ABSTRACT NUMBER: ESOC2026LB148 LB148 - TENECTEPLASE FOR MEDIUM VESSEL OCCLUSION AT 4.5 TO 24 HOURS AFTER ISCHEMIC STROKE-SECONDARY ANALYSIS OF THE OPTION RANDOMIZED CLINICAL TRIAL

Abstract Background and aims Endovascular treatment has generally not been shown to benefit patients due to medium vessel occlusion (MeVO) stroke. Whether intravenous tenecteplase beyond 4.5 hours improves outcomes in MeVO according to ESCAPE-MeVO and DISTAL criteria is unclear. Methods This is a secondary analysis of the OPTION (Tenecteplase for Acute Non–Large Vessel Occlusion in the Extended Time Window) trial, conducted between June 2, 2023 and August 4, 2025. Patients with non-large vessel occlusion stroke and presence of salvageable tissue on CTP within 4.5 to 24 hours after onset were recruited. Patients were divided into having MeVO vs non-MeVO at presentation as per the ESCAPE-MeVO and DISTAL criteria. The primary outcome was defined as a score of 0 or 1 on the mRS at 90 days. Results A total of 556 enrolled patients were included in the analysis, with 386 (68.2%) having MeVO and 180 (31.8%) having non-MeVO. Patients with MeVO had larger volume of ishemic core, larger perfusion lesion at initial imaging, and higher proportion caused by Cardioembolism than those with non-MeVO. In the MeVO group, the primary outcome following Tenecteplase, compared with standard medical treatment, occurred in 83 (42.6%) patients vs 63 (33.0%) patients (aRR 1.29; 95%CI 1.00-1.66). This beneficial was consistent in patients without MeVO (40 [46.0%] vs. 34 [36.6%]; aRR 1.45; 95%CI 1.05-2.00; P for interaction=0.75). Conclusions This analysis suggests that for patients with MeVO, while EVT did not demonstrate benefit, intravenous Tenecteplase in an extended time window represents a feasible reperfusion strategy. Conflict of interest Table 1 - belongs to Methods Figure 1 - belongs to Results Table 2 - belongs to Conclusions