Alteplase versus tenecteplase for thrombolysis after ischaemic stroke (ATTEST): a phase 2, randomised, open-label, blinded endpoint study

Tenecteplase in acute ischemic stroke: Review of the literature and expert consensus from the French Neurovascular Society

BACKGROUND

Intravenous alteplase is the only thrombolytic treatment approved for patients with acute ischemic stroke (AIS). Although no randomized controlled trial (RCT) has shown the superiority of tenecteplase over alteplase in AIS, tenecteplase is increasingly used off-label in Stroke Units. The purpose of the present work was to provide an up-to-date set of expert consensus statements on the use of tenecteplase in AIS.

METHODS

Members of the working group were selected by the French Neurovascular Society. RCTs comparing tenecteplase and alteplase in the treatment of AIS were reviewed. Recent meta-analysis and real-life experience data on tenecteplase published until 30th October 2021 were also analyzed. After a description of the available data, we tried to answer the subsequent questions about the use of tenecteplase in AIS: What dosage of tenecteplase should be preferred? How effective is tenecteplase for cerebral artery recanalization? What is the clinical effectiveness of tenecteplase? What is the therapeutic safety of tenecteplase? What are the benefits associated with tenecteplase ease of use? Then expert consensus statements for tenecteplase use were submitted. In October 2021 the working group was asked to review and revise the manuscript. In November 2021, the current version of the manuscript was approved.

EXPERT CONSENSUS

A set of three expert consensus statements for the use of tenecteplase within 4.5hours of symptom onset in AIS patients were issued: (1) It is reasonable to use tenecteplase 0.25mg/kg when mechanical thrombectomy (MT) is planned. (2) Tenecteplase 0.25mg/kg can be used as an alternative to alteplase 0.9mg/kg in patients with medium- or small-vessel occlusion not retrievable with MT. (3) Tenecteplase 0.25mg/kg could be considered as an alternative to alteplase 0.9mg/kg in patients without vessel occlusion.

CONCLUSIONS

These expert consensus statements could provide a framework to guide the clinical decision-making process for the use of tenecteplase according to admission characteristics of AIS patients. However, existing data are limited, requiring inclusions in ongoing RCTs or real-life registries.

European Stroke Organisation (ESO) expedited recommendation on tenecteplase for acute ischaemic stroke

Within the last year, four randomised-controlled clinical trials (RCTs) have been published comparing intravenous thrombolysis (IVT) with tenecteplase and alteplase in acute ischaemic stroke (AIS) patients with a non-inferiority design for three of them. An expedited recommendation process was initiated by the European Stroke Organisation (ESO) and conducted according to ESO standard operating procedure based on the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework. We identified three relevant Population, Intervention, Comparator, Outcome (PICO) questions, performed systematic reviews of the literature and meta-analyses, assessed the quality of the available evidence, and wrote evidence-based recommendations. Expert consensus statements were provided if insufficient evidence was available to provide recommendations based on the GRADE approach. For patients with AIS of <4.5 h duration who are eligible for IVT, tenecteplase 0.25 mg/kg can be used as a safe and effective alternative to alteplase 0.9 mg/kg (moderate evidence, strong recommendation). For patients with AIS of <4.5 h duration who are eligible for IVT, we recommend against using tenecteplase at a dose of 0.40 mg/kg (low evidence, strong recommendation). For patients with AIS of <4.5 h duration with prehospital management with a mobile stroke unit who are eligible for IVT, we suggest tenecteplase 0.25 mg/kg over alteplase 0.90 mg/kg (low evidence, weak recommendation). For patients with large vessel occlusion (LVO) AIS of <4.5 h duration who are eligible for IVT, we recommend tenecteplase 0.25 mg/kg over alteplase 0.9 mg/kg (moderate evidence, strong recommendation). For patients with AIS on awakening from sleep or AIS of unknown onset who are selected with non-contrast CT, we recommend against IVT with tenecteplase 0.25 mg/kg (low evidence, strong recommendation). Expert consensus statements are also provided. Tenecteplase 0.25 mg/kg may be favoured over alteplase 0.9 mg/kg for patients with AIS of <4.5 h duration in view of comparable safety and efficacy data and easier administration. For patients with LVO AIS of <4.5 h duration who are IVT-eligible, IVT with tenecteplase 0.25 mg/kg is preferable over skipping IVT before MT, even in the setting of a direct admission to a thrombectomy-capable centre. IVT with tenecteplase 0.25 mg/kg may be a reasonable alternative to alteplase 0.9 mg/kg for patients with AIS on awakening from sleep or AIS of unknown onset and who are IVT-eligible after selection with advanced imaging.

Tenecteplase versus alteplase in acute ischaemic cerebrovascular events (TRACE-2): a phase 3, multicentre, open-label, randomised controlled, non-inferiority trial

BACKGROUND

There is increasing interest in replacing alteplase with tenecteplase as the preferred thrombolytic treatment for patients with acute ischaemic stroke. We aimed to establish the non-inferiority of tenecteplase to alteplase for these patients.

METHODS

In this multicentre, prospective, open-label, blinded-endpoint, randomised controlled, non-inferiority trial, adults with an acute ischaemic stroke who were eligible for standard intravenous thrombolysis but ineligible for endovascular thrombectomy were enrolled from 53 centres in China and randomly assigned (1:1) to receive intravenous tenecteplase (0·25 mg/kg, maximum dose of 25 mg) or intravenous alteplase (0·9 mg/kg, maximum dose of 90 mg). Participants had to be able to receive treatment within 4·5 h of stroke, have a modified Rankin Scale (mRS) score of no more than 1 before enrolment, and have a National Institutes of Health Stroke Scale score of 5-25. Patients and treating clinicians were not masked to group assignment; clinicians evaluating outcomes were masked to treatment type. The primary efficacy outcome was the proportion of participants who had a mRS score of 0-1 at 90 days, assessed in the modified intention-to-treat population (all randomly assigned participants who received the allocated thrombolytic), with a non-inferiority margin of 0·937 for the risk ratio (RR). The primary safety outcome was symptomatic intracranial haemorrhage within 36 h, assessed in all participants who received study drug and had a safety assessment available. The trial is registered with ClinicalTrials.gov, NCT04797013, and has been completed.

FINDINGS

Between June 12, 2021, and May 29, 2022, 1430 participants were enrolled and randomly assigned to tenecteplase (n=716) or alteplase (n=714). Six patients assigned to tenecteplase and seven to alteplase did not receive study product, and five participants in the tenecteplase group and 11 in the alteplase group were lost to follow-up at 90 days. The primary outcome in the modified intention-to-treat population occurred in 439 (62%) of 705 in the tenecteplase group versus 405 (58%) of 696 in the alteplase group (RR 1·07, 95% CI 0·98-1·16). The lower limit of the RR's 95% CI was greater than the non-inferiority margin. Symptomatic intracranial haemorrhage within 36 h was observed in 15 (2%) of 711 in the tenecteplase group and 13 (2%) of 706 in the alteplase group (RR 1·18, 95% CI 0·56-2·50). Mortality within 90 days occurred in 46 (7%) individuals in the tenecteplase group versus 35 (5%) in the alteplase group (RR 1·31, 95% CI 0·86-2·01).

INTERPRETATION

Tenecteplase was non-inferior to alteplase in people with ischaemic stroke who were eligible for standard intravenous thrombolytic but ineligible for or refused endovascular thrombectomy.

FUNDING

National Science and Technology Major Project, Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, National Natural Science Foundation of China, and China Shijiazhuang Pharmaceutical Company Recomgen Pharmaceutical (Guangzhou).

A Phase III, prospective, double-blind, randomized, placebo-controlled trial of thrombolysis in imaging-eligible, late-window patients to assess the efficacy and safety of tenecteplase (TIMELESS): Rationale and design

RATIONALE

While thrombolysis is standard of care for patients with acute ischemic stroke (AIS) within 4.5 h of symptom onset, the benefit of tenecteplase beyond this time window is less certain.

AIM

The TIMELESS trial (NCT03785678) aims to determine if treatment with tenecteplase increases the proportion of good clinical outcomes among patients with stroke due to a large vessel occlusion who present beyond 4.5 h after symptom onset.

SAMPLE SIZE ESTIMATES

A total of 456 patients will provide ⩾90% power to detect differences in the distribution of modified Rankin Scale scores at Day 90 at the two-sided 0.049 significance level.

METHODS AND DESIGN

TIMELESS is a Phase III, double-blind, randomized, placebo-controlled trial of tenecteplase with or without endovascular thrombectomy in patients with AIS and evidence of salvageable tissue via imaging who present within the 4.5- to 24-h time window with an internal carotid artery (ICA) or middle cerebral artery (MCA) (M1/M2) occlusion.

STUDY OUTCOMES

The primary efficacy objective of tenecteplase compared with placebo will be evaluated with ordinal modified Rankin Scale scores at Day 90. Safety will be evaluated via incidence of symptomatic intracranial hemorrhage, incidence and severity of adverse events, and mortality rate.

DISCUSSION

Results from TIMELESS will contribute to understanding of the safety and efficacy of tenecteplase administered 4.5-24 h following symptom onset for patients with an ICA or MCA occlusion.

