UniQure (QURE) said Tuesday additional data from its ongoing phase 1/2 studies of AMT-130 in Huntington's disease showed less pronounced benefits at 48 months.

The company said the primary endpoint of composite Unified Huntington's Disease Rating Scale showed 44% slowing of disease progression in 12 high-dose patients at 48 months, lower than the updated 36-month data of 80% slowing of disease progression in 15 high-dose patients.

Total functional capacity delivered a 61% slowing of disease progression in 12 high-dose patients at 48 months, compared with the updated 36-month data of 67%, the company said.

The company's shares fell 52.5% in premarket activity Tuesday.