Z. Qiu, F. Li, H. Sang, G. Yuan, D. Xie, K. Zhou, M. Li, Z. Meng, Z. Kong, Z. Ruan, C. Li, G. Yang, J. Wu, C. Long, B. Yang, H. Hu, Y. Li, J. Luo
5 min
For patients with acute ischemic stroke caused by large-vessel occlusion who present within 4.5 hours of symptom onset, does administering intravenous tenecteplase prior to endovascular thrombectomy improve functional outcomes compared to performing thrombectomy alone?
The BRIDGE-TNK trial was a multicenter, randomized, open-label study conducted in China. Researchers enrolled 550 patients eligible for thrombolysis and randomized them in a 1:1 ratio to receive either intravenous tenecteplase followed by endovascular thrombectomy or endovascular thrombectomy alone. The primary outcome was functional independence at 90 days, measured by a score of 0 to 2 on the modified Rankin scale (mRS). Secondary outcomes included reperfusion success, quality of life, and safety metrics such as symptomatic intracranial hemorrhage.
The study found that 52.9% of patients in the tenecteplase-thrombectomy group achieved functional independence at 90 days, compared to 44.1% in the thrombectomy-alone group (adjusted risk ratio, 1.18; P=0.04). While the tenecteplase group showed a higher rate of successful reperfusion before the thrombectomy procedure (6.1% vs 1.1%), there was no statistically significant difference in symptomatic intracranial hemorrhage or mortality between the two groups. The authors noted that the observed absolute difference of 8.8 percentage points was clinically meaningful, though it fell short of their initial power calculation assumptions.
Standard practice for large-vessel occlusion stroke often involves 'bridging' therapy—administering a thrombolytic agent before mechanical thrombectomy. While previous meta-analyses of alteplase-based bridging therapy showed no clear benefit over thrombectomy alone, this trial suggests that tenecteplase, which has a longer half-life and higher fibrin specificity, may offer a distinct clinical advantage. These results provide evidence that tenecteplase could be a superior pharmacological partner for mechanical thrombectomy in the acute stroke setting.
BACKGROUND: The safety and efficacy of treatment with intravenous tenecteplase before endovascular thrombectomy in patients with acute ischemic stroke due to large-vessel occlusion remain uncertain. METHODS: In this open-label trial conducted in China, we randomly assigned patients with acute ischemic stroke due to large-vessel occlusion who had presented within 4.5 hours after onset and were eligible for thrombolysis to receive either intravenous tenecteplase followed by endovascular thrombectomy or endovascular thrombectomy alone. The primary outcome was functional independence (a score of 0 to 2 on the modified Rankin scale; range, 0 to 6, with higher scores indicating more severe disability) at 90 days. Secondary outcomes included successful reperfusion before and after thrombectomy. Safety outcomes included symptomatic intracranial hemorrhage within 48 hours and death within 90 days. RESULTS: A total of 278 patients were randomly assigned to the tenecteplase-thrombectomy group and 272 to the thrombectomy-alone group. Functional independence at 90 days was observed in 147 patients (52.9%) in the tenecteplase-thrombectomy group and in 120 patients (44.1%) in the thrombectomy-alone group (unadjusted risk ratio, 1.20; 95% confidence interval, 1.01 to 1.43; P = 0.04). A total of 6.1% of the patients in the tenecteplase-thrombectomy group and 1.1% of those in the thrombectomy-alone group had successful reperfusion before thrombectomy, and 91.4% and 94.1%, respectively, had successful reperfusion after thrombectomy. Symptomatic intracranial hemorrhage within 48 hours occurred in 8.5% of the patients in the tenecteplase-thrombectomy group and in 6.7% of those in the thrombectomy-alone group; mortality at 90 days was 22.3% and 19.9%, respectively. CONCLUSIONS: Among patients with acute ischemic stroke due to large-vessel occlusion who had presented within 4.5 hours after onset, the percentage of patients with functional independence at 90 days was higher with intravenous tenecteplase plus endovascular thrombectomy than with endovascular thrombectomy alone. (Funded by the Chongqing Science and Health Joint Medical Research Project and others; BRIDGE-TNK ClinicalTrials.gov number, NCT04733742.).
Alex: [analytical] Walk me through the statistical architecture. The primary outcome used an intention-to-treat analysis. How much does that choice shape our confidence in the result?
Sam: [steady] ITT is the right call for a clinical trial. It includes every randomized participant in their assigned group regardless of protocol adherence, which protects against selection bias and prevents the result from reflecting only who happened to complete the intervention. The risk ratio for functional independence came in at around one point one eight. Under ITT, that estimate is conservative—which makes it more credible, not less.
Alex: [processing] And the secondary outcomes weren't adjusted for multiplicity, so those are essentially exploratory?
Sam: [measured] Correct. Without multiplicity correction, the confidence intervals on the secondary endpoints are descriptive at best. The reperfusion-before-thrombectomy finding is consistent with the pre-softening hypothesis, but it doesn't carry the inferential weight of the primary outcome. Quality-of-life scores, NIHSS trajectories—interesting, but not the basis for the trial's conclusion. The authors were transparent about that, which matters.
Alex: [deliberate] So the ninety-day functional independence result is the only load-bearing pillar. Everything else is scaffolding around it.
Sam: [grounded, precise] That's right. And even that pillar deserves a careful read. The absolute difference was about eight to nine percentage points—meaningful, but the study was originally powered to detect a thirteen-point difference. The benefit is real, but more modest than the design hypothesis anticipated.
Alex: [analytical edge] Does the open-label design inflate that estimate?
Sam: [grounded, professional] It's a legitimate concern. Open-label trials are susceptible to observer bias, particularly for subjective outcome assessments. The blinded adjudication committee helps, but it doesn't fully eliminate the exposure. It's a limitation you have to carry forward when interpreting the effect size. [[RP_SECTION:generalizability-and-future-research|Generalizability and future research]]
Alex: [reflecting] And generalizability—the trial excluded patients requiring interhospital transfer. That's a substantial portion of real-world stroke presentations.
Sam: [measured, precise] That's the critical constraint. The findings apply to patients who present directly to a thrombectomy-capable center. We don't yet have good data on whether early tenecteplase is safe or effective for patients transferred from peripheral hospitals, where the pharmacological window and logistics look quite different. The RESILIENT DIRECT-TNK trial is addressing some of that gap, and a prospective meta-analysis should help clarify both the mechanism and the boundaries of the effect.
Alex: [summarizing] So the trial delivers a clear, positive signal for the direct-presentation population, with a safety profile that warrants monitoring but doesn't contraindicate the approach—and the outstanding question is whether any of that translates to the transferred patient, which is where most of the real-world complexity lives.
Sam: [warm, concluding] That's a precise read. BRIDGE-TNK moves the bridging-protocol question forward in a meaningful way, but it does so for a specific, relatively favorable subpopulation. The effect is real, the mechanism is coherent, and the limitations are well-characterized. For researchers and clinicians working in this space, it's a solid foundation—with the honest caveat that the harder generalizability questions are still open. Thanks for listening to ResearchPod.