The efficacy and safety of tenecteplase versus alteplase for acute ischemic stroke: an updated systematic review, pairwise, and network meta-analysis of randomized controlled trials

Tenecteplase (TNK) is a promising candidate to replace alteplase as the standard of care for acute ischemic stroke (AIS); however, the optimal dosage is still to be investigated. Therefore, we aim to evaluate the safety and efficacy of TNK versus alteplase and to investigate the optimal TNK dosage. A systematic review, pairwise, and network meta-analysis synthesizing randomized controlled trials (RCTs) from WOS, SCOPUS, EMBASE, and PubMed until July 26th, 2022. We used the risk ratio (RR) for dichotomous outcomes presented with the corresponding 95% confidence interval (CI). We registered our protocol in PROSPERO with ID: CRD42022352038. Nine RCTs with a total of 3,707 patients were included. TNK significantly led to complete recanalization (RR: 1.27 with 95% CI [1.02, 1.57], P = 0.03); however, we found no difference regarding early neurological improvement (RR: 1.07 with 95% CI [0.94, 1.21], P = 0.33) and excellent neurological recovery (RR: 1.03 with 95% CI [0.96, 1.10], P = 0.42). Also, TNK was similar to alteplase regarding mortality (RR: 0.99 with 95% CI [0.82, 1.18], P = 0.88), intracranial haemorrhage (RR: 1.00 with 95% CI [0.85, 1.18], P = 0.99), and parenchymal hematoma (RR: 1.13 with 95% CI [0.83, 1.54], P = 0.44). TNK in the dose of 0.25 mg is a viable candidate to displace alteplase as the standard of care in patients with an AIS within 4.5 h of presentation due to its better rate of early neurological recovery and non-inferiority in terms of safety outcomes. However, the evidence regarding TNK's role in AIS presenting after 4.5 h from symptoms onset, wake-up stroke, and minor stroke/TIA is still lacking, necessitating further double-blinded pragmatic RCTs in this regard.

Endovascular treatment for ischemic stroke patients with and without atrial fibrillation, and the effects of adjunctive pharmacotherapy: a narrative review

INTRODUCTION

Endovascular thrombectomy (EVT) is associated with good clinical outcomes in patients with ischemic stroke, but the impact of EVT on clinical outcomes in patients with ischemic stroke with and without atrial fibrillation (AF), and the effect of adjunctive pharmacological therapies with EVT, remains unclear.

AREAS COVERED

The goal of this narrative review is to provide an overview of studies which have examined: 1) associations between EVT and outcomes for patients following ischemic stroke, 2) associations between EVT and outcomes for patients following ischemic stroke with and without AF , including function, reperfusion, hemorrhage, and mortality, 3) the effect of adjunctive pharmacological therapies peri- and post-thrombectomy, and 4) integration of prehospital care on endovascular treatment outcomes.

EXPERT OPINION

There is little evidence from randomized controlled trials on the effect of AF on stroke outcomes following EVT and the safety and efficacy of AF treatment in the peri-EVT such as tirofiban or Intravenous thrombolysis with Non-vitamin K Antagonist Oral Anticoagulant. The available evidence from observational studies on AF and EVT outcomes is inconsistent, but factors such as procedural EVT devices, the center volume, clinician experience, stroke recognition, and inclusion criteria of studies have all been associated with poorer clinical outcomes. Enhancing the clinical network among prehospital and hospitals will facilitate direct transfer to EVT centers, reducing stroke onset to EVT time and optimizing stroke outcomes.

Tenecteplase vs. alteplase for treatment of acute ischemic stroke: A systematic review and meta-analysis of randomized trials

Background and objectives

Several randomized controlled trials (RCTs) have compared tenecteplase to alteplase for treatment of acute ischemic stroke (AIS). Yet, there is no meta-analysis that includes the latest published RCTs of 2022. We sought to compare the safety and efficacy of tenecteplase vs. alteplase for the treatment of AIS through a meta-analysis of all published RCTs.

Methods

A systematic literature review of the English language literature was conducted using PubMed, Web of Science, Scopus, and Embase. We included RCTs that focused on patients with AIS treated with tenecteplase and alteplase. Multiple reviewers screened through potential studies to identify the final papers included in our analysis. Following PRISMA guidelines, multiple authors extracted data to ensure accuracy. Data were pooled using a random-effects model.

Results

Nine trials, with 3,706 patients, compared outcomes of patients treated with tenecteplase and alteplase for AIS. Both treatments resulted in comparable rates of modified Rankin Scale (mRS) 0-1 at 90 days (RR = 1.03; 95% CI = 0.97-1.10; P-value = 0.359) and mRS 0-2 at 90 days (RR = 1.03; 95% CI = 0.87-1.22; P-value = 0.749). There was no heterogeneity among included studies regarding mRS 0-1 rates (I² = 26%; P-value = 0.211); however, there was significant heterogeneity in mRS 0-2 rates (I² = 71%; P-value = 0.002). Similarly, rates of mortality (RR = 0.97; 95% CI = 0.81-1.16; P-value = 0.746) and symptomatic intracranial hemorrhage (sICH) rates (RR = 1.10; 95% CI = 0.75-1.61; P-value = 0.622) were comparable in both treatment groups. There was no significant heterogeneity among included studies in either mortality (I² = 30%; P-value = 0.181) or sICH (I² = 0%; P-value = 0.734) rates. Further analysis comparing dosing of tenecteplase (0.1, 0.25, 0.32, and 0.4 mg/kg) yielded no significant differences for any of the endpoints (mRS 0-1, mRS 0-2, sICH, and mortality) compared to alteplase.

Discussion

Based on available evidence from completed RCTs, tenecteplase has proven similar safety and efficacy to alteplase for treatment of AIS.

Effect of intravenous thrombolysis on core growth rate in patients with acute cerebral infarction

Objective

This study aimed to investigate the effects of recombinant tissue plasminogen activator intravenous thrombolysis (IVT) on the core growth rate of acute ischemic stroke.

Methods

Stroke patients with large vessel occlusion and non-recanalization from IVT treatment were retrospectively included in this study and divided into two groups: IVT and non-IVT. The core growth rate was estimated by the acute core volume on perfusion CT divided by the last known well time from stroke to CT perfusion. The primary endpoint was the core growth rate, the tissue outcome was 24 h-ASPECTS, and the clinical outcome was a 3-month modified Rankin score.

Results

A total of 94 patients were included with 53 in the IVT group and 41 in the non-IVT group. There was no significant difference in age, gender, hypertension, diabetes, atrial fibrillation, acute NIHSS, and last known well time from stroke to CT perfusion acquisition between the two groups. The core growth rate in the IVT group was lower than that in the non-IVT group, which was statistically significant after multivariate adjustment (coefficient: -5.20, 95% CI= [-9.85, -0.56], p = 0.028). There was a significant interaction between the IVT and the collateral index in predicting the core growth rate. The analysis was then stratified according to the collateral index, and the results suggested that IVT reduced the core growth rate more significantly after the worsening of collateral circulation (coefficient: 15.38, 95% CI= [-26.25, -4.40], p = 0.007). The 3-month modified Rankin score and 24 h-ASPECTS were not statistically significant between the two groups.

Conclusion

Intravenous thrombolysis reduces the core growth rate in patients with AIS, especially those with poor collateral status.

Replacing Alteplase with Tenecteplase: Is the Time Ripe?

Thrombolysis for acute ischemic stroke has predominantly been with alteplase for over a quarter of a century. In recent years, with trials showing evidence of higher rates of successful reperfusion, similar safety profile and efficacy of tenecteplase (TNK) as compared to alteplase, TNK has now emerged as another potential choice for thrombolysis in acute ischemic stroke. In this review, we will focus on these recent advances, aiming: (1) to provide a brief overview of thrombolysis in stroke; (2) to provide comparisons between alteplase and TNK for clinical, imaging, and safety outcomes; (3) to focus on key subgroups of interest to understand if there is an advantage of using TNK over alteplase or vice-versa, to review available evidence on role of TNK in intra-arterial thrombolysis, as bridging therapy and in mobile stroke units; and (4) to summarize what to expect in the near future from recently completed trials and propose areas for future research on this evolving topic. We present compelling data from several trials regarding the safety and efficacy of TNK in acute ischemic stroke along with completed yet unpublished trials that will help provide insight into these unanswered questions.

Comparison of dosing errors between tenecteplase and alteplase for management of acute ischemic stroke

BACKGROUND

Acute ischemic stroke (AIS) is a medical emergency leading to morbidity and mortality. Thrombolytic therapy is currently the mainstay for the management of AIS owing to its improvement in neurologic function at 3 months.

OBJECTIVES

The objective of this study was to compare the frequency of dosing errors made with tenecteplase versus alteplase administration in management of AIS. The secondary objectives evaluated efficacy outcomes of intensive care unit length of stay (LOS), hospital LOS, and time from door to needle and safety outcomes of bleeding and all-cause mortality between groups.

METHODS

This multicenter retrospective cohort study included patients with AIS treated with thrombolytics (tenecteplase or alteplase). The study evaluated patients at 9 different hospitals in a Texas Network between August 2018 and August 2020.

RESULTS

There were 3808 patients evaluated for inclusion and 359 were included: 171 in the tenecteplase group and 188 in the alteplase group. There were no differences found in dosing errors between tenecteplase and alteplase (25.7% vs. 32.4%, P = 0.16). There was no difference in all-cause mortality (tenecteplase 1.8% vs. alteplase 5.3%, P = 0.09) or bleeding events (tenecteplase 8.8% vs. alteplase 7.4%, P = 0.64). Patients who received tenecteplase had improved door to needle time < 60 minutes (tenecteplase 60% vs. alteplase 49%, P = 0.04).

CONCLUSION

There was no difference in dosing errors between tenecteplase and alteplase for the management of AIS. Tenecteplase was associated with shorter door to needle times, which may be caused by simpler administration times. Institutions could consider strategies to mitigate dosing errors for thrombolytic therapies.

