Combined approach to lysis utilizing eptifibatide and recombinant tissue plasminogen activator in acute ischemic stroke-enhanced regimen stroke trial

Safety and efficacy of platelet glycoprotein VI inhibition in acute ischaemic stroke (ACTIMIS): a randomised, double-blind, placebo-controlled, phase 1b/2a trial

BACKGROUND

Antagonists of glycoprotein VI-triggered platelet activation used in combination with recanalisation therapies are a promising therapeutic approach in acute ischaemic stroke. Glenzocimab is an antibody fragment that inhibits the action of platelet glycoprotein VI. We aimed to determine and assess the safety and efficacy of the optimal dose of glenzocimab in patients with acute ischaemic stroke eligible to receive alteplase with or without mechanical thrombectomy.

METHODS

This randomised, double-blind, placebo-controlled study with dose-escalation (1b) and dose-confirmation (2a) phases (ACTIMIS) was done in 26 stroke centres in six European countries. Participants were adults (≥18 years) with disabling acute ischaemic stroke with a National Institutes of Health Stroke Scale score of 6 or higher before alteplase administration. Patients were randomly assigned treatment using a central electronic procedure. Total administered dose at the end of the intravenous administration was 125 mg, 250 mg, 500 mg, and 1000 mg of glenzocimab or placebo in phase 1b and 1000 mg of glenzocimab or placebo in phase 2a. Treatment was initiated 4·5 h or earlier from stroke symptom onset in patients treated with alteplase with or without mechanical thrombectomy. The sponsor, study investigator and study staff, patients, and central laboratories were all masked to study treatment until database lock. Primary endpoints across both phases were safety, mortality, and intracranial haemorrhage (symptomatic, total, and fatal), assessed in all patients who received at least a partial dose of study medication (safety set). The trial is registered on ClinicalTrials.gov, NCT03803007, and is complete.

FINDINGS

Between March 6, 2019, and June 27, 2021, 60 recruited patients were randomly assigned to 125 mg, 250 mg, 500 mg, or 1000 mg glenzocimab, or to placebo in phase 1b (n=12 per group) and were included in the safety analysis. Glenzocimab 1000 mg was well tolerated and selected as the phase 2a recommended dose; from Oct 2, 2020, to June 27, 2021, 106 patients were randomly assigned to glenzocimab 1000 mg (n=53) or placebo (n=53). One patient in the placebo group received glenzocimab in error and therefore 54 and 52, respectively, were included in the safety set. In phase 2a, the most frequent treatment-emergent adverse event was non-symptomatic haemorrhagic transformation, which occurred in 17 (31%) of 54 patients treated with glenzocimab and 26 (50%) of 52 patients treated with placebo. Symptomatic intracranial haemorrhage occurred in no patients treated with glenzocimab compared with five (10%) patients in the placebo group. All-cause deaths were lower with glenzocimab 1000 mg (four [7%] patients) than with placebo (11 [21%] patients).

INTERPRETATION

Glenzocimab 1000 mg in addition to alteplase, with or without mechanical thrombectomy, was well tolerated, and might reduce serious adverse events, intracranial haemorrhage, and mortality. These findings support the need for future research into the potential therapeutic inhibition of glycoprotein VI with glenzocimab plus alteplase in patients with acute ischaemic stroke.

FUNDING

Acticor Biotech.

Tenecteplase Treatment and Thrombus Characteristics Associated With Early Reperfusion: An EXTEND-IA TNK Trials Analysis

BACKGROUND

Intracranial occlusion site, contrast permeability, and clot burden are thrombus characteristics that influence alteplase-associated reperfusion. In this study, we assessed the reperfusion efficacy of tenecteplase and alteplase in subgroups based on these characteristics in a pooled analysis of the EXTEND-IA TNK trial (Tenecteplase Versus Alteplase Before Endovascular Therapy for Ischemic Stroke).

METHODS

Patients with large vessel occlusion were randomized to treatment with tenecteplase (0.25 or 0.4 mg/kg) or alteplase before thrombectomy in hospitals across Australia and New Zealand (2015-2019). The primary outcome, early reperfusion, was defined as the absence of retrievable thrombus or >50% reperfusion on first-pass angiogram. We compared the effect of tenecteplase versus alteplase overall, and in subgroups, based on the following measured with computed tomography angiography: intracranial occlusion site, contrast permeability (measured via residual flow grades), and clot burden (measured via clot burden scores). We adjusted for covariates using mixed effects logistic regression models.

RESULTS

Tenecteplase was associated with higher odds of early reperfusion (75/369 [20%] versus alteplase: 9/96 [9%], adjusted odds ratio [aOR], 2.18 [95% CI, 1.03-4.63]). The difference between thrombolytics was notable in occlusions with low clot burden (tenecteplase: 66/261 [25%] versus alteplase: 5/67 [7%], aOR, 3.93 [95% CI, 1.50-10.33]) when compared to high clot burden lesions (tenecteplase: 9/108 [8%] versus alteplase: 4/29 [14%], aOR, 0.58 [95% CI, 0.16-2.06]; P_interaction=0.01). We did not observe an association between contrast permeability and tenecteplase treatment effect (permeability present: aOR, 2.83 [95% CI, 1.00-8.05] versus absent: aOR, 1.98 [95% CI, 0.65-6.03]; P_interaction=0.62). Tenecteplase treatment effect was superior with distal M1 or M2 occlusions (53/176 [30%] versus alteplase: 4/42 [10%], aOR, 3.73 [95% CI, 1.25-11.11]), but both thrombolytics had limited efficacy with internal carotid artery occlusions (tenecteplase 1/73 [1%] versus alteplase 1/19 [5%], aOR, 0.22 [95% CI, 0.01-3.83]; P_interaction=0.16).

CONCLUSIONS

Tenecteplase demonstrates superior early reperfusion versus alteplase in lesions with low clot burden. Reperfusion efficacy remains limited in internal carotid artery occlusions and lesions with high clot burden. Further innovation in thrombolytic therapies are required.

