Intraarterial Treatment Versus No Intraarterial Treatment within 24 Hours in Patients with Ischaemic Stroke and Large Infarct on Noncontrast CT (TESLA): A Multicentre, Open-Label, Blinded-Endpoint, Randomised, Controlled, Phase 3 Trial

Background: Noncontrast CT is the most widely utilized stroke imaging method. TESLA aimed to assess the efficacy and safety of intraarterial treatment for large infarct patients identified using noncontrast CT alone.Methods: TESLA was a multicentre, open-label, blinded-endpoint, randomised, controlled trial conducted at 47 U.S. hospitals. Ischaemic stroke patients aged 18-85 years, presenting within 24 hours with anterior-circulation large-vessel occlusion and large infarct on noncontrast CT (Alberta Stroke Program Early CT Score [ASPECTS] 2-5) were randomly assigned (1:1) to receive intraarterial treatment (intervention) or no intraarterial treatment (control). Web-based, permuted-block randomisation was stratified for age, ASPECTS, neurologic deficit, and stroke onset-to-imaging time. The primary outcome was 90-day mean utility-weighted modified Rankin scale (uw-mRS) score (intention-to-treat population). Safety outcomes included 90-day mortality and symptomatic intracranial haemorrhage (as-treated population). A Bayesian model adjusting for ASPECTS determined the posterior probability that intervention would be superior to control. Statistical significance was a one-sided posterior probability ≥0·975. This trial was registered with ClinicalTrials.gov, NCT03805308.Findings: Between July 16, 2019, and October 17, 2022, 300 patients were enrolled (152 intervention and 148 control; 140 [47%] females). Mean 90-day uw-mRS score was 2·93 ± 3·39 among intervention patients versus 2·27 ± 2·98 among control patients (adjusted difference, 0·63 [95%CI -0·09, 1·34]; one-sided posterior probability, 0·96). Ninety-day mRS score 0-3 was more frequent with intervention (30% [45/151] versus 20% [29/146]; risk ratio, 1·50 [95%CI 1·00, 2·26]). Ninety-day mortality (35·3% [53/150] with intervention and 33·3% [49/147] with control) and 24-hour symptomatic haemorrhage (4·0% [6/151] and 1·3% [2/149], respectively) were similar.Interpretation: Among patients with a large infarct on noncontrast CT, intraarterial treatment did not significantly improve functional outcome. The observed signal of benefit for intraarterial treatment should be confirmed in other trials of this imaging approach. There were no safety concerns.Trial Registration: This trial was registered with ClinicalTrials.gov, NCT03805308.Funding: The TESLA trial was funded through unrestricted grants from Medtronic, Cerenovus, Penumbra, Stryker, and Genentech.Declaration of Interest: AJY reports research funding from Medtronic, Cerenovus, Penumbra, Stryker, and Genentech for the current study; consulting fees from Penumbra, Vesalio, Cerenovus, Philips Neurovascular, HCA, and the National Institutes of Health; stock options from Nicolab; equity interest in Insera Therapeutics and Gravity Medical; and serves as co-principal investigator of the CLEAR study (Vesalio) and the OPTIMA registry (Balt), endovascular safety monitor of the MOST trial (NIH), and core imaging lab of the THUNDER (Penumbra) and RECCLAIM 2 (Zoll Circulation) trials. OOZ reports research funding from Medtronic, Cerenovus, Penumbra, Stryker, and Genentech for the current study, and from Microvention for other research; and consulting fees from Stryker, Cerenovus, Penumbra, and Medtronic. All other authors declare no competing interests.Ethical Approval: The study was approved by the ethics committees of all participating centres. All patients or their legally authorized representatives provided written informed consent prior to enrollment.