External Validation of e-ASPECTS Software for Interpreting Brain CT in Stroke

OBJECTIVE

The purpose of this study was to test e-ASPECTS software in patients with stroke. Marketed as a decision-support tool, e-ASPECTS may detect features of ischemia or hemorrhage on computed tomography (CT) imaging and quantify ischemic extent using Alberta Stroke Program Early CT Score (ASPECTS).

METHODS

Using CT from 9 stroke studies, we compared software with masked experts. As per indications for software use, we assessed e-ASPECTS results for patients with/without middle cerebral artery (MCA) ischemia but no other cause of stroke. In an analysis outside the intended use of the software, we enriched our dataset with non-MCA ischemia, hemorrhage, and mimics to simulate a representative "front door" hospital population. With final diagnosis as the reference standard, we tested the diagnostic accuracy of e-ASPECTS for identifying stroke features (ischemia, hyperattenuated arteries, and hemorrhage) in the representative population.

RESULTS

We included 4,100 patients (51% women, median age = 78 years, National Institutes of Health Stroke Scale [NIHSS] = 10, onset to scan = 2.5 hours). Final diagnosis was ischemia (78%), hemorrhage (14%), or mimic (8%). From 3,035 CTs with expert-rated ASPECTS, most (2084/3035, 69%) e-ASPECTS results were within one point of experts. In the representative population, the diagnostic accuracy of e-ASPECTS was 71% (95% confidence interval [CI] = 70-72%) for detecting ischemic features, 85% (83-86%) for hemorrhage. Software identified more false positive ischemia (12% vs 2%) and hemorrhage (14% vs <1%) than experts.

INTERPRETATION

On independent testing, e-ASPECTS provided moderate agreement with experts and overcalled stroke features. Therefore, future prospective trials testing impacts of artificial intelligence (AI) software on patient care and outcome are required before widespread implementation of stroke decision-support software. ANN NEUROL 2022;92:943-957.

Different dosing regimens of Tenecteplase in acute ischemic stroke: A network meta-analysis of the clinical evidence

Introduction:

Acute ischemic stroke remains the major cause of death and disability and conclusive evidence of Tenecteplase in treating stroke is lacking.

Objective:

To conduct a meta-analysis to determine whether Tenecteplase produces better outcomes than Alteplase and a network meta-analysis comparing the different dosing regimens of Tenecteplase.

Methods:

Searches were made in MEDLINE, CENTRAL, and ClinicalTrials.gov. The outcome measures are recanalization, early neurological improvement, functional outcomes at 90 days (modified Rankin Scale 0–1 and 0–2), intracranial hemorrhage, symptomatic intracranial hemorrhage, and mortality within 90 days from treatment.

Results:

Fourteen studies are included in the meta-analyses and 18 studies in the network meta-analyses. In the meta-analysis, Tenecteplase 0.25 mg/kg has significant results in early neurological improvement (OR = 2.35, and 95% CI = 1.16–4.72) and excellent functional outcome (OR = 1.20, and 95% CI = 1.02–1.42). In the network meta-analysis, Tenecteplase 0.25 mg/kg produces significant results in early neurological improvement (OR = 1.52 [95% CI = 1.13–2.05], p-value = 0.01), functional outcomes (mRS 0–1 and 0–2) (OR = 1.19 [95% CI = 1.03–1.37], p-value = 0.02; OR = 1.21 [95% CI = 1.05–1.39], p-value = 0.01; respectively) and mortality (OR = 0.78 [95% CI = 0.64–0.96], p-value = 0.02) whereas Tenecteplase 0.40 mg/kg increases the chances of symptomatic intracranial hemorrhage (OR = 2.35 [95% CI = 1.19–4.64], p-value = 0.01).

Conclusion:

While not conclusive, our study lends evidence to 0.25 mg/kg Tenecteplase dose for ischemic stroke treatment. Further randomized trials need to be done to validate this finding.

Registration:

International prospective register of systematic reviews (PROSPERO) – CRD42022339774 URL: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=339774

Tenecteplase or Alteplase Better in Patients with Acute Ischemic Stroke Due to Large Vessel Occlusion: A Single Center Observational Study

Background and Objectives: The study aimed to investigate the efficacy of intravenous thrombolysis with Tenecteplase before thrombectomy for acute ischemic stroke (AIS) patients compared with previous results using Alteplase. Previous trials for Tenecteplase have indicated an increased incidence of vascular reperfusion. In April 2021, we started to primarily give Tenecteplase to patients eligible to undergo thrombectomy. Materials and Methods: In this retrospective observational single-center non-randomized study, we analyzed directly admitted patients with AIS who had occlusion of the internal carotid, middle cerebral, or basilar artery and who underwent thrombectomy, as well as the recanalization rate for these patients at the first angiographic assessment (mTICI score 2b–3), and complications. Results: We included 184 patients (demographic characteristics did not differ between Tenecteplase and Alteplase groups (mean age 68.4 vs. 73.0 years; female sex 53.3% vs. 51.1%, NIHSS 14 (IQR 4–26) vs. 15 (2–31). Forty-five patients received Tenecteplase and 139 Alteplase before endovascular treatment (EVT). Pre-EVT (endovascular treatment) recanalization was more likely to occur with Tenecteplase rather than Alteplase (22.2% vs. 8.6%, p = 0.02). Successful reperfusion (mTICI 2b–3) after EVT was achieved in 155 patients (42 (93.4%) vs. 113 (81.3), p = 0.07). Hemorrhagic imbibition occurred in 15 (33.3%) Tenecteplase-treated patients compared with 39 (28.1%) Alteplase-treated patients (p = 0.5). Patients treated with Tenecteplase had higher odds of excellent functional outcome than Alteplase-treated patients (Tenecteplase 48.6% vs. Alteplase 26.1%; OR 0.37 (95% CI 0.17–0.81), p = 0.01). Conclusions: Tenecteplase (25 mg/kg) could have superior clinical efficacy over Alteplase for AIS patients with large-vessel occlusion (LVO), administered before EVT. The improvement in reperfusion rate and the better excellent functional outcome could come without an increased safety concern.

Dual thrombolytic therapy with mutant pro-urokinase and small bolus alteplase for ischemic stroke (DUMAS): study protocol for a multicenter randomized controlled phase II trial

Background

The effectiveness of alteplase for ischemic stroke treatment is limited, partly due to the occurrence of intracranial and extracranial hemorrhage. Mutant pro-urokinase (m-proUK) does not deplete fibrinogen and lyses fibrin only after induction with alteplase. Therefore, this treatment has the potential to be safer and more efficacious than treatment with alteplase alone. The aim of this study is to assess the safety and efficacy of thrombolytic treatment consisting of a small bolus alteplase followed by m-proUK compared with standard thrombolytic treatment with alteplase in patients presenting with ischemic stroke.

Methods

DUMAS is a multicenter, phase II trial with a prospective randomized open-label blinded end-point (PROBE) design, and an adaptive design for dose optimization. Patients with ischemic stroke, who meet the criteria for treatment with intravenous (IV) alteplase can be included. Patients eligible for endovascular thrombectomy are excluded. Patients are randomly assigned (1:1) to receive a bolus of IV alteplase (5mg) followed by a continuous IV infusion of m-proUK (40 mg/h during 60 min) or usual care with alteplase (0.9 mg/kg). Depending on the results of interim analyses, the dose of m-proUK may be revised to a lower dose (30 mg/h during 60 min) or a higher dose (50 mg/h during 60 min). We aim to include 200 patients with a final diagnosis of ischemic stroke. The primary outcome is any post-intervention intracranial hemorrhage (ICH) on neuroimaging at 24 h according to the Heidelberg Bleeding Classification, analyzed with binary logistic regression. Efficacy outcomes include stroke severity measured with the National Institutes of Health Stroke Scale (NIHSS) at 24 h and 5–7 days, score on the modified Rankin scale (mRS) assessed at 30 days, change (pre-treatment vs. post-treatment) in abnormal perfusion volume, and blood biomarkers of thrombolysis at 24 h. Secondary safety endpoints include symptomatic intracranial hemorrhage, death, and major extracranial hemorrhage. This trial will use a deferred consent procedure.

Discussion

When dual thrombolytic therapy with a small bolus alteplase and m-proUK shows the anticipated effect on the outcome, this will lead to a 13% absolute reduction in the occurrence of ICH in patients with ischemic stroke.

Trial registration

NL7409 (November 26, 2018)/NCT04256473 (February 5, 2020)

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06596-z.

Alteplase or tenecteplase for thrombolysis in ischemic stroke: An illustrated review

Intravenous thrombolysis is a standard of care treatment for patients with acute ischemic stroke. Tissue plasminogen activator (tPA) has been the main thrombolytic agent used since the publication of the seminal National Institutes of Neurological Disorders and Stroke trial in 1995. There is now mounting evidence to support the routine use of Tenecteplase (TNK) to treat acute ischemic stroke. TNK is a genetically modified tPA with higher fibrin specificity, longer half-life, and reduced systemic coagulopathy. In this illustrated review, we compare the indications, doses, mechanisms of action, efficacy and safety of TNK and tPA. We provide an overview of published clinical trials studying TNK in acute ischemic stroke, including dose-escalation studies and head-to-head comparisons with tPA. Finally, we summarize current acute stroke guideline recommendations and suggest treatment algorithms to manage the two main complications of intravenous thrombolysis: symptomatic intracerebral hemorrhage and angioedema.

Tenecteplase or Alteplase: What Is the Thrombolytic Agent of the Future?

Purpose of review

Alteplase has been the thrombolytic of choice for acute ischaemic stroke for more than two decades. A thrombolytic which is easier to administer and with improved or comparable safety and efficacy is desirable. Tenecteplase has emerged as a potential successor, and its off-license use in acute ischaemic stroke has increased in recent years. We aimed to examine the evidence base for each drug and discuss their use in varying patient populations in acute ischaemic stroke.