Pharmacological Strategies for Stroke Intervention: Assessment of Pathophysiological Relevance and Clinical Trials

OBJECTIVES

The present review describes stroke pathophysiology in brief and discusses the spectrum of available treatments with different promising interventions that are in clinical settings or are in clinical trials.

METHODS

Relevant articles were searched using Google Scholar, Cochrane Library, and PubMed. Keywords for the search included ischemic stroke, mechanisms, stroke interventions, clinical trials, and stem cell therapy.

RESULTS AND CONCLUSION

Stroke accounts to a high burden of mortality and morbidity around the globe. Time is an important factor in treating stroke. Treatment options are limited; however, agents with considerable efficacy and tolerability are being continuously explored. With the advances in stroke interventions, new therapies are being formulated with a hope that these may aid the ongoing protective and reparative processes. Such therapies may have an extended therapeutic time window in hours, days, weeks, or longer and may have the advantage to be accessible by a majority of the patients.

Eptifibatide use in ischemic stroke patients undergoing endovascular thrombectomy: A matched cohort analysis

Introduction

Small studies have suggested that eptifibatide (EPT) may be safe in acute ischemic stroke (AIS) following intravenous thrombolysis or during endovascular therapy (EVT) for large vessel occlusion (LVO). However, studies are called upon to better delineate the safety of EPT use during EVT.

Methods

A comprehensive stroke center registry (09/2015-12/2020) of consecutive adults who had undergone EVT for anterior LVO was queried. Patients treated with EPT were matched with 2 control groups based on known factors associated with intracranial hemorrhage (ICH) risk - age, Alberta Stroke Program Early Computed Tomography Score (ASPECTS), and number of thrombectomy passes. Safety outcomes (intracranial hemorrhage [ICH], parenchymal hematoma [PH-2] grade hemorrhagic transformation, symptomatic ICH [sICH]) and efficacy outcomes (TICI 2B/3 recanalization, 24-h National Institutes of Health Stroke Scale [NIHSS] score), were compared between matched groups using descriptive statistics. In addition, multivariable logistic regression was used to assess for an association between EPT and PH-1/PH-2 grade hemorrhages.

Results

A total of 162 patients were included, 54 of whom (33%) received EPT. The rate of ICH was similar between groups (p = 0.62), while PH-2 was significantly more frequent with EPT (16.7% EPT vs. 3.7 vs. 1.9%; p = 0.009), but without significant differences in sICH (5.6% EPT vs. 7.4 vs. 3.7%; p = 0.72). Rates of TICI Score ≥ 2B were nominally higher with EPT use (83.3 vs. 77.8 vs. 77.8%, p = 0.70). Between the EPT and control groups, there were no differences in 24-h NIHSS (p = 0.09) or 90-day mortality (p = 0.58). Our adjusted multivariate analysis identified that the number of passes (p < 0.01), EPT use (p < 0.01), and tandem occlusion (p = 0.03) were independent predictors of PH1/PH2 grade hemorrhage. Additionally, every unit increase in number of passes resulted in a 1.5 times greater odds of a high-grade hemorrhagic transformation in EPT-treated patients (adjusted OR = 1.594).

Conclusion

In this single-center analysis, EPT use during EVT was associated with a significantly higher rate of PH1/PH2 grade hemorrhages, but not with differences in sICH, 24-h NIHSS, or 90-day mortality. Randomized prospective trials are needed to determine the safety and efficacy of EPT in this population.

Investigational drugs for ischemic stroke: what's in the clinical development pipeline for acute phase and prevention?

INTRODUCTION

Stroke is a leading cause of disability and mortality and its burden expected to increase. The only approved drug for acute ischemic stroke is the intravenous thrombolytic alteplase. The risk of bleeding complications is one of the reasons for the undertreatment of eligible patients. Numerous drugs are currently being developed to improve safety-efficacy.

AREAS COVERED

We reviewed literature from January 1^st, 2000, to 15^th January 2022 for the development and testing of novel drugs with the aim of targeting treatment at prevention of ischemic stroke: PubMed, MEDLINE, Google Scholar, and ClinicalTrial.gov.

EXPERT OPINION

The pathophysiology of ischemic stroke involves multiple pathways causing cerebral artery obstruction and brain tissue ischemia. Data suggest that tenecteplase is a more promising fibrinolytic agent with a superior efficacy-safety profile, compared to the currently approved alteplase. Current guidelines consider a short-term cycle of mannitol or hypertonic saline to be advisable in patients with space-occupying hemispheric infarction. Regarding primary and secondary prevention, research is primarily focused on identifying mechanisms to improve the safety-efficacy profile using a "hemostasis-sparing" approach. Further evaluation on those agents that have already shown promise for their risk/benefit profiles, would benefit greatly a neurologist's capacity to successfully prevent and treat ischemic stroke patients.

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.

Combined Approach to Eptifibatide and Thrombectomy in Acute Ischemic Stroke Because of Large Vessel Occlusion: A Matched-Control Analysis

BACKGROUND

In patients undergoing mechanical thrombectomy (MT), adjunctive antithrombotic might improve angiographic reperfusion, reduce the risk of distal emboli and reocclusion but possibly expose patients to a higher intracranial hemorrhage risk. This study evaluated the safety and efficacy of combined MT plus eptifibatide for acute ischemic stroke.

METHODS

This was a propensity-matched analysis of data from 2 prospective trials in Chinese populations: the ANGEL-ACT trial (Endovascular Treatment Key Technique and Emergency Workflow Improvement of Acute Ischemic Stroke) in 111 hospitals between November 2017 and March 2019, and the EPOCH trial (Eptifibatide in Endovascular Treatment of Acute Ischemic Stroke) in 15 hospitals between April 2019 and March 2020. The primary efficacy outcome was good outcome (modified Rankin Scale score 0-2) at 3 months. Secondary efficacy outcomes included the distribution of 3-month modified Rankin Scale scores and poor outcome (modified Rankin Scale score 5-6) and successful recanalization. The safety outcomes included any intracranial hemorrhage, symptomatic intracranial hemorrhage, and 3-month mortality. Mixed-effects logistic regression models were used to account for within-hospital clustering in adjusted analyses.

