Adjunctive Intra-arterial Urokinase after Successful Endovascular Thrombectomy in Patients with Large Vessel Occlusion Stroke (POST-UK): Study protocol of a multicenter, prospective, randomized, open-label, blinded-endpoint trial

Background: Intra-arterial infusion of an adjunctive thrombolytic agent after macrovascular recanalization by endovascular thrombectomy (EVT) was regarded as a promising strategy to promote outcomes of stroke patients. Given the characteristics of urokinase (UK) as an affordable, available, and widely applied medication, especially in eastern countries, this trial aims to assess the safety and efficacy of intra-arterial UK as adjunct to EVT in improving outcomes among patients with anterior large vessel occlusion stroke after excellent to complete reperfusion. Methods: The Adjunctive Intra-arterial Urokinase after Successful Endovascular Thrombectomy in Patients with Large Vessel Occlusion Stroke (POST-UK) trial is a multicenter, prospective, randomized, open-label, blinded-endpoint trial conducted in China. The planned sample size is 498. Those eligible patients with anterior circulation large vessel occlusion stroke and achieving excellent to complete reperfusion by EVT are planned to be consecutively randomized in a 1:1 ratio to the experimental group (a single dose of intra-arterial urokinase) or to standard of care. Results: The primary outcome is a freedom from disability (modified Rankin Scale, mRS, of 0-1) at 90±7 days. The safety outcomes are mortality within 90±7 days and symptomatic intracranial hemorrhage within 48 hours. Conclusions: The POST-UK trial will provide valuable insight of efficacy and safety of intra-arterial UK in patients with large vessel occlusion stroke after achieving excellent to complete reperfusion by EVT.