Recent findings

Several trials comparing tenecteplase and alteplase have reported very recently with the results of the ACT trial strengthening the argument in favour of non-inferiority of tenecteplase to alteplase. Ongoing trials such as ATTEST-2 are of interest, and trials such as TASTE and TEMPO-2 will shed further light on use of tenecteplase in specific populations.

Summary

A single thrombolytic agent for all indications for thrombolysis in acute ischaemic stroke is desirable in streamlining workflows. Based on recent and upcoming trials, guidelines may soon recommend tenecteplase as a suitable alternative to alteplase. The use of tenecteplase in specific subgroups will depend on further recruitment to ongoing clinical trials.

Intravenous tenecteplase compared with alteplase for acute ischaemic stroke in Canada (AcT): a pragmatic, multicentre, open-label, registry-linked, randomised, controlled, non-inferiority trial

BACKGROUND

Intravenous thrombolysis with alteplase bolus followed by infusion is a global standard of care for patients with acute ischaemic stroke. We aimed to determine whether tenecteplase given as a single bolus might increase reperfusion compared with this standard of care.

METHODS

In this multicentre, open-label, parallel-group, registry-linked, randomised, controlled trial (AcT), patients were enrolled from 22 primary and comprehensive stroke centres across Canada. Patients were eligible for inclusion if they were aged 18 years or older, with a diagnosis of ischaemic stroke causing disabling neurological deficit, presenting within 4·5 h of symptom onset, and eligible for thrombolysis per Canadian guidelines. Eligible patients were randomly assigned (1:1), using a previously validated minimal sufficient balance algorithm to balance allocation by site and a secure real-time web-based server, to either intravenous tenecteplase (0·25 mg/kg to a maximum of 25 mg) or alteplase (0·9 mg/kg to a maximum of 90mg; 0·09 mg/kg as a bolus and then a 60 min infusion of the remaining 0·81 mg/kg). The primary outcome was the proportion of patients who had a modified Rankin Scale (mRS) score of 0-1 at 90-120 days after treatment, assessed via blinded review in the intention-to-treat (ITT) population (ie, all patients randomly assigned to treatment who did not withdraw consent). Non-inferiority was met if the lower 95% CI of the difference in the proportion of patients who met the primary outcome between the tenecteplase and alteplase groups was more than -5%. Safety was assessed in all patients who received any of either thrombolytic agent and who were reported as treated. The trial is registered with ClinicalTrials.gov, NCT03889249, and is closed to accrual.

FINDINGS

Between Dec 10, 2019, and Jan 25, 2022, 1600 patients were enrolled and randomly assigned to tenecteplase (n=816) or alteplase (n=784), of whom 1577 were included in the ITT population (n=806 tenecteplase; n=771 alteplase). The median age was 74 years (IQR 63-83), 755 (47·9%) of 1577 patients were female and 822 (52·1%) were male. As of data cutoff (Jan 21, 2022), 296 (36·9%) of 802 patients in the tenecteplase group and 266 (34·8%) of 765 in the alteplase group had an mRS score of 0-1 at 90-120 days (unadjusted risk difference 2·1% [95% CI - 2·6 to 6·9], meeting the prespecified non-inferiority threshold). In safety analyses, 27 (3·4%) of 800 patients in the tenecteplase group and 24 (3·2%) of 763 in the alteplase group had 24 h symptomatic intracerebral haemorrhage and 122 (15·3%) of 796 and 117 (15·4%) of 763 died within 90 days of starting treatment INTERPRETATION: Intravenous tenecteplase (0·25 mg/kg) is a reasonable alternative to alteplase for all patients presenting with acute ischaemic stroke who meet standard criteria for thrombolysis.

FUNDING

Canadian Institutes of Health Research, Alberta Strategy for Patient Oriented Research Support Unit.

Tenecteplase vs. alteplase for the treatment of patients with acute ischemic stroke: a systematic review and meta-analysis

BACKGROUND

At present, studies regarding the efficacy and safety of tenecteplase for the treatment of patients with acute ischemic stroke (AIS) are still limited and inconsistent. The purpose of this systematic review and meta-analysis is to compare the efficacy and safety of tenecteplase with alteplase for the treatment of AIS patients.

METHODS

Literature search was conducted in PubMed, Embase, and Cochrane Library up to May 10, 2022. Primary outcomes of this study included 90-day good outcome (defined as an mRS score of 0-2) and 90-day excellent outcome (defined as an mRS score of 0-1). Risk ratios (RRs) with 95% confidence intervals (95% CIs) were calculated using a random-effect model for each outcome.

RESULTS

Fourteen studies with a total of 3537 patients were finally included in this meta-analysis. There was no statistical difference between patients receiving tenecteplase and those receiving alteplase in the rates of 90-day good outcome (RR 1.01; 95% CI 0.91-1.13; P = 0.79) and 90-day excellent outcome (RR 1.04; 95% CI 0.92-1.19; P = 0.50). Patients receiving tenecteplase might associated with higher incidence of early neurologic improvement compared with those receiving alteplase (RR 1.29; 95% CI 1.04-1.61; P = 0.02). In addition, no statistical difference was observed between the two groups in other outcomes.

CONCLUSION

This meta-analysis indicated that tenecteplase in AIS patients is as safe and effective as alteplase and might provide more benefit than alteplase. However, due to several inherent limitations of this study, more prospective studies should be conducted to confirm the above results.

Short-Term Efficacy Outcomes of Tenecteplase versus Alteplase for Acute Ischemic Stroke: A Meta-Analysis of 5 Randomized Trials

Tenecteplase (TNK) has been shown to be noninferior to Alteplase (ALT) for long term efficacy and safety outcomes. Whether this also applies to short term efficacy outcomes such as early clinical improvement and recanalization is unknown. To compare TNK and ALT regarding the short term efficacy outcomes: early neurological improvement and recanalization. The PRISMA was used to conduct a meta analysis, adapted to noninferiority analysis. The primary outcome was early (24-72 h) neurological improvement, defined as either NIHSS score 0 or reduction of at least 8 points compared to baseline. Recanalization was a secondary outcome. The noninferiority margin was set at 6.5%. Search strategy yielded 5 randomized clinical trials (1585 patients: 828 TNK, 757 ALT). Mean age was 70.8, 58.8% were men, mean baseline NIHSS was 7, and mean onset to treatment time was 148 min. Patients in intervention group received TNK at doses of 0.1 mg/kg (6.8%), 0.25 mg/kg (24.6%), and 0.4 mg/kg (68.6%), while all ALT patients received 0.9 mg/kg. In random effects meta analysis, TNK was noninferior to ALT for the primary outcome, early major neurological improvement (risk difference 8% in favor of TNK, 95% CI 1%-15%). Recanalization was also noninferior for the TNK compared to the ALT group (risk difference 9% in favor of TNK, 95% CI 6% to 23%). Fixed effects models yielded similarly noninferior results and signaled for a possible TNK superiority for both early neurological improvement and recanalization. TNK is noninferior to ALT at the short term efficacy outcomes: early neurological improvement and recanalization.

IV thrombolysis with tenecteplase for the treatment of acute ischemic stroke

OBJECTIVE

Intravenous thrombolysis (IVT) with tenecteplase has been associated with better clinical outcomes in acute ischemic stroke (AIS) patients with confirmed large vessel occlusions compared to IVT with alteplase. However, the utility of tenecteplase for the treatment of all AIS patients eligible for IVT has not been established.

METHODS

We compared the safety and efficacy of tenecteplase vs. alteplase in AIS patients by analysing propensity score matched data from 20 centres participating in the SITS-ISTR registry. Patients receiving IVT with tenecteplase were matched with up to three patients receiving alteplase from the same centre. The primary outcome of interest was the distribution of 3-month functional outcomes. Secondary outcomes included the rates of patients with symptomatic intracranial hemorrhage (SICH) in the first 24 hours, excellent (mRS-scores of 0-1) or good (mRS-scores of 0-2) functional outcome, and all-cause mortality at 3 months.

RESULTS

A total of 331 tenecteplase-treated AIS patients were matched to 797 patients treated with alteplase [median age of 70 years; 43.9% women; median NIHSS-score: 11 (IQR: 6-17)]. Patients treated with tenecteplase had better three-month functional outcomes (common OR=1.54,95%CI:1.18-2.00) with higher odds of good functional outcome (OR=2.00,95%CI:1.45-2.77) and a lower likelihood of all-cause mortality (OR=0.43,95%CI:0.27-0.67) at three months, compared to alteplase-treated patients. No difference was found in the likelihood of the three-month excellent functional outcomes (OR=1.31,95%CI:0.96-1.78) and 24-hour SICH (1.0% vs. 1.3%; OR=0.72,95%CI:.20-2.64).

INTERPRETATION

IVT with tenecteplase was associated with better three-month clinical outcomes compared to IVT with alteplase in AIS patients, with no increased risk of symptomatic intracranial bleeding. This article is protected by copyright. All rights reserved.

The Development of Novel Drug Treatments for Stroke Patients: A Review

Acute ischemic stroke is a critical condition that can result in disability and death. The consequences of this medical condition depend on various factors, including the size of the stroke, affected brain region, treatment onset, and the type of treatment. The primary objective of stroke treatment is to restart ischemic penumbra tissue perfusion and reduce infarct volume by sustaining blood flow. Recent research on the condition's pathological pathways and processes has significantly improved treatment options beyond restoring perfusion. Many studies have concentrated on limiting injury severity via the manipulation of molecular mechanisms of ischemia, particularly in animal research. This article reviews completed and ongoing research on the development of acute ischemic stroke drugs. This study focuses on three main categories of antithrombotic drugs, thrombolytic drugs, and neuroprotective agents. The paper outlines findings from animal and clinical trials and explores the working mechanisms of these drugs.

