UniQure shares plunge after Huntington's therapy fails trial

UniQure shares fell 37 to 40 percent on September 29, 2026, after the company released four-year Phase 1/2 data on its Huntington's gene therapy AMT-130. In 12 high-dose patients, disease progression slowed 44% on the cUHDRS scale at 48 months versus an updated external control, a result that was not statistically significant (p=0.144). Slowing on the TFC scale was 61%. UniQure said the results show a "meaningful" effect and that missing data in the control likely understated the treatment effect; a post-hoc analysis using prior external control showed 54% and 68% slowing. Updated three-year results from 15 patients showed 80% slowing on cUHDRS and 67% on TFC. UniQure submitted applications to the FDA and UK MHRA in early September 2026 after the FDA reversed a November rejection and agreed in June 2026 to accept the Phase 1/2 data for accelerated approval review. Leerink analysts wrote AMT-130 is "clearly doing something" and making patients wait for a Phase 3 trial "seems inappropriate." Stifel's Paul Matteis called four-year results "still impressive generally" despite "some regression," and said three-year data "look robust" and "are arguably most important."