Tenecteplase Before Thrombectomy at 4.5 to 24 Hours for Basilar Artery Occlusion

Importance: Whether intravenous tenecteplase before endovascular thrombectomy (EVT) improves outcomes in patients with basilar artery occlusion presenting 4.5 to 24 hours after stroke onset remains uncertain. Objective: To evaluate the efficacy and safety of intravenous tenecteplase before EVT vs EVT alone in patients with moderate to severe basilar artery occlusion admitted within 4.5 to 24 hours from stroke onset. Design, Setting, and Participants: This multicenter, open-label, blinded end point, randomized clinical trial was conducted at 40 stroke centers in China. Between March 16, 2023, and February 4, 2025, a total of 330 patients with moderate to severe basilar artery occlusion (National Institutes of Health Stroke Scale score ≥10) presenting within 4.5 to 24 hours from stroke onset to EVT-capable centers were enrolled. Final follow-up was completed on May 4, 2025. Interventions: Patients were randomized 1:1 via a centralized web server using a minimization method to receive either intravenous tenecteplase (bolus injection, 0.25 mg/kg; maximum, 25 mg) followed by EVT (n = 166) or EVT alone (n = 164). Main Outcomes and Measures: The primary outcome was functional independence (modified Rankin Scale score, 0-2) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage and 90-day mortality. Results: Among 332 patients randomized, 2 withdrew consent. Of the remaining 330 patients (mean [SD] age, 66 [11] years; 241 males [73%]; 89 females [27%]), 329 completed 90-day follow-up. Of whom, 50 of 165 (30%) in the tenecteplase plus EVT group and 50 of 164 (30%) in the EVT alone group achieved functional independence (adjusted rate ratio, 0.92 [95% CI, 0.67 to 1.25]; risk difference, -0.18% [95% CI, -10.13% to 9.76%]). Symptomatic intracranial hemorrhage occurred in 8 patients (5%) in the tenecteplase plus EVT group and 6 (4%) in the EVT alone group. Mortality at 90 days was similar between the groups (66 [40%] vs 70 [43%], respectively). Conclusions and Relevance: Among patients with moderate to severe basilar artery occlusion admitted directly to EVT-capable centers who presented 4.5 to 24 hours after stroke onset, the addition of intravenous tenecteplase before EVT did not result in improved functional outcomes compared with EVT alone. Trial Registration: ClinicalTrials.gov Identifier: NCT05701956.