uniQure Huntington’s data show durable benefit, but 48-month controls muddy the read

uniQure is at the regulatory handoff for its Huntington’s gene therapy: the company submitted its BLA on September 2, 2026, after aligning with the FDA on an accelerated-approval path, while the confirmatory study remains the route to full approval.

The expanded 36-month dataset strengthens the regulatory story. Adding three high-dose patients produced 80% slowing on cUHDRS and 67% on TFC, the functional measure that anchors the confirmatory study. 〔0〕 This is better than merely preserving the prior signal: it gives the already-submitted BLA a larger supporting dataset, although the new results were not included in that submission.

The four-year read is directionally encouraging but statistically uneven. At 48 months, TFC showed a nominally significant 61% slowing, while the prespecified cUHDRS endpoint showed 44% slowing that was not statistically significant. 〔1〕 The apparent persistence of functional benefit is useful evidence for durability, but it is not a clean confirmation across both measures.

The external-control comparison is the main qualification. Missing data reached 53% in the updated matched controls at 48 months, and faster-progressing patients were more likely to disappear from follow-up. 〔2〕 Using an earlier control dataset improved the reported 48-month effect, but that sensitivity also shows how dependent the long-term percentages are on comparator construction. The 36-month result is therefore the cleaner regulatory signal; the 48-month result is supportive, not definitive.

Safety remains manageable but not immaterial. The company says the procedure-related adverse events resolved, while five high-dose participants, or 17%, experienced treatment-related serious events involving central nervous system inflammation, all of which resolved. 〔3〕 That does not overturn the efficacy read, but it remains part of the approval and confirmatory-study burden.

Bottom line: This update clears the practical bar for a stronger BLA narrative: the expanded three-year data are robust and the benefit appears to persist functionally into year four. The result is meaningfully supportive, but the non-significant four-year primary endpoint and fragile external control keep it from being a clean, conclusive validation of durability.