Tenecteplase Versus Alteplase for First-Pass Reperfusion in Basilar Artery Occlusion Stroke Thrombectomy

Objective: The first-pass effect (FPE), defined as excellent reperfusion after a single attempt, is associated with improved outcomes in large vessel occlusion stroke. We evaluated whether intravenous tenecteplase (TNK) compared with alteplase (TPA) increases the likelihood of FPE in basilar artery occlusion (BAO). Methods: We analyzed 163 consecutive BAO patients treated with intravenous TNK or TPA within 4.5 h of last known well across 14 U.S. stroke systems (January 2020–August 2024). Patients with early reperfusion (n = 27) or aborted procedures (n = 3) were excluded. Multivariable ordinal and logistic regression identified predictors of FPE (expanded Thrombolysis in Cerebral Infarction [eTICI] 2c–3) and modified FPE (mFPE, eTICI 2b–3), and FPE/mFPE association with 90-day outcomes (modified Rankin Scale [mRS] 0–3). Results: FPE occurred in 55 of 133 patients (41.4%) and was more frequent with TNK than TPA (51.7% vs 32.9%, p = 0.029). TNK was independently associated with higher odds of FPE (adjusted odds ratio [aOR] 2.37, 95% confidence interval [CI] 1.13–4.98, p = 0.023) and mFPE (aOR 2.74, 95% CI 1.20–6.25, p = 0.017). Both FPE and mFPE were independently associated with ambulatory outcomes at 90-days (FPE: aOR 2.94, 95% CI 1.18–7.33, p = 0.021; mFPE: aOR 5.11, 95% CI 1.81–14.43, p = 0.002). TNK compared with TPA did not show an independent association with functional outcome. Interpretation: In this multicenter BAO cohort, TNK increased the odds of achieving FPE compared with TPA. As FPE strongly predicted functional recovery, these findings suggest TNK may confer a reperfusion advantage with potential clinical benefit, although a direct outcome effect was not demonstrated. ANN NEUROL 2026;99:692–704.