The End of Tissue-Type Plasminogen Activator's Reign?

Mechanical thrombectomy is a highly effective treatment for acute ischemic stroke caused by large-vessel occlusion in the anterior cerebral circulation, significantly increasing the likelihood of recovery to functional independence. Until recently, whether intravenous thrombolysis before mechanical thrombectomy provided additional benefits to patients with acute ischemic stroke-large-vessel occlusion remained unclear. Given that reperfusion is a key factor for clinical outcome in patients with acute ischemic stroke-large-vessel occlusion and the efficacy of both intravenous thrombolysis and mechanical thrombectomy is time-dependent, achieving complete reperfusion with a single pass should be the primary angiographic goal. However, it remains undetermined whether extending the procedure with additional endovascular attempts or local lytics administration safely leads to higher reperfusion grades and whether there are significant public health and cost implications. Here, we outline the current state of knowledge and research avenues that remain to be explored regarding the consistent therapeutic benefit of intravenous thrombolysis in anterior circulation strokes and the potential place of adjunctive intra-arterial lytics administration, including alternative thrombolytic agent place.

Efficacy and Safety of Recombinant Human Prourokinase in Acute Ischemic Stroke: A Phase IIa Randomized Clinical Trial

Recombinant human prourokinase (rhPro-UK) is a novel thrombolytic that has been approved to treat patients with acute myocardial infarction. However, the safety and efficacy of intravenous rhPro-UK in patients with acute ischemic stroke (AIS) has not been well established. We aimed to investigate the safety and preliminary efficacy of rhPro-UK in patients with AIS in a multi-center phase IIa trial setting. One hundred nineteen patients within 4.5 h of AIS onset were enrolled in this randomized, open-label, 23-center phase IIa clinical trial. Patients were randomly assigned to 35 mg (n = 40) or 50 mg (n = 39) intravenous rhPro-UK or 0.9 mg/kg recombinant tissue plasminogen activator (r-tPA; n = 40). The primary endpoint was functional independence defined as a modified Rankin scale (mRS) score of 0 or 1 at 90 days. The secondary outcome was early neurological improvement defined as a reduction of ≥ 4 points on the National Institutes of Health Stroke Scale (NIHSS) score from baseline to 24 h after drug administration. Safety endpoints included death due to any cause, symptomatic intracerebral hemorrhage (sICH), and other serious adverse events (SAEs). The proportion of patients with an mRS score of ≤ 1 at 90 days did not differ significantly among three groups (35 mg rhPro-UK: 55.56% vs. 50 mg rhPro-UK: 57.89% vs. vs. r-tPA: 52.63%; P = 0.92). The rates of treatment response, referring to early neurological improvement, were similar among these three groups (36.11% vs. 31.58% vs. 28.95%, respectively; P = 0.85). There was no difference in mortality at 90 days or in the rate of other SAEs among the three groups. One patient in the 50 mg rhPro-UK group suffered sICH. While neither the primary efficacy outcomes nor safety profile differed significantly among the low, high rhPro-UK and control groups, it is a logical step to further test the low-dose rhPro-UK group versus the control group in a well-powered phase III study.Trial Registration: http://www.chictr.org.cn . Identifier: ChiCTR1800016519. Date of registration: June 6 2018.

Tenecteplase versus Alteplase for Stroke Thrombolysis Evaluation Trial in the Ambulance (Mobile Stroke Unit-TASTE-A): protocol for a prospective randomised, open-label, blinded endpoint, phase II superiority trial of tenecteplase versus alteplase for ischaemic stroke patients presenting within 4.5 hours of symptom onset to the mobile stroke unit

INTRODUCTION

Mobile stroke units (MSUs) equipped with a CT scanner are increasingly being used to assess and treat stroke patients' prehospital with thrombolysis and transfer them to the most appropriate hospital for ongoing stroke care and thrombectomy when indicated. The effect of MSUs in both reducing the time to reperfusion treatment and improving patient outcomes is now established. There is now an opportunity to improve the efficacy of treatment provided by the MSU. Tenecteplase is a potent plasminogen activator, which may have benefits over the standard of care stroke lytic alteplase. Specifically, in the MSU environment tenecteplase presents practical benefits since it is given as a single bolus and does not require an infusion over an hour like alteplase.

OBJECTIVE

In this trial, we seek to investigate if tenecteplase, given to patients with acute ischaemic stroke as diagnosed on the MSU, improves the rate of early reperfusion.

METHODS AND ANALYSIS

TASTE-A is a prospective, randomised, open-label, blinded endpoint (PROBE) phase II trial of patients who had an ischaemic stroke assessed in an MSU within 4.5 hours of symptom onset. The primary endpoint is early reperfusion measured by the post-lysis volume of the CT perfusion lesion performed immediately after hospital arrival.

ETHICS AND DISSEMINATION

The study was approved by the Royal Melbourne Hospital Human Ethics committee. The findings will be published in peer-reviewed journals, presented at academic conferences and disseminated among consumer and healthcare professional audiences.

TRIAL REGISTRATION NUMBER

NCT04071613.

Advances in Acute Ischemic Stroke Therapy

The treatment of acute ischemic stroke continues to advance. The mainstay of treatment remains intravenous thrombolysis with alteplase. Recent studies demonstrated that later treatment with alteplase is beneficial in patients selected with advanced imaging techniques. Tenecteplase has been evaluated as an alternative thrombolytic drug and evidence suggests that it is as least as effective as alteplase and may lyse large vessel clots more effectively. Endovascular therapy with mechanical thrombectomy has now been shown to be beneficial up to 24 hours after stroke onset in carefully selected patients with proximal, large vessel occlusions. Ongoing studies are evaluating the effectiveness of thrombectomy in patients with more distal vessel occlusions and patients with proximal large vessel occlusions with larger ischemic core volumes and also in patients with milder neurological deficits. Cytoprotection is another potential acute stroke therapy that has not demonstrated efficacy in prior clinical trials. It should be reconsidered as an adjunct to reperfusion and a variety of new clinical trials can be envisioned to evaluate the potential benefits of cytoprotection in patients before and after reperfusion.

USPIO-SWI Shows Fingolimod Enhanced Alteplase Action on Angiographic Reperfusion in eMCAO Rats

BACKGROUND

Noninvasive evaluation of the status of cerebral arteriole perfusion remains a practical challenge in murine stroke models, because conventional magnetic resonance imaging (MRI) is no longer capable of capturing these very small vessels.

PURPOSE

To investigate the feasibility of ultrasmall superparamagnetic iron oxide particles (USPIO)-based susceptibility weighted imaging (SWI)-MRI (USPIO-SWI) and T2* map-MRI (USPIO-T2* map) for monitoring angiographic perfusion in stroke rats.

STUDY TYPE

A preclinical randomized controlled trial.

ANIMAL MODEL

Normal rats (N = 9), embolic middle cerebral artery occlusion (eMCAO) rats (N = 66).

FIELD STRENGTH/SEQUENCE

7 T; T2* map (multigradient echo), SWI (3D gradient echo).

ASSESSMENT

Experiment 1: To develop a method for angiographic reperfusion evaluation with USPIO-SWI. Normal rats were used to optimize the USPIO dosage (5.6, 16.8, and 56 mg/kg ferumoxytol) as well as scan time points for cerebral arterioles. Contrast-to-noise ratio (CNR) was measured. Stroke rats were further used and the number of visual cortical vessels were counted. Experiment 2: To examine whether fingolimod (lymphocytes inhibitor) enhances the action of tissue plasminogen activator (tPA) in eMCAO rats on cerebral angiographic reperfusion.

STATISTICAL TESTS

Mann-Whitney test and two way-ANOVA were used. P < 0.05 was considered statistically significant.

RESULTS

CNR values of cerebral cortical penetrating arteries in normal rats were significantly increased to 4.4 ± 0.5 (5.6 mg/kg), 6.1 ± 0.5 (16.8 mg/kg), and 3.4 ± 0.9 (56 mg/kg) after USPIO injection. The number of visual cortical vessels on USPIO-SWI images in ischemic regions was significantly less than in control regions (5 ± 2 vs. 56 ± 20) of eMCAO rats. Compared with eMCAO rats who received tPA only, eMCAO rats who received the combination of fingolimod and tPA exhibited significantly higher proportion of complete angiographic reperfusion (69% vs. 17%).

DATA CONCLUSION

This study supports the feasibility of angiographic perfusion evaluation with USPIO-SWI in stroke rats.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 1.

Off-Label Use of Tenecteplase for the Treatment of Acute Ischemic Stroke: A Systematic Review and Meta-analysis

IMPORTANCE

Tenecteplase is being evaluated as an alternative thrombolytic agent for the treatment of acute ischemic stroke (AIS) within ongoing randomized clinical trials (RCTs). In addition, nonrandomized clinical experiences with off-label use of tenecteplase vs alteplase for AIS treatment are being published.

OBJECTIVE

To evaluate the available evidence on the safety and efficacy of intravenous tenecteplase compared with intravenous alteplase provided by nonrandomized studies.

DATA SOURCES

Eligible studies were identified by searching MEDLINE and Scopus databases. No language or other restrictions were imposed. The literature search was conducted on October 12, 2021. This meta-analysis used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was written according to the Meta-analysis of Observational Studies in Epidemiology (MOOSE) proposal.

