EXtending the tIme Window of Thrombolysis by ButyphThalide up to 6 Hours After Onset (EXIT-BT)

To date, the time window of intravenous thrombolysis is limited within 4.5 hours of stroke onset. Although EXTEND study has proved that intravenous thrombolysis can be extended from 4.5 to 9 hours, but the eligible patients must be selected by CTP. Thus, it is of clinical importance how to extend the time window of intravenous thrombolysis, which can benifit more patients. The current trial aims to investigate the effect of intravenous thrombolysis with TNK from 4.5 to 6 hours in ischemic stroke with help of Butyphthalide, which was found to be neuroprotective.