RESULTS

Eighty-one combination arm EPOCH subjects were matched with 81 ANGEL-ACT noneptifibatide patients. Compared with the no eptifibatide group, the eptifibatide group had significantly higher rates of successful recanalization (91.3% versus 81.5%; P=0.043) and 3-month good outcomes (53.1% versus 33.3%; P=0.016). No significant difference was found in the remaining outcome measures between the 2 groups. All outcome measures of propensity score matching were consistent with mixed-effects logistic regression models in the total population.

CONCLUSIONS

This matched-control study demonstrated that MT combined with eptifibatide did not raise major safety concerns and showed a trend of better efficacy outcomes compared with MT alone. Overall, eptifibatide shows potential as a periprocedural adjunctive antithrombotic therapy when combined with MT. Further randomized controlled trials of MT plus eptifibatide should be prioritized.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03844594 (EPOCH), NCT03370939 (ANGEL-ACT).

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.

Repeated Intravenous Thrombolysis in Patients with Recurrent Ischemic Stroke in the Vertebrobasilar Territory

Acute ischemic vertebrobasilar stroke (AIVBS) is usually associated with poor outcome and prognosis and in case of basilar artery occlusion (BAO) with high mortality. Intravenous thrombolysis (IVT), as a standard recanalization therapy of acute ischemic stroke (IS) within first 4.5 h, can be administrated beyond this therapeutic time window in case of symptomatic BAO. Repeated IVT is generally contraindicated in case of early recurrent IS, despite a risk of poor outcome or death after recurrent IS. The aim was to present 2 cases of repeated IVT for recurrent AIVBS and discuss specific situations where repeated IVT may be considered. Up to now, repeated IVT has been reported only in recurrent stroke in anterior circulation.

The safety and effectiveness of early anti-platelet therapy after alteplase for acute ischemic stroke: A meta-analysis

BACKGROUND

For acute ischemic stroke patients, there is a risk of reocclusion after intravenous thrombolysis. In theory, early anti-platelet therapy can reduce the risk of vessel reocclusion. Although current guidelines do not recommend routine anti-platelet therapy within 24 h of intravenous thrombolytic therapy, many studies disagreed with it, especially after the emergence of new anti-platelet drugs. It is necessary to conduct a meta-analysis based on high-quality randomized controlled studies to re-evaluate this treatment strategy.

METHODS

Literature retrieval was systematically conducted in PubMed, Embase, Cochrane, Web of sicence, clinical trials, CNKI and Wanfang Data, for searching randomized controlled trials (published between January 1, 2000 and April 30, 2020 with no language restrictions) comparing early (within 24 h) with routine (after 24 h) anti-platelet-aggregation therapy after rt-PA intravenous thrombolysis. The primary safety endpoint and primary efficacy indicator are the incidence of symptomatic intracranial hemorrhage and a good prognosis at 90-day (modified Rankin Scale (mRS) score of 0-1 or return to baseline mRS), respectively. We assessed pooled data by use of a random-effects model.

FINDINGS

Of the 378 identified studies, only 3 were eligible and included in our analysis (N = 1008 participants). Compared with routine treatment, early anti-platelet-aggregation therapy after rt-PA intravenous thrombolysis in acute ischemic stroke patients did not affect the 90-day efficacy (95% CI 0.97 - 1.32). In terms of safety assessment, the early use of anti-platelet-aggregation drugs after thrombolysis has a neutral effect on the risk of intracranial hemorrhage, symptomatic intracranial hemorrhage, and bleeding from other systemic sites.

CONCLUSION

Early anti-platelet therapy after alteplase did not benefit the acute ischemic stroke patients based on the current evidence. However, more clinical trials and statistical evidence are still needed.

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.

European Stroke Organisation (ESO) guidelines on intravenous thrombolysis for acute ischaemic stroke

Intravenous thrombolysis is the only approved systemic reperfusion treatment for patients with acute ischaemic stroke. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist physicians in their clinical decisions with regard to intravenous thrombolysis for acute ischaemic stroke. These guidelines were developed based on the ESO standard operating procedure and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and wrote recommendations. Expert consensus statements were provided if not enough evidence was available to provide recommendations based on the GRADE approach. We found high quality evidence to recommend intravenous thrombolysis with alteplase to improve functional outcome in patients with acute ischemic stroke within 4.5 h after symptom onset. We also found high quality evidence to recommend intravenous thrombolysis with alteplase in patients with acute ischaemic stroke on awakening from sleep, who were last seen well more than 4.5 h earlier, who have MRI DWI-FLAIR mismatch, and for whom mechanical thrombectomy is not planned. These guidelines provide further recommendations regarding patient subgroups, late time windows, imaging selection strategies, relative and absolute contraindications to alteplase, and tenecteplase. Intravenous thrombolysis remains a cornerstone of acute stroke management. Appropriate patient selection and timely treatment are crucial. Further randomized controlled clinical trials are needed to inform clinical decision-making with regard to tenecteplase and the use of intravenous thrombolysis before mechanical thrombectomy in patients with large vessel occlusion.

Alteplase and Adjuvant Therapies for Acute Ischemic Stroke

Acute ischemic stroke (AIS) is a time sensitive medical emergency and a leading cause of morbidity and mortality worldwide. Intravenous (IV) recombinant tissue plasminogen activator (IV alteplase) is currently the only proven effective medication for the treatment of AIS with promising adjuvant medications currently under investigation. Recent advances in endovascular thrombectomy have broadened therapeutic options in specific patient populations, with modern treatment strategies utilizing advanced imaging modalities to extend the window for treatment. In all cases, rapid treatment remains a priority. The future of IV alteplase and the changing standard for treatment of AIS remain unwritten with the increasing evidence for imaging selection for both endovascular thrombectomy and IV alteplase, while novel adjuncts are under investigation. In this article, we review the history of IV alteplase investigations for stroke, evidence for thrombectomy as an adjunct to IV alteplase, and the potential of novel adjuvant therapeutics currently under investigation.

Stroke Thrombolysis in Patients Taking Ticagrelor -Two Successful Cases and a Review of the Literature

BACKGROUND

Ticagrelor is a novel antiplatelet agent that is frequently used for secondary prevention in coronary artery disease and has emerging evidence in stroke after the recent results of SOCRATES and THALES trials. The use of intravenous thrombolysis with alteplase in acute ischemic stroke (AIS) patients on ticagrelor is a topic of debate as the safety profile of ticagrelor in this setting is not well established.