STUDY SELECTION

Nonrandomized studies (prospective or retrospective) comparing intravenous tenecteplase (at any dose) with intravenous alteplase in patients with AIS were included in the analysis.

DATA EXTRACTION AND SYNTHESIS

The crude odds ratios (ORs) and 95% CIs were calculated for the association of tenecteplase vs alteplase with the outcomes of interest and adjusted ORs were extracted if provided. Estimates using random-effects models were pooled.

MAIN OUTCOMES AND MEASURES

The primary outcome was the probability of good functional outcome (modified Rankin scale [mRS] score, 0-2) at 90 days.

RESULTS

Six studies were identified including a total of 1820 patients (618 [34%] treated with tenecteplase). Patients receiving tenecteplase had higher odds of 3-month good functional outcome (crude odds ratio [OR], 1.22; 95% CI, 0.90-1.66; adjusted OR, 1.60, 95% CI, 1.08-2.37), successful recanalization (crude OR, 2.82; 95% CI, 1.12-7.10; adjusted OR, 2.38; 95% CI, 1.18-4.81), and early neurological improvement (crude OR, 4.88; 95% CI, 2.03-11.71; adjusted OR, 7.60; 95% CI, 1.97-29.41). No significant differences were detected in 3-month excellent functional outcome proportions (mRS score 0-1; crude OR, 1.53; 95% CI, 0.81-2.91; adjusted OR, 2.51; 95% CI, 0.66- 9.49), symptomatic intracranial hemorrhage (crude OR, 0.97; 95% CI, 0.44-2.16; adjusted OR, 1.16; 95% CI, 0.13-10.50), or parenchymal hematoma (crude OR, 1.20; 95% CI, 0.24-5.95).

CONCLUSIONS AND RELEVANCE

Evidence from nonrandomized studies suggests tenecteplase is as safe as alteplase and potentially associated with improved functional outcomes compared with alteplase. Based on these findings, enrollment in the ongoing RCTs appears to be appropriate.

A fibrin targeted molecular imaging evaluation of microvascular no-reflow in acute ischemic stroke

OBJECTIVE

To investigate the relationship between fibrin deposition and "no-reflow" within microcirculation after thrombolysis in acute ischemic stroke (AIS).

MATERIALS AND METHODS

Experiments were approved by the institutional animal care and use committee. An experimental AIS model was induced in C57BL/6 mice by middle cerebral artery occlusion (MCAO) via the photothrombotic method. Mice were randomly assigned to non-thrombolytic or thrombolytic treated groups (n = 12 per group). The modified Neurological Severity Score and Fast Beam Balance Test were performed by a researcher blinded to the treatment method. MRI was utilized to evaluate all of the mice. An FXIIIa-targeted probe was applied to detect fibrin deposition in acute ischemic brain regions by fluorescence imaging. Necrosis and pathological changes of brain tissue were estimated via Hematoxylin and eosin staining while fibrin deposition was observed by immunohistochemistry.

RESULTS

Thrombolytic therapy improved AIS clinical symptoms. The infarct area of non-thrombolytic treated mice was significantly greater than that of the thrombolytic treated mice (p < .0001). Fluorescent imaging indicated fibrin deposition in ischemic brain tissue in both groups, with less fibrin in non-thrombolytic treated mice than thrombolytic treated mice, though the difference was not significant. Brain cells with abnormal morphology, necrosis, and liquefication were observed in the infarcted area for both groups. Clotted red blood cells (RBCs) and fibrin build-up in capillaries were found near the ischemic area in both non-thrombolytic and thrombolytic treated groups of mice.

CONCLUSION

Fibrin deposition and stacked RBCs contribute to microcirculation no-reflow in AIS after thrombolytic therapy.

A practice game changer: Impact of tenecteplase for acute ischemic stroke in a multicenter quality improvement project

PURPOSE

Tenecteplase is a thrombolytic that is more fibrin specific, has a longer half-life, and is easier to administer than alteplase for acute ischemic stroke (AIS). This article outlines the pharmacy experience and perspective on implementation of tenecteplase as the treatment of choice for AIS.

SUMMARY

Tenecteplase has been of increasing interest for AIS and is currently being studied in several clinical trials. Although it is not indicated by the Food and Drug Administration for AIS, several published studies and an update to stroke guidelines from the American Heart Association and American Stroke Association support its use in this setting. In January 2021, Cedars-Sinai Health System made the decision to add tenecteplase to the formulary for AIS in addition to keeping alteplase for patients who met the criterion of being outside the 4.5-hour window following stroke onset. Along with the added benefits of having tenecteplase on formulary come challenges of managing multiple thrombolytics for the same indication. Identifying key stakeholders and creating an interdisciplinary team are critical to ensure safe transitions.

CONCLUSION

Institutions can safely transition from alteplase to tenecteplase as a thrombolytic of choice for AIS.

Tenecteplase use in the management of acute ischemic stroke: Literature review and clinical considerations

DISCLAIMER

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

Several research articles have been published within the last decade comparing the use of tenecteplase to alteplase in ischemic stroke management. Prior reporting on the comparative therapeutic efficacy and safety profiles of tenecteplase and alteplase is reviewed.

SUMMARY

Tenecteplase is a variant of native tissue-type plasminogen activator, which rapidly promotes thrombolysis by catalyzing formation of the serine protease plasmin. Tenecteplase has theoretical advantages over alteplase as it has greater fibrin specificity and has a longer half-life than alteplase. This allows the administration of a single bolus over 5 to 10 seconds, as opposed to a bolus followed by a 1-hour infusion with alteplase. While currently approved by the Food and Drug Administration for the treatment of ST-segment elevation myocardial infarction, tenecteplase has also been studied in the treatment of acute ischemic stroke and has extensive data for this off-label indication. The most comprehensive trials to date evaluating the use of tenecteplase in acute ischemic stroke include the TNK-S2B, Australian TNK, ATTEST, Nor-Test, and EXTEND-IA TNK trials. Findings from these randomized controlled studies suggest that tenecteplase is at least as efficacious as alteplase in terms of neurological outcomes. The majority of these studies also reported a trend toward improved safety profiles with the use of tenecteplase.

CONCLUSION

Current clinical evidence shows that tenecteplase is not inferior to alteplase for the treatment of ischemic stroke and suggests that tenecteplase may have a superior safety profile. Furthermore, tenecteplase also has practical advantages in terms of its administration. This can potentially lead to a decrease in medication errors and improvement in door to thrombolytic time.

Tenecteplase vs. alteplase for acute ischemic stroke: a systematic review

INTRODUCTION

Thrombolysis for acute ischemic stroke (AIS) with alteplase is the currently approved therapy for patients who present within 4.5 h of symptom onset and meet criteria. Recently, there has been interest in the thrombolytic tenecteplase, a modified version of alteplase, due to its lower cost, ease of administration, and studies reporting better outcomes when compared to alteplase. This systematic review compares the efficacy of tenecteplase vs. alteplase with regard to three outcomes: (1) rate of symptomatic hemorrhage, (2) functional outcome at 90 days, and (3) reperfusion grade after thrombectomy to compare the efficacy of both thrombolytics in AIS METHODS: The search was conducted in August 2021 in PubMed, filtered for randomized controlled trials, and studies in English. The main search term was "tenecteplase for acute stroke."

RESULTS

A total of 6 randomized clinical trials including 1675 patients with AIS was included. No one's study compared alteplase to tenecteplase with all three outcomes after acute ischemic stroke; however, by using a combination of the results, this systematic review summarizes whether tenecteplase outperforms alteplase.

CONCLUSIONS

The available evidence suggests that tenecteplase appears to be a better thrombolytic agent for acute ischemic stroke when compared to alteplase.

Tenecteplase in Ischemic Stroke: Challenge and Opportunity

PURPOSE OF REVIEW

Intravenous thrombolysis is the first-line therapy for ischemic stroke, and alteplase has been used as an intravenous thrombolysis drug for over 20 years. However, considering its low rate of recanalization and risk of intracerebral hemorrhage, alteplase may not be the optimal thrombolytic drug of choice for ischemic stroke. Tenecteplase (TNK) is a genetically engineered, mutant, tissue plasminogen activator that is a potential substitute to alteplase in ischemic stroke. The pharmacokinetic advantages of TNK include greater fibrin selectivity than alteplase and prolonged half-life time. In this review, we have summarized the clinical trials of TNK in ischemic stroke.

RECENT FINDINGS

Clinical trials showed a higher recanalization rate of TNK over alteplase without increasing the rate of intracerebral hemorrhage. However, not all clinical trials showed superiority of TNK over alteplase in functional outcomes and early neurological improvement. TNK was superior to alteplase in terms of recanalization in patients who fulfilled the imaging mismatch criteria and in those planning to undergo mechanical thrombectomy.

SUMMARY

TNK has the potential to substitute alteplase for ischemic stroke therapy. Future TNK clinical trials that target functional outcomes are warranted.

Low-cost alternatives for the management of acute ischemic stroke in low and middle-income countries

Acute ischemic stroke (AIS) patients arriving within a suitable time frame are treated with recanalization therapy i.e. intravenous thrombolysis (IVT) with alteplase and/or mechanical thrombectomy (MT). IVT with alteplase is indicated in AIS patients presenting within 4.5 hours of onset regardless of vascular territory involved. MT is indicated in AIS patients presenting within 24 hours of onset with large vessel occlusion in the anterior circulation. However, MT is ludicrously expensive and requires exorbitant setup, devices, and expertise which is not currently feasible in LMICs. Therefore, in LMICs the only feasible recanalization option left for AIS patients is IVT. The cost of IVT varies across the LMICs, however, most of them cost around 2000-5000 USD. Apart from IVT, patients with AIS often have other significant medical costs including those for neuroimaging, intensive care, and prolonged rehabilitative treatment. In LMICs, these costs can only be afforded by a handful of patients. The majority of the LMICs have health insurance in their infancy and family members of AIS patients opt-out IVT due to the economic burden. In general, the current treatment guidelines for AIS are not very useful in LMICs because of cost-related issues among several other factors. In this editorial, we discuss evidence for alternative treatment strategies that can help tackle the rising epidemic of AIS in poor countries by improvising on existing clinical guidelines and seeking alternative treatment regimens.

