Abstract Body: Background and Aims: Endovascular treatment (EVT) alone has been confirmed to be non-inferior to intravenous thrombolysis (IVT) followed with EVT in acute ischemic stroke (AIS) due to large-vessel occlusion of the anterior circulation. This trial aims to investigate the efficacy and safety of EVT with or without IVT in AIS due to basilar artery occlusion (BAO).
Methods and Design: The BEST-BAO trial is an investigator-initiated, multicenter, prospective, randomized controlled design. Three hundred and forty eligible patients from planned 115 stroke centers in China with AIS of BAO within 4.5 hours after symptom onset will be randomly assigned in a 1:1 ratio to undergo EVT alone (EVT group) or EVT preceded by IVT (IVT+EVT group; intravenous alteplase, 0.9 mg/kg of body weight, 10% administered as a bolus, followed by a 1-hour infusion of the remaining dose). EVT consists of mechanical thrombectomy, thromboaspiration, balloon dilation, stenting, intra-arterial thrombolysis, or various combinations of these methods. The selection of techniques is left to the discretion of the treating neurointerventionist.
Outcomes: The primary outcome is the proportion of a good functional status, which is defined as a modified Rankin Scale (mRS) score of 0 to 2 on day 90 after stroke onset. Secondary outcomes include, but are not limited to, the distribution across mRS score categories on day 90, the proportion of patients with an mRS score of 0 to 3 on day 90, the proportion of successful reperfusion on end-of-procedure catheter angiography (modified thrombolysis in cerebral infarction 2b to 3), and vessel revascularization determined by CTA, DSA, or MRA within 24 to 72 hours. Safety outcomes include, but are not limited to, all-cause mortality within 90 days, symptomatic intracranial hemorrhage within 72 hours, and severe adverse events within 90 days.
Discussion: The BEST-BAO trial may redefine current clinical approaches by determining whether EVT alone is sufficient or if adding IVT confers additional benefits. While EVT alone has been shown to be beneficial in anterior circulation strokes, AIS due to BAO requires a focused investigation owing to unique pathophysiological characteristics.
Trial registration: NCT05631847 (ClinicalTrials.gov) and ChiCTR2300070584 (Chinese Clinical Trial Registry, https://www.chictr.org.cn).