METHODS

We identified consecutive AIS patients taking ticagrelor who received intravenous alteplase at a comprehensive stroke center from January 2016 to December 2019. We then performed a literature search to capture all known published cases of intravenous thrombolysis in stroke patients on ticagrelor.

RESULTS

Of the 3896 patients who were treated for AIS at our local comprehensive stroke center during this time period, two patients received intravenous alteplase while on ticagrelor. Both patients had posterior circulation acute strokes and were successfully treated with intravenous alteplase without a systemic or intracranial bleeding event. Only five other cases of intravenous thrombolysis in AIS patients on ticagrelor have been reported in the literature. Among these cases, four of the five cases had a hemorrhagic complication.

CONCLUSION

Despite prior reports of hemorrhagic complications with use of IV alteplase in setting of pre-treatment with ticagrelor, we report the safe use of intravenous thrombolysis in two cases presenting with acute ischemic stroke. Until safety is established in large studies, decision for thrombolysis should be made on case-by-case basis.

The multiarm optimization of stroke thrombolysis phase 3 acute stroke randomized clinical trial: Rationale and methods

BACKGROUND

Intravenous recombinant tissue plasminogen activator is the only proven effective medication for the treatment of acute ischemic stroke. Two approaches that may augment recombinant tissue plasminogen activator thrombolysis and prevent arterial reocclusion are direct thrombin inhibition with argatroban and inhibition of the glycoprotein 2b/3a receptor with eptifibatide.

AIM

The multi-arm optimization of stroke thrombolysis trial aims to determine the safety and efficacy of intravenous therapy with argatroban or eptifibatide as compared with placebo in acute ischemic stroke patients treated with intravenous recombinant tissue plasminogen activator within 3 h of symptom onset.

SAMPLE SIZE ESTIMATE

A maximum of 1200 randomized subjects to test the superiority of argatroban or eptifibatide to placebo in improving 90-day modified Rankin scores.

METHODS AND DESIGN

Multiarm optimization of stroke thrombolysis is a multicenter, multiarm, adaptive, single blind, randomized controlled phase 3 clinical trial conducted within the National Institutes of Health StrokeNet clinical trial network. Patients treated with 0.9 mg/kg intravenous recombinant tissue plasminogen activator within 3 h of stroke symptom onset are randomized to receive intravenous argatroban (100 µg/kg bolus followed by 3 µg/kg/min for 12 h), intravenous eptifibatide (135 µg/kg bolus followed by 0.75 µg/kg/min infusion for 2 h) or IV placebo. Patients may receive endovascular thrombectomy per usual care.

STUDY OUTCOMES

The primary efficacy outcome is improved modified Rankin score assessed at 90 days post-randomization.

DISCUSSION

Multiarm optimization of stroke thrombolysis is an innovative and collaborative project that is the culmination of many years of dedicated efforts to improve outcomes for stroke patients.

Effects of two different glycoprotein platelet IIb/IIIa inhibitors and the clinical endpoints in patients with intracranial Pipeline flow diverter implant

Objective

To compare the antiplatelet effect and major adverse cerebrovascular events of Pipeline for intracranial aneurysms using glycoprotein IIb/IIIa antagonists (GPI) eptifibatide and tirofiban.

Methods

Retrospective analysis of relevant data of patients using GPIs combined with oral antiplatelet therapy in Nanfang Hospital of Southern Medical University from December 2017 to December 2019. The study was approved by the ethics Committee of Nanfang Hospital of Southern Medical University. According to the random use of GPIs drugs, they were assigned to the eptifibatide group and tirofiban group. Basic data, platelet inhibition rates at baseline, 24h and 72h after administration, short-term major adverse cerebrovascular events, and bleeding complications were compared between the two groups.

Results

A total of 47 patients were included in this study, including 24 patients in eptifibatide group and 23 patients in tirofiban group. There was no significant difference in average age (53.75 vs. 53.91 years) and body mass index (BMI) (24.39 vs. 22.73 ​kg/m2) between eptifibatide group and tirofiban group. There was no significant difference in coagulation factor function (R), fibrinogen function (K), fibrinolysis function (EPL), comprehensive coagulation index (Cl), arachidonic acid pathway inhibition rate (AA%) and adenosine diphosphate inhibition rate (ADP%). However, the baseline level of residual platelet function MA (ADP) in eptifibatide group was significantly higher than that in tirofiban group (50.79 vs. 35.29 ​mm, P ​= ​0.0026). There was a statistical difference in the platelet aggregation function MA (65.38 vs. 62.54 ​mm, p ​= ​0.0442), the rate of spontaneous hemorrhagic stroke (4.3% vs. 0%) and the rate of asymptomatic minor bleeding (26.08% vs. 4.1%) in the two groups (P ​< ​0.05).

Conclusion

Both eptifibatide and tirofiban can effectively inhibit platelets, but the effect of etifeptide is better than that of tirofiban in preventing intracranial microhemorrhage and asymptomatic cerebral infarction.

Safety of Glycoprotein IIb-IIIa Inhibitors Used in Stroke-Related Treatment: A Systematic Review and Meta-Analysis

Background:

Endovascular therapy and intravenous thrombolysis with recombinant tissue plasminogen activator are the 2 most recommended treatments for acute ischemic stroke (AIS). Glycoprotein (GP) IIb-IIIa inhibitors are short-acting selective reversible antiplatelet agents that emerged as promising therapeutic agents for AIS about 10 years ago. Given the unclear safety profile and application coverage of GP inhibitors, we conducted this meta-analysis to explore the same.

Methods:

We used GP IIb-IIIa inhibitors, intracranial hemorrhage, and mortality as the key words on Medline, Web of Science, and the Embase databases. Randomized controlled trials, prospective literatures, and retrospective studies in English published between 1990 and 2020 were screened. The outcomes were relative risk (RR) of death and 90-day intracerebral hemorrhage (ICH). We pooled the results in 2 categories and conducted a subgroup analysis stratified by different drugs. The choice of the effects model depended on the value of I².

