UniQure N.V. (NASDAQ: QURE) stock fell 55.6% in pre-market trading on September 29, 2026, after the company's experimental gene therapy for Huntington's disease failed to meet the primary endpoint in a Phase I/II clinical trial.
What happened
UniQure announced additional data from the ongoing Phase I/II studies of ifezuntirgene inilparvovec (AMT-130) in Huntington's disease on September 29, 2026. Reuters reported that the therapy failed to significantly slow disease progression in the trial, marking a significant setback for the company's lead neurological program.
Why the stock moved
The clinical readout from Reuters on September 29 at 11:36 AM ET revealed that AMT-130 did not achieve its primary endpoint of demonstrating statistically significant slowing of disease progression in Huntington's patients. Huntington's disease is a fatal genetic disorder with no cure, and investors had placed substantial value on the therapy's potential approval following the company's earlier Biologics License Application submission. The failure to meet the primary endpoint undermines the therapy's path to regulatory approval and dramatically reduces its commercial potential, triggering the sharp sell-off.
The numbers
QURE opened the pre-market session at $17.39, down from the previous regular close of $39.13, representing a 55.55% decline. Volume in the session reached 4,990,571 shares, more than four times the stock's average daily volume of approximately 1.2 million shares. The company's market capitalization fell from roughly $2.4 billion to approximately $1.1 billion based on the new price level.
What to watch
Investors will monitor for any additional commentary from uniQure management regarding the trial results and whether the company plans to pursue further development of AMT-130 based on secondary endpoints or subgroup analyses. The company's Huntington's program had been under FDA review following the BLA submission in September 2026, and the failure to meet the primary endpoint could complicate or delay that regulatory process. UniQure's other pipeline programs, including its hemophilia B therapy Etranacogene dezaparvovec, remain key to the company's valuation.