Endovascular Acute Stroke Intervention - Tandem OCclusion Trial

EASI-TOC is a phase III multi-centre, prospective, randomized, open-label, blinded endpoint (PROBE) controlled trial (1:1 allocation). The trial will seek to determine if in patients undergoing acute intracranial thrombectomy for anterior circulation stroke with concurrent ipsilateral symptomatic high-grade (≥70%) atherosclerotic stenosis or occlusion of the extracranial ICA, endovascular ICA revascularization with stenting is superior to intracranial thrombectomy alone with regards to functional outcome at 90 days (measured using the Modified Rankin Scale). EASI-TOC will be conducted at 10-12 high-volume comprehensive stroke centres in Canada. 458 male and female adult (aged ≥ 18 years) patients will be enrolled. Patients will be randomized (1:1) to undergo acute ICA stenting during the thrombectomy procedure (either before or after intracranial thrombectomy, at the discretion of the treating physician) or to intracranial thrombectomy alone without ICA stenting. Deferred ICA intervention is allowed, if indicated. Randomization will be centralized and web-based. Stratification will be performed for use or not of IV alteplase and for enrolling site. Patients will be treated acutely and followed up to one year. Our primary hypothesis assumes a greater proportion of patients with 90-day mRS 0-2 in the stenting group versus the no stenting group (55% versus 40%). Assuming a minimal clinically important difference of 15 % between groups experiencing no crossover, a total of 173 patients per group would be sufficient to detect this difference, with a power of 80 % and a significance level of 5 %. Taking into account a cross-over rate of 10% (5% in either direction) and a loss to follow-up of 5 %, the total sample size will increase to 450 patients. Primary analysis will be by Intention-to-treat. Pre-specified as-treated, sex-specific and subgroup analyses will also be performed. Informed consent will be obtained from patients or their surrogate. Deferral of consent will be allowed if permitted by local ethics committees.