The outcomes of patients with large ischemic core who fail to recanalize with endovascular therapy (EVT) compared to medical management (MM) are uncertain. The objective was to evaluate the clinical and safety outcomes of patients who underwent EVT in patients with large ischemic core and unsuccessful recanalization. This was apost hoc analysis of the ANGEL-ASPECT randomized trial. Unsuccessful recanalization was defined as patients who underwent EVT with eTICI 0-2a. The primary endpoint was 90-day very poor outcome (mRS 5-6). Multivariable logistic regression was conducted controlling for ASPECTS, occlusion location, intravenous thrombolysis, and time to treatment. Of 455 patients 225 were treated with MM. Of 230 treated with EVT, 43 (19%) patients had unsuccessful recanalization. There was no difference in 90-day very poor outcomes (39.5% vs. 40%, aOR 0.93, 95% confidence interval, CI 0.47-1.85, p = 0.95), sICH (7.0% vs. 2.7%, aOR 2.81, 95% CI 0.6-13.29, p = 0.19), or mortality (30% vs. 20%, aOR 1.65, 95% CI 0.89-3.06, p = 0.11) between the unsuccessful EVT and MM groups, respectively. There were higher rates of ICH (55.8% vs. 17.3%, p < 0.001), infarct core volume growth (142.7 ml vs. 90.5 ml, β = 47.77, 95% CI 20.97-74.57 ml, p < 0.001), and decompressive craniectomy (18.6% vs. 3.6%, p < 0.001) in the unsuccessful EVT versus MM groups. In arandomized trial of patients with large ischemic core undergoing EVT with unsuccessful recanalization, there was no difference in very poor outcomes, sICH or death versus medically managed patients. In the unsuccessful EVT group, there were higher rates of any ICH, volume of infarct core growth, and decompressive craniectomy.