Results:

In all, 3700 patients from 20 studies were included. No GP IIb-IIIa inhibitors were found to have a remarkable influence on the ICH rate. The RR values of symptomatic ICH for abciximab and eptifibatide were 4.26 (1.89, 9.59) and 0.17 (0.04, 0.69), respectively. Both tirofiban and abciximab could decrease the mortality rate within 90 days. Age > 70 years, National Institutes of Health Stroke Scale > 15, and overall dose > 10 mg are risk factors for ICH events with tirofiban usage. Thrombectomy combined with tirofiban was safe for arterial reocclusion prevention.

Conclusions:

In stroke-related treatment, administration of GP IIb-IIIa inhibitors could be safe, but care should be taken regarding drug species and doses. Abciximab can increase the risk of symptomatic intracranial hemorrhage. Tirofiban and eptifibatide can be considered safe in low doses. Suitable patients should be selected using strict criteria.

Eptifibatide use following emergent carotid stenting in acute anterior circulation ischemic stroke with tandem occlusion

BACKGROUND

Early revascularization of the extracranial internal carotid artery in acute anterior circulation ischemic stroke (ACIS) is feasible and may improve clinical outcome. When a stent is deployed, antithrombotic agents should be administered peri-procedurally to ensure stent patency. Our institution implemented a protocol for the use of eptifibatide as a means of maintaining stent patency in the treatment of ACIS associated with cervical internal carotid artery occlusion.

METHODS

Our internal database was queried for patients who received emergent endovascular therapy (ET) for ACIS with stent placement and eptifibatide administration between July 2016 and 2019.

RESULTS

Twenty nine patients met the study criteria. The etiology was large artery atherosclerosis in 26 cases. Two patients had a dissection (7%), and one had a carotid occlusion related to a recent carotid endarterectomy. Mean NIHSS was 14. Sixteen patients received IVrtPA. Extracranial-intracranial tandem occlusion (TO) was present in 21 of cases. All patients received an eptifibatide bolus followed by an infusion for approximately 24 hours post stent deployment. Head CT was obtained prior to initiation of oral dual antiplatelet therapy with aspirin and clopidogrel. Successful recanalization was achieved in all patients with no evidence of downstream embolization. Symptomatic intracerebral hemorrhage occurred in one patient. Stent occlusion occurred in two patients, only one of which was symptomatic. Favorable clinical outcome with mRS ≤ 2 at 3 months was achieved in seventeen patients.

CONCLUSIONS

The use of eptifibatide post procedure was associated with low risk of symptomatic intracranial hemorrhage, including in patients treated with rtPA.

The "distal-to-proximal" strategy for the treatment of posterior circulation tandem occlusions: a single-centre experience

PURPOSE

Data on posterior circulation tandem occlusions in acute ischemic stroke are scarce: recognition may be challenging and little is known about optimal treatment strategy. We report our endovascular treatment strategy for posterior circulation tandem occlusion.

METHODS

Consecutive patients with posterior circulation tandem occlusions in our centre were enrolled retrospectively. The preferred strategy was "distal-to-proximal" strategy, which means opening the distal occlusion first followed by treatment of the proximal pathology. The imaging characteristics, treatment strategy, clinical outcomes, and complications of patients with posterior circulation tandem occlusions were analyzed.

RESULTS

In total, 21 patients with posterior circulation tandem occlusions were enrolled in the study, which accounted for 23.6% of patients with posterior circulation stroke in our centre. The mean age was 60 years (range 32 to 80), and median pre-procedure NIHSS score was 28 (interquartile range: 13-31). Eighteen patients (85.7%) had vertebrobasilar artery tandem occlusions and 3 (14.3%) had basilar artery to basilar artery tandem occlusions. All distal occlusions were successfully recanalized (modified TICI 2b/3). Two (9.5%) of the proximal lesions were not treated. A total of 57.1% of the patients had stents implanted on the proximal occlusions. The rate of mRS 0-3 at 3 months was 57.1% and the mortality rate was 19.0%.

CONCLUSION

In patients with acute ischaemic stroke caused by posterior circulation tandem occlusions, we favor "distal-to-proximal" strategy based on the positive results in this small series. Nevertheless, a more extensive study is required to explore the optimal treatment strategy further.

Mobile Stroke Units: Bringing Treatment to the Patient

PURPOSE OF REVIEW

Mobile stroke units (MSUs) have revolutionized emergency stroke care by delivering pre-hospital thrombolysis faster than conventional ambulance transport and in-hospital treatment. This review discusses the history of MSUs technological development, current operations and research, cost-effectiveness, and future directions.

RECENT FINDINGS

Multiple prospective and retrospective studies have shown that MSUs deliver acute ischemic stroke treatment with intravenous recombinant tissue plasminogen activator (IV r-tPA) approximately 30 min faster than conventional care. The 90-day modified Rankin Scores for patients who received IV r-tPA on the MSU compared to conventional care were not statistically different in the PHANTOM-S study. Two German studies suggest that the MSU model is cost-effective by reducing disability and improving adjusted quality-life years post-stroke. The ongoing BEST-MSU trial will be the first multicenter, randomized controlled study that will shed light on MSUs' impact on long-term neurologic outcomes and cost-effectiveness. MSUs are effective in reducing treatment times in acute ischemic stroke without increasing adverse events. MSUs could potentially improve treatment times in large vessel occlusion and intracranial hemorrhage. Further studies are needed to assess functional outcomes and cost-effectiveness. Clinical trials are ongoing internationally.

Low-Dose Tirofiban Treatment Improves Neurological Deterioration Outcome After Intravenous Thrombolysis

Background and Purpose—

Early use of antiplatelet drugs within 24 hours after intravenous thrombolysis (IVT) has always been a confusing clinical problem. The purpose of this study was to assess the safety and efficacy of early low-dose tirofiban treatment in patients with early neurological deterioration (END) within the first 24 hours after IVT.