Functional Outcome, Recanalization, and Hemorrhage Rates After Large Vessel Occlusion Stroke Treated With Tenecteplase Before Thrombectomy

BACKGROUND AND OBJECTIVES

To investigate in routine care the efficacy and safety of IV thrombolysis (IVT) with tenecteplase prior to mechanical thrombectomy (MT) in patients with large vessel occlusion acute ischemic strokes (LVO-AIS), either secondarily transferred after IVT or directly admitted to a comprehensive stroke center (CSC).

METHODS

We retrospectively analyzed clinical and procedural data of patients treated with 0.25 mg/kg tenecteplase within 270 minutes of LVO-AIS who underwent brain angiography. The main outcome was 3-month functional independence (modified Rankin Scale score ≤2). Recanalization (revised Treatment in Cerebral Ischemia score 2b-3) was evaluated before (pre-MT) and after MT (final).

RESULTS

We included 588 patients (median age 75 years [interquartile range (IQR) 61-84]; 315 women [54%]; median NIH Stroke Scale score 16 [IQR 10-20]), of whom 520 (88%) were secondarily transferred after IVT. Functional independence occurred in 47% (n = 269/570; 95% confidence interval [CI] 43.0-51.4) of patients. Pre-MT recanalization occurred in 120 patients (20.4%; 95% CI 17.2-23.9), at a similar rate across treatment paradigms (direct admission, n = 14/68 [20.6%]; secondary transfer, n = 106/520 [20.4%]; p > 0.99) despite a shorter median IVT to puncture time in directly admitted patients (38 [IQR 23-55] vs 86 [IQR 70-110] minutes; p < 0.001). Final recanalization was achieved in 492 patients (83.7%; 95%CI 80.4-86.6). Symptomatic intracerebral hemorrhage occurred in 2.5% of patients (n = 14/567; 95% CI 1.4-4.1).

DISCUSSIONS

Tenecteplase before MT is safe, effective, and achieves a fast recanalization in everyday practice in patients secondarily transferred or directly admitted to a CSC, in line with published results. These findings should encourage its wider use in bridging therapy.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that tenecteplase within 270 minutes of LVO-AIS increases the probability of functional independence.

Reflection on the Past, Present, and Future of Thrombolytic Therapy for Acute Ischemic Stroke

More than 25 years have passed since the US Food and Drug Administration approved IV recombinant tissue plasminogen activator (alteplase) for the treatment of acute ischemic stroke. This landmark decision brought a previously untreatable disease into a new therapeutic landscape, providing inspiration for clinicians and hope to patients. Since that time, the use of alteplase in the clinical setting has become standard of care, continually improving with quality measures such as door-to-needle times and other metrics of specialized stroke unit care. The past decade has seen more widespread use of alteplase in the prehospital setting with mobile stroke units and telestroke and beyond initial time windows via the use of CT perfusion or MRI. Simultaneously, the position of alteplase is being challenged by new lytics and by the concept of its bypass altogether in the era of endovascular therapy. We provide an overview of alteplase, including its earliest trials and how they have shaped the current therapeutic landscape of ischemic stroke treatment, and touch on new frontiers for thrombolytic therapy. We highlight the critical role of thrombolytic therapy in the past, present, and future of ischemic stroke care.

Imaging selection for reperfusion therapy in acute ischemic stroke beyond the conventional time window

Originally, the efficacy of acute ischemic stroke treatment with thrombolysis or thrombectomy was only proven in narrow time windows of, respectively, 4.5 and 6 h after onset. Introducing imaging-based selection beyond non-contrast enhanced computed tomography has expanded the treatment window, focusing on presumed tissue status rather than solely on time after stroke onset. Different mismatch concepts have been adopted in clinical practice to select patients in the extended and unknown time window based on findings from randomized controlled trials. Since various concepts exist that can identify patients likely to benefit from reperfusion strategies, clinicians may wonder which imaging modality may be preferred in the emergency setting. In this review, we will discuss the different mismatch concepts and their practical implementation for patient selection for thrombolysis or thrombectomy, beyond the conventional time window.

Sex differences in the Norwegian Tenecteplase Trial (NOR-TEST)

BACKGROUND AND PURPOSE

Sex differences in acute ischemic stroke is of increasing interest in the era of precision medicine. We aimed to explore sex disparities in baseline characteristics, management and outcomes in patients treated with intravenous thrombolysis included in the Norwegian Tenecteplase trial (NOR-TEST).

METHODS

NOR-TEST was an open-label, randomized, blinded endpoint trial, performed from 2012 to 2016, comparing treatment with tenecteplase to treatment with alteplase within 4.5 h after acute ischemic stroke symptom onset. Sex differences at baseline, treatment and outcomes were compared using multivariable logistic regression models. Heterogeneity in treatment was evaluated by including an interaction term in the model.

RESULTS

Of 1100 patients enrolled, 40% were women, and in patients aged >80 years, the proportion of women was greater than men (19% vs. 14%; p = 0.02). Women had a lower burden of cardiovascular risk factors, such as diabetes mellitus (11% vs. 15%; p = 0.05) and a higher mean high-density lipoprotein cholesterol level (1.7 ± 0.6 mmol/L vs. 1.3 ± 0.4 mmol/L; p < 0.001), and a higher proportion of women had never smoked (45% vs. 33%; p < 0.001) compared with men. While there was no sex difference in time from onset of symptoms to admission, door to needle time or in-hospital workup, women were admitted with more severe stroke (National Institutes of Health Stroke Scale [NIHSS] score 6.2 ± 5.6 vs. 5.3 ± 5.1; p = 0.01). Stroke mimic diagnosis was more common in women (21% vs. 15%; p = 0.01). There were no significant sex differences in clinical outcome, measured by the NIHSS, the modified Rankin Scale, intracranial hemorrhage and mortality.

CONCLUSION

Women were underrepresented in number in NOR-TEST. The included women had a lower cardiovascular risk factor burden and more severe strokes.

Comparison of Efficacy and Safety of Recombinant Human Prourokinase and Alteplase in the Treatment of STEMI and Analysis of Influencing Factors of Efficacy

OBJECTIVE

To compare the efficacy and safety of recombinant human prourokinase (rhPro-UK) and alteplase for thrombolytic therapy in acute ST-segment elevation myocardial infarction (STEMI) and to analyze the related factors affecting efficacy.

METHODS

From January 2017 to December 2019, 100 patients diagnosed with STEMI were selected and randomly divided into the control group (n = 50) and the observation group (n = 50). Based on conventional treatments, the control group was treated with alteplase, and the observation group was treated with rhPro-UK, and both were treated for 7 days. After treatment, the vascular recanalization, left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic diameter (LVEDD), and left ventricular ejection fraction (LVEF) were compared. The bleeding and major adverse cardiovascular events (MACE) were recorded in both groups. According to the patient's vascular recanalization, it was divided into two subgroups: recanalization group and occlusion group. Multiple logistic regression models were used to analyze the related factors that affect the efficacy.

RESULTS

The recanalization rate of the observation group (96.00%) was higher than that of the control group (84.00%) (P < 0.05). After treatment, LVDs and LVEDD in both groups were lower than those before treatment, and LVEF was higher than that before treatment. The LVDs and LVEDD in the observation group were lower than those in the control group, and the LVEF was higher than that in the control group (P < 0.05). The incidence of bleeding in the observation group (2.00%) was lower than that in the control group (12.00%), and the incidence of MACE (4.00%) was lower than that in the control group (16.00%) (P < 0.05). Univariate analysis showed that age, smoking history, diabetes history, myocardial infarction history, infarct location, and intravenous thrombolysis time were related to the efficacy after treatment (P < 0.05). Multivariate logistic analysis showed that age, history of diabetes, vascular infarction site, and venous thrombolysis time were independent influencing factors after treatment (P < 0.05).

CONCLUSION

Both rhPro-UK and alteplase thrombolytic therapy can effectively recanalize blood vessels and improve the cardiac function of patients with STEMI. However, rhPro-UK has better effect than alteplase and is safer and worth promoting. The curative effect is related to age, diabetes history, vascular infarction site, and venous thrombolysis time.

Adapting Clinical Practice of Thrombolysis for Acute Ischemic Stroke Beyond 4.5 Hours: A Review of the Literature

Several clinical trials have demonstrated that advanced neuroimaging can select patients for recanalization therapy in an extended time window. The favorable functional outcomes and safety profile of these studies have led to the incorporation of neuroimaging in endovascular treatment guidelines, and most recently, also extended to decision making on thrombolysis. Two randomized clinical trials have demonstrated that patients who are not amenable to endovascular thrombectomy within 4.5 hours from symptoms discovery or beyond 4.5 hours from the last-known-well time may also be safely treated with intravenous thrombolysis and have a clinical benefit above the risk of safety concerns. With the growing aging population, increased stroke incidence in the young, and the impact of evolving medical practice, healthcare and stroke systems of care need to adapt continuously to provide evidence-based care efficiently. Therefore, understanding and incorporating appropriate screening strategies is critical for the prompt recognition of potentially eligible patients for extended-window intravenous thrombolysis. Here we review the clinical trial evidence for thrombolysis for acute ischemic stroke in the extended time window and provide a review of new enrolling clinical trials that include thrombolysis intervention beyond the 4.5 hour window.

