uniQure N.V. has received U.S. Food and Drug Administration (FDA) acceptance of its Biologics License Application (BLA) for ifezuntirgene inilparvovec (AMT-130), an investigational gene therapy for Huntington’s disease. The application has been granted Priority Review under the Accelerated Approval pathway, with a Prescription Drug User Fee Act (PDUFA) target action date of May 1, 2027.
The FDA has also indicated that it is tentatively planning to discuss the application at an Advisory Committee meeting, although the date has not been finalized. If approved, AMT-130 could become the first disease-modifying treatment for Huntington’s disease.
Clinical Evidence Supporting the Application
The BLA is supported by the previously reported 36-month analysis from uniQure’s Phase I/II clinical programme, which compared treated patients with propensity score-matched external controls derived from the Enroll-HD natural history database.
In the September 2025 analysis, the high-dose group demonstrated 75% relative slowing of disease progression on the composite Unified Huntington’s Disease Rating Scale (cUHDRS), the primary endpoint (p=0.003). The key secondary endpoint, Total Functional Capacity (TFC), showed 60% relative slowing (p=0.033).
An expanded analysis announced in September 2026 reported 80% slowing on cUHDRS and 67% on TFC at 36 months in the high-dose group. However, these additional results were announced after BLA submission and were not included in the application. The original 36-month dataset remains the basis of the regulatory submission.
The clinical comparisons rely on external natural-history controls rather than a contemporaneous randomized control group. Further confirmatory evidence will therefore be important in establishing clinical benefit.
Regulatory Background and Confirmatory Trial
AMT-130’s regulatory progression follows earlier FDA concerns about whether Phase I/II data using an external control could provide sufficient primary evidence for a BLA. In late 2025 and early 2026, the agency questioned the adequacy of this evidence and recommended a prospective randomized, sham surgery-controlled study.
Following a Type B meeting in June 2026, the FDA and uniQure reached alignment that the existing 36-month clinical data could support a BLA submission under the Accelerated Approval pathway.
The company and FDA have also aligned on key elements of a confirmatory study involving approximately 200 patients randomized in a 2:1 ratio to AMT-130 or standard of care. TFC will serve as the primary endpoint at 36 months. Patient screening in the United States is expected to begin by the end of 2026.
Drug Profile and Clinical Significance
AMT-130 uses uniQure’s proprietary miQURE gene-silencing platform, incorporating microRNA (miRNA) technology designed to reduce huntingtin gene expression and the potentially toxic huntingtin exon 1 protein fragment.
The therapy is administered once through MRI-guided, convection-enhanced stereotactic neurosurgery, delivering the treatment directly into the striatum, including the caudate and putamen.
Huntington’s disease is an inherited, progressive neurodegenerative disorder caused by mutations in the HTT gene. It affects motor function, cognition and behaviour. Currently, no approved treatment delays or slows the underlying progression of the disease.
Regulatory Outlook
The FDA’s acceptance of the BLA marks an important milestone for uniQure following earlier uncertainty surrounding the sufficiency of its clinical evidence. Priority Review establishes an expedited regulatory timeline, but acceptance does not guarantee approval.
The May 1, 2027 PDUFA date and progress of the confirmatory study will be important milestones in determining AMT-130’s potential role in Huntington’s disease treatment.
Reference
uniQure Announces FDA Acceptance and Priority Review of the Biologics License Application for ifezuntirgene inilparvovec for the Treatment of Huntington’s Disease, uniQure, 02 November 2026
About the Writer
Creola Gonsalves (Linkedin) is an M.S. Biotechnology postgraduate with a strong interest in clinical research, evidence interpretation, and healthcare writing, with a focus on translating life-science knowledge into meaningful real-world insights.
She is trained in Good Clinical Practice (GCP), clinical research principles, and critical interpretation of randomized clinical trials, with certifications from NIH and Stanford University.
Her research background in biotechnological applications and microbial research strengthens her ability to understand scientific evidence and develop clear, accurate, and research-driven healthcare content.