Methods—

This was a retrospective analysis of prospectively collected data of 1764 consecutive patients with acute ischemic stroke treated with IVT between January 2017 and September 2018. Patients with early neurological deterioration within the first 24 hours after IVT were treated with or without tirofiban. The safety outcomes included symptomatic intracranial hemorrhage, any ICH, severe systemic bleeding, and mortality. Efficacy outcomes included excellent (modified Rankin scale scores 0–1) and favorable (modified Rankin scale scores 0–2) 3-month functional outcomes.

Results—

Early neurological deterioration occurred in 278 (15.8%) patients. Of the 187 eligible patients, 121 (64.7%) were treated with tirofiban within the first 24 hours after IVT. Adjusted multivariate analysis showed that early tirofiban use was not associated with symptomatic intracranial hemorrhage (adjusted odds ratio [aOR], 1.05; 95% CI, 0.088–11.02; P =1.000), ICH (aOR, 1.13; 95% CI, 0.45–4.25; P =0.512), and mortality (aOR, 0.77; 95% CI, 0.19–2.27; P =0.875) but was significantly associated with excellent (aOR, 2.24; 95% CI, 1.16–3.94; P =0.027) and favorable (aOR, 2.31; 95% CI, 1.48–3.99; P =0.011) functional outcomes. Subgroup analyses suggested that early tirofiban-use efficacy is time dependent, being more effective in patients receiving tirofiban treatment earlier.

Conclusions—

Low-dose tirofiban use in patients with early neurological deterioration within the first 24 hours after IVT did not increase the risk of symptomatic intracranial hemorrhage, ICH, and mortality, it seems associated with neurological improvement at 3 months. Future randomized clinical trials will be needed to validate these results.

Platelet Glycoprotein IIb/IIIa Receptor Inhibitor Tirofiban in Acute Ischemic Stroke

Tirofiban is a non-peptide selective glycoprotein (GP) IIb/IIIa receptor inhibitor that reversibly inhibits fibrinogen-dependent platelet aggregation and subsequent formation of thrombi, which contribute to the major atherosclerotic complications in the development, progression, and resolution of ischemic stroke. The adjunctive use of tirofiban has been extensively evaluated in progressive stroke, combined intravenous thrombolysis (IVT), and endovascular treatment (EVT) in both preclinical and clinical studies. A body of evidence has been accumulated on the risks and benefits associated with tirofiban in terms of prevention of stroke progression, stent thrombosis, improvement in functional independence, and mortality, especially among high-risk ischemic stroke patients as a further strategy alongside conventional treatment. In general, tirofiban has a favorable tolerability and efficacy profile in the improvement of vascular recanalization and long-term functional outcome, although the optimum dosage, application setting, and precise target patients are not yet well-established. However, its specific inhibition of ongoing platelet aggregation and thrombus formation rather than absolute thrombolysis suggests that tirofiban, one of the most widely used GP IIb/IIIa inhibitors, with high affinity and a short plasma/biologic half-life, may have great potential in the acute treatment of ischemic stroke. Substantial practical progress is likely as our understanding of the mechanism of action and pharmacological actions of tirofiban in atherosclerotic ischemic disease improves. Therefore, we classify and summarize the available findings regarding tirofiban in acute ischemic stroke to stimulate and guide further research and clinical practice.

From Discovery of Snake Venom Disintegrins to A Safer Therapeutic Antithrombotic Agent

Snake venoms affect blood coagulation and platelet function in diverse ways. Some venom components inhibit platelet function, while other components induce platelet aggregation. Among the platelet aggregation inhibitors, disintegrins have been recognized as unique and potentially valuable tools for examining cell–matrix and cell–cell interactions and for the development of antithrombotic and antiangiogenic agents according to their anti-adhesive and anti-migration effect on tumor cells and antiangiogenesis activities. Disintegrins represent a family of low molecular weight, cysteine-rich, Arg-Gly-Asp(RGD)/Lys-Gly-Asp(KGD)-containing polypeptides, which inhibit fibrinogen binding to integrin αIIbβ3 (i.e., platelet glycoprotein IIb/IIIa), as well as ligand binding to integrins αvβ3, and α5β1 expressed on cells (i.e., fibroblasts, tumor cells, and endothelial cells). This review focuses on the current efforts attained from studies using disintegrins as a tool in the field of arterial thrombosis, angiogenesis, inflammation, and tumor metastasis, and briefly describes their potential therapeutic applications and side effects in integrin-related diseases. Additionally, novel R(K)GD-containing disintegrin TMV-7 mutants are being designed as safer antithrombotics without causing thrombocytopenia and bleeding.

Thrombolysis After Protamine Reversal of Heparin for Acute Ischemic Stroke After Cardiac Catheterization: Case Report and Literature Review

BACKGROUND

Patients with an acute ischemic stroke (AIS) following cardiac catheterization (CC) generally do not receive intravenous thrombolysis [intravenous tissue plasminogen activator (IV-tPA)] as it is contraindicated due to the coagulopathy related to the heparin used during the procedure. We report a case of AIS successfully treated with IV thrombolysis following protamine reversal of heparin effect.

CASE REPORT

An 87-year-old man with diabetes mellitus, hypertension, neurofibromatosis, and hyperlipidemia underwent elective transradial CC following an abnormal stress test. He had 2 drug-eluting stents for severe stenosis of mid-circumflex and right coronary arteries and received heparin 13,000 IU during procedure. He developed acute left hemiparesis with initial NIH stroke scale (NIHSS) of 4. Computed tomographic scan of the brain and computed tomographic angiogram of head and neck were unremarkable. Bedside activated clotting time was 181. Protamine 40 mg was administered and 30 minutes later, the activated clotting time level was normalized. IV-tPA was administered at 4 hours 25 minutes from his last known well. Within 15 minutes, his NIHSS was 0. Magnetic resonance imaging of brain showed no acute infarction 24 hours after stroke.

CONCLUSIONS

There are limited reports of protamine reversal of heparin before IV-tPA administration. To our knowledge, there are only 6 AIS cases including ours. Three cases received 0.6 mg/kg of tPA dose. All have favorable outcomes and no intracranial hemorrhage was reported. Protamine reversal of heparin for AIS after CC seems to be safe. Further studies are needed to confirm the therapeutic safety and efficacy of this strategy.

