Evidence that Tenecteplase Is Noninferior to Alteplase for Acute Ischemic Stroke : Meta-Analysis of 5 Randomized Trials

Abstract

Background and Purpose- TNK (tenecteplase), a newer fibrinolytic agent, has practical delivery advantages over ALT (alteplase) that would make it a useful agent if noninferior in acute ischemic stroke treatment outcome. Accordingly, the most recent US American Heart Association/American Stroke Association acute ischemic stroke guideline recognized TNK as an alternative to ALT, but only based on informal consideration, rather than formal meta-analysis, of completed randomized control trials. Methods- Systematic literature search and formal meta-analysis were conducted per PRISMA guidelines (Preferred Reporting Items for Systemic Reviews and Meta-Analyses), adapted to noninferiority analysis. The primary outcome of freedom from disability (modified Rankin Scale score, 0-1) outcome at 3 m, and additional efficacy and safety outcomes, were analyzed. Results- Systematic search identified 5 trials enrolling 1585 patients (828 TNK, 757 ALT). Across all trials, mean age was 70.8, 58.5% male, baseline National Institutes of Health Stroke Scale mean 7.0, and time from last known well to treatment start mean 148 minutes. All ALT patients received standard 0.9 mg/kg dosing, while TNK dosing was 0.1 mg/kg in 6.8%, 0.25 mg/kg in 24.6%, and 0.4 mg/kg in 68.6%. For the primary end point, crude cumulative rates of disability-free (modified Rankin Scale score, 0-1) 3 m outcome were TNK 57.9% versus ALT 55.4%. Informal, random-effects meta-analysis, the risk difference was 4% (95% CI, -1% to 8%). The lower 95% CI bound fell well within the prespecified noninferiority margin. Similar results were seen for the additional efficacy end points: functional independence (modified Rankin Scale score, 0-2): crude TNK 71.9% versus ALT 70.5%, risk difference 2% (95% CI, -3% to 6%); and modified Rankin Scale shift analysis, common odds ratio 1.21 (95% CI, 0.93-1.57). For safety end points, lower event rates reduced power, but point estimates were also consistent with noninferiority Conclusions- Accumulated clinical trial data provides strong evidence that TNK is noninferior to ALT in the treatment of acute ischemic stroke. These findings provide formal support for the recent guideline recommendation to consider TNK an alternative to ALT.