Tenecteplase Reperfusion therapy in Acute ischaemic Cerebrovascular Events-II (TRACE II): rationale and design

BACKGROUND AND PURPOSE

Tenecteplase (TNK) is a promising agent for treatment of acute ischaemic stroke (AIS). We hypothesised that recombinant human TNK tissue-type plasminogen activator (rhTNK-tPA) is non-inferior to rt-PA in achieving excellent functional outcome at 90 days, when administered within 4.5 hours of ischaemic stroke onset.

METHODS AND DESIGN

Tenecteplase Reperfusion therapy in Acute ischemic Cerebrovascular Events (TRACE) is a phase III, multicentre, prospective, randomised, open-label, blinded-end point non-inferiority study. Patients eligible for intravenous thrombolysis therapy are randomised to rhTNK-tPA 0.25 mg/kg (single bolus) to a maximum of 25 mg or rt-PA 0.9 mg/kg (10% bolus+90% infusion/1 hour) to a maximum of 90 mg. Medications considered necessary for the patient's health may be given at the discretion of the investigator during 90-day follow-up.

STUDY OUTCOMES

The primary study outcome is excellent functional outcome defined as modified Rankin Scale (mRS) 0-1 at 90 days. Secondary efficacy outcomes include favourable functional outcome defined as mRS ≤2 at 90 days, ordinal distribution of mRS and major neurological improvement on the National Institutes of Health Stroke Scale. Safety outcomes are symptomatic intracranial haemorrhage within 36 hours and death from any cause.

DISCUSSION

There is no completed registration study of TNK in AIS worldwide. TRACE II strives to provide evidence for a new drug application for rhTNK-tPA in AIS within 4.5 hours through a well-designed and rigorously executed randomised trial in China.

TRIAL REGISTRATION NUMBER

NCT04797013.

Safety and efficacy of tenecteplase versus alteplase in patients with acute ischaemic stroke (TRACE): a multicentre, randomised, open label, blinded-endpoint (PROBE) controlled phase II study

Background

Tenecteplase (TNK) possesses several pharmacological characteristics superior to conventional alteplase (rt-PA), with well-established safety and efficacy profile in Caucasians. There exists controversy over the optimal dose of intravenous rt-PA for East Asians with acute ischaemic stroke (AIS). Current study aimed to determine the safety dose range of recombinant human TNK tissue-type plasminogen activator (rhTNK-tPA) for patients with AIS in China.

Methods

This multicentre, prospective, randomised, open-label, blinded end-point, phase II study compared three tiers of 0.1, 0.25, 0.32 mg/kg rhTNK-tPA (to a maximum of 40 mg) with standard 0.9 mg/kg rt-PA (to a maximum of 90 mg) in patients who were eligible for intravenous thrombolysis. The safety outcome were symptomatic intracranial haemorrhage (sICH) within 36 hours.

Results

Between May 2018 and February 2020, 240 patients were randomly assigned to four group, 4 of whom did not receive study treatment. The intention-to-treat analysis included 236 patients. There was no difference in the improvement on National Institutes of Health Stroke Scale at day 14 in the 3 tiers and control group (63.3%, 77.2%, 66.7% vs 62.7%). The number of sICH was 3 of 60 (5.0%) in the 0.1 mg/kg group, none in the 0.25 mg/kg group, 2 of 60 (3.3%) in the 0.32 mg/kg group and 1 (1.7%) of 59 in the rt-PA group. There were no significant between-group differences in severe adverse events.

Conclusions

Similar to the Caucasians, rhTNK-tPA was well tolerated in Chinese patients with AIS at all doses administered within 3 hours of symptom onset. The dose-efficacy profile of rhTNK-tPA needs to be established with future investigations.

Trial registration number

NCT04676659.

Tenecteplase Thrombolysis in Posterior Circulation Stroke

One in five ischaemic strokes affects the posterior circulation. Basilar artery occlusion is a type of posterior circulation stroke associated with a high risk of disability and mortality. Despite its proven efficacy in ischaemic stroke more generally, alteplase only achieves rapid reperfusion in ~4% of basilar artery occlusion patients. Tenecteplase is a genetically modified variant of alteplase with greater fibrin specificity and longer half-life than alteplase, which can be administered by intravenous bolus. The single-bolus administration of tenecteplase vs. an hour-long alteplase infusion is a major practical advantage, particularly in "drip and ship" patients with basilar artery occlusion who are being transported between hospitals. Other practical advantages include its reduced cost compared to alteplase. The EXTEND-IA TNK trial demonstrated that tenecteplase led to higher reperfusion rates prior to endovascular therapy (22 vs. 10%, non-inferiority p = 0.002, superiority p = 0.03) and improved functional outcomes (ordinal analysis of the modified Rankin Scale, common odds ratio 1.7, 95% CI 1.0-2.8, p = 0.04) compared with alteplase in large-vessel occlusion ischaemic strokes. We recently demonstrated in observational data that tenecteplase was associated with increased reperfusion rates compared to alteplase prior to endovascular therapy in basilar artery occlusion [26% (n = 5/19) of patients thrombolysed with TNK vs. 7% (n = 6/91) thrombolysed with alteplase (RR 4.0 95% CI 1.3-12; p = 0.02)]. Although randomized controlled trials are needed to confirm these results, tenecteplase can be considered as an alternative to alteplase in patients with basilar artery occlusion, particularly in "drip and ship" patients.

Comparison of thrombolytic agents in treatment of patients with acute ischemic stroke; findings from a single centre follow up study in real-life settings

BACKGROUND AND OBJECTIVES

Health outcome data of thrombolysis in patients with acute ischemic stroke in real life-settings in India are scarce. We studied the clinical profile, risk factors and functional outcome of patients with acute ischemic stroke (AIS) who were thrombolysed.

METHODS

In a single centre retrospective study from January 2017 to June 2020, we analysed the data of adult patients with AIS presented within 4.5 h of symptom onset. We included patients if they had NIHSS score ≥4, modified Rankin score of 2 or less before the stroke onset and without evidence of haemorrhage. Modified Rankin score of two or less at the end of three months was defined as the primary efficacy outcome. The development of symptomatic intracerebral haemorrhage was considered as the primary safety outcome. We tried to analyse the primary safety and efficacy outcomes between two thrombolytic agents.

RESULTS

Ninety patients (Tenecteplase = 61; Alteplase, n = 29) underwent stroke thrombolysis during the study period. The mean age was 64.3 years in Tenecteplase group and 63.2 years in Alteplase group. Twenty patients were aged more than 75 years. Hypertension was the most common comorbidity in both the groups (72% and 72.4%). Median mRS score at 3-months was 1 in Tenecteplase group and 0.5 in Alteplase group (p < 0.001), however there was no statistically significant difference between both treatment groups in terms of NIHS score at 24 h (70.4% vs 51.7%, p = 0.08), functional recovery calculated with mRS at 3-month (83.6% vs 79.3%, p = 0.62) or in terms of symptomatic ICH (9.8% and 17.2% p = 0.36).

CONCLUSION

Tenecteplase appears to have similar clinical outcomes as Alteplase for stroke thrombolysis. Given the relatively low-cost and ease of administration, Tenecteplase may be better than Alteplase for management of acute ischemic stroke.

Sex Disparities in Enrollment in Recent Randomized Clinical Trials of Acute Stroke: A Meta-analysis

Importance

The underenrollment of women in randomized clinical trials represents a threat to the validity of the evidence supporting clinical guidelines and potential disparities in access to novel treatments.

Objective

To determine whether women were underenrolled in contemporary randomized clinical trials of acute stroke therapies published in 9 major journals after accounting for their representation in underlying stroke populations.

Data Sources

MEDLINE was searched for acute stroke therapeutic trials published between January 1, 2010, and June 11, 2020.

Study Selection

Eligible articles reported the results of a phase 2 or 3 randomized clinical trial that enrolled patients with stroke and/or transient ischemic attack and examined a therapeutic intervention initiated within 1 month of onset.

Data Extraction

Data extraction was performed by 2 independent authors in duplicate. Individual trials were matched to estimates of the proportion of women in underlying stroke populations using the Global Burden of Disease database.

Main Outcomes and Measures

The primary outcome was the enrollment disparity difference (EDD), the absolute difference between the proportion of trial participants who were women and the proportion of strokes in the underlying disease populations that occurred in women. Random-effects meta-analyses of the EDD were performed, and multivariable metaregression was used to explore the associations of trial eligibility criteria with disparity estimates.

Results

The search returned 1529 results, and 115 trials (7.5%) met inclusion criteria. Of 121 105 randomized patients for whom sex was reported, 52 522 (43.4%) were women. The random-effects summary EDD was -0.053 (95% CI, -0.065 to -0.040), indicating that women were underenrolled by 5.3 percentage points. This disparity persisted across virtually all geographic regions, intervention types, and stroke types, apart from subarachnoid hemorrhage (0.117 [95% CI, 0.084 to 0.150]). When subarachnoid hemorrhage trials were excluded, the summary EDD was -0.067 (95% CI, -0.078 to -0.057). In the multivariable metaregression analysis, an upper age limit of 80 years as an eligibility criterion was associated with a 6-percentage point decrease in the enrollment of women.

Conclusions and Relevance

Further research is needed to understand the causes of the underenrollment of women in acute stroke trials. However, to maximize representation, investigators should avoid imposing age limits on enrollment.