Update in the Early Management and Reperfusion Strategies of Patients with Acute Ischemic Stroke

Acute ischemic stroke (AIS) remains a leading cause of death and long-term disability. The paradigms on prehospital care, reperfusion therapies, and postreperfusion management of patients with AIS continue to evolve. After the publication of pivotal clinical trials, endovascular thrombectomy has become part of the standard of care in selected cases of AIS since 2015. New stroke guidelines have been recently published, and the time window for mechanical thrombectomy has now been extended up to 24 hours. This review aims to provide a focused up-to-date review for the early management of adult patients with AIS and introduce the new upcoming areas of ongoing research.

Phase I and Phase II Therapies for Acute Ischemic Stroke: An Update on Currently Studied Drugs in Clinical Research

Acute ischemic stroke is a devastating cause of death and disability, consequences of which depend on the time from ischemia onset to treatment, the affected brain region, and its size. The main targets of ischemic stroke therapy aim to restore tissue perfusion in the ischemic penumbra in order to decrease the total infarct area by maintaining blood flow. Advances in research of pathological process and pathways during acute ischemia have resulted in improvement of new treatment strategies apart from restoring perfusion. Additionally, limiting the injury severity by manipulating the molecular mechanisms during ischemia has become a promising approach, especially in animal research. The purpose of this article is to review completed and ongoing phases I and II trials for the treatment of acute ischemic stroke, reviewing studies on antithrombotic, thrombolytic, neuroprotective, and antineuroinflammatory drugs that may translate into more effective treatments.

Peptide hormones and lipopeptides: from self-assembly to therapeutic applications

This review describes the properties and activities of lipopeptides and peptide hormones and how the lipidation of peptide hormones could potentially produce therapeutic agents combating some of the most prevalent diseases and conditions. The self‐assembly of these types of molecules is outlined, and how this can impact on bioactivity. Peptide hormones specific to the uptake of food and produced in the gastrointestinal tract are discussed in detail. The advantages of lipidated peptide hormones over natural peptide hormones are summarised, in terms of stability and renal clearance, with potential application as therapeutic agents. © 2017 The Authors Journal of Peptide Science published by European Peptide Society and John Wiley & Sons Ltd.

Low-dose intravenous tissue plasminogen activator for acute ischaemic stroke: an alternative or a new standard?

BACKGROUND

With the recent publication of a large clinical trial on the use of a lower dose of intravenous (IV) tissue plasminogen activator (tPA) for acute ischaemic stroke (AIS), the concept of using a different dose has been debated. We intend to review the literature on using a lower dose of IV tPA and gain a better understanding of the impact of different IV doses on the treatment of patients with AIS.

METHODS

A comprehensive literature search of the related topics in PubMed, EMBASE, Web of Science and MEDLINE was carried out. Key words used include low dose IV tPA, thrombolysis, Alteplace and tPA for AIS. Findings were tabulated according to the size of the cohort studied, outcome, adverse event and level of evidence. The results of all studies using lower doses were analysed for efficacy and adverse events.

RESULTS

From 1992 to 2016, there were 23 trials that included 10 950 patients published on the use of lower doses of IV tPA for AIS. Doses ranged from 0.5, 0.6, 0.75 to 0.85 mg/kg. Most were observational, retrospective and registry studies. One was a prospective open-label randomised controlled trial. 13 trials combined lower doses of IV tPA with a glycoprotein IIb/IIIa inhibitor or thrombectomy. Patients treated with lower doses of IV tPA showed a trend of lower rate of symptomatic intracranial haemorrhage and mortality at 3 months but slightly more disability.

CONCLUSIONS

Lower doses of IV tPA showed less haemorrhagic events but were not more effective compared with the standard dose. The optimal low dose of IV tPA remains unclear. Patients with AIS with a high risk of developing sypmtomatic intracranial haemorrhage might benefit from lower dose IV tPA, such as 0.6 mg/kg.

Safety and Preliminary Efficacy of Early Tirofiban Treatment After Alteplase in Acute Ischemic Stroke Patients

BACKGROUND AND PURPOSE

We investigated whether early initiation of tirofiban, a glycoprotein IIb/IIIa antagonist, is safe, can reduce the risk of reocclusion, and improve outcomes in acute ischemic stroke patients after alteplase.

METHODS

Forty-one patients received alteplase followed by intravenous tirofiban infusion for at least 24 hours. The incidence of symptomatic intracranial hemorrhage, systematic bleedings, and death was recorded. The National Institutes of Health stroke scale score was evaluated at 24 hours and at day 7 (or discharge). Modified Rankin scale was assessed at 3 months. Outcomes for these patients were compared with a propensity score-matched historical cohort with alteplase only.

RESULTS

The incidence of symptomatic intracranial hemorrhage, death, or systematic bleedings (P=1.00) was not increased in the alteplase/tirofiban group. At 24 hours, fewer patients experienced reocclusion in the alteplase/tirofiban group (2.4% versus 22.0%; P=0.025). At day 7 or discharge, the median National Institutes of Health stroke scale score was significantly lower in the alteplase/tirofiban group (1 versus 6; P=0.002). At 3 months, more patients had favorable outcomes of modified Rankin scale 0 to 1 (70.7% versus 46.2%; P=0.026).

CONCLUSIONS

Intravenous tirofiban immediately after alteplase seems to be safe and potentially more effective when compared with alteplase alone for selected stroke patients.

CLINICAL TRIAL REGISTRATION

URL: http://www.chictr.org.cn/. Unique identifier: ChiCTR-TRC-14004630.

Update on the effects of treatment with recombinant tissue-type plasminogen activator (rt-PA) in acute ischemic stroke

INTRODUCTION

Acute ischemic stroke (AIS) represents a major cause of death and disability all over the world. The recommended therapy aims at dissolving the clot to re-establish quickly the blood flow to the brain and reduce neuronal injury. Intravenous administration of recombinant tissue-type plasminogen activator (rt-PA) is clinically used with this goal.

AREAS COVERED

A description of beneficial and detrimental effects of rt-PA treatment is addressed. An overview of new therapies against AIS, such as new thrombolytics, sonolysis and sonothrombolysis, endovascular procedures, and association therapies is provided. Updates on the pathophysiological process leading to intracranial hemorrhage (ICH) is also discussed.

EXPERT OPINION

rt-PA treatment in AIS patients is beneficial to recovery outcomes. To weaken risks and improve benefits, it might be relevant to consider: i) a definitive identification of risk factors for symptomatic ICH; ii). a better organization of the health care system to reduce time-to-treatment and enhance discharge management. The pharmacological improvement of new thrombolytic drugs (such as tenecteplase and desmoteplase) targeting harmful and maximally exploiting beneficial effects might further reduce mortality and disability in AIS.

Effect of waivers of consent on recruitment in acute stroke trials: A systematic review

There is urgent need for clinical trials of novel interventions to reduce the burden of acute ischemic stroke. A key impediment to such trials is slow recruitment. Since obtaining written informed consent in the setting of acute stroke is especially challenging, some experts have endorsed relaxing the requirement for informed consent by permitting verbal consent or waivers to facilitate recruitment. This systematic review of 36 randomized controlled trials of acute interventions for ischemic stroke assesses whether alternatives to written informed consent are associated with increased recruitment rates. After the exclusion of 2 outlier trials that differed from other trials in conduct and interventions studied, no association was observed on univariable analysis (8.9 participants/month in trials requiring written consent vs 6.1 participants/month in trials with alternatives, p = 0.43) or multivariable analysis (when adjusting for the number of centers, number of countries, and exclusions based on modified Rankin Scale scores). Alternatives to written informed consent in acute stroke trials may enable trial designs that would not be feasible otherwise. However, we did not find evidence that, within traditional trial designs, such alternatives are associated with faster recruitment.

Changing Management of Acute Ischaemic Stroke: the New Treatments and Emerging Role of Endovascular Therapy

OPINION STATEMENT

Urgent reperfusion of the ischaemic brain is the aim of stroke treatment, and the last two decades have seen a rapid advancement in the medical and endovascular treatment of acute ischaemic stroke. Intravenous tissue plasminogen activator (tPA) was first introduced as a safe and effective thrombolytic agent followed by the introduction of newer thrombolytic agents as well as anticoagulant and antiplatelet agents, proposed as potentially safer drugs with more favourable interaction profiles. In addition to chemo-thrombolysis, other techniques including transcranial sonothrombolysis and microbubble cavitation have been introduced which are showing promising results, but await large-scale clinical trials. These developments in medical therapies which are undoubtedly of great importance due to their potential widespread and immediate availability are paralleled with gradual but steady improvements in endovascular recanalisation techniques which were initiated by the introduction of the MERCI (Mechanical Embolus Removal in Cerebral Ischemia) and Penumbra systems. The introduction of the Solitaire device was a significant achievement in reliable and safe endovascular recanalisation and was followed by further innovative stent retrievers. Initial trials failed to show a solid benefit in endovascular intervention compared with IV-tPA alone. These counterintuitive results did not last long, however, when a series of very well-designed randomised controlled trials, pioneered by MR-CLEAN, EXTEND-IA and ESCAPE, emerged, confirming the well-believed daily anecdotal evidence. There have now been seven positive trials of endovascular treatment for acute ischaemic stroke. Now that level I evidence regarding the superiority of endovascular recanalisation is abundantly available, the clinical challenge is how to select patients suitable for intervention and to familiarise and educate stroke care providers with this recent development in stroke care. It is important for the interventional services to be provided only in comprehensive stroke centres and endovascular interventions attempted by experienced well-trained operators, at this stage as an adjunct to the established medical treatment of IV-tPA, if there are no contraindications.

Distinct Short-Term Outcomes in Patients With Mild Versus Rapidly Improving Stroke Not Treated With Thrombolytics

BACKGROUND AND PURPOSE

Mild stroke (MS) and rapidly improving stroke (RIS) symptoms are common stroke presentations. Our objective is to describe the short-term outcomes in this population.

METHODS

A retrospective analysis of patients with ischemic stroke in the Get With The Guidelines-Stroke registry who arrived ≤4.5 hours from symptom onset not treated with thrombolytics because of MS and RIS. Outcomes included in-hospital death, home discharge, independent ambulation at discharge, and length of stay; these were analyzed for the categories of MS, RIS, and MS+RIS. Multivariable models evaluated the associations of individual and hospital covariates with outcomes.

RESULTS

Among 42 394 patients with MS and RIS not treated with thrombolytics, 27% were not discharged directly home, 27.2% did not ambulate independently, and 61.1% had length of stay ≥3 days, despite a low in-hospital mortality of 0.8%. Adjusted outcomes were better for MS+RIS compared with MS; RIS also had better independent ambulation and home discharge compared with MS. Among those with a documented National Institutes of Health Stroke Scale, 25% of those with National Institutes of Health Stroke Scale 0 to 5 and half of those with National Institutes of Health Stroke Scale >5 could not be discharged directly to home or ambulate independently. Older individuals, women, blacks, transport by ambulance, delayed arrival, greater severity and greater burden of vascular risk factors, except for dyslipidemia, had worse adjusted outcomes for home discharge and independent ambulation.

CONCLUSIONS

A significant proportion of patients with MS and RIS not treated with thrombolytics have suboptimal discharge outcomes. We found significant differences between MS, RIS, and MS+RIS and identified factors associated with worse outcomes.

[Intravenous thrombolysis in ischemic stroke: Therapeutic perspectives]

New therapeutic strategies are under evaluation to improve the treatment of acute ischemic stroke (AIS). Approaches combining intravenous (IV) thrombolysis with recombinant tissue plasminogen activator (rt-PA) and antithrombotic agents are currently evaluated. The combination of IV rt-PA and aspirin showed a high rate of intracranial hemorrhage whereas the association of rt-PA and eptifibatide seems more promising. The results of recent studies evaluating the administration of eptifibatide or argatroban in conjunction with conventional IV thrombolysis with rt-PA are expected to clarify the safety and efficacy of these treatments. More fibrin-specific plasminogen activators, tenecteplase and desmoteplase, are also investigated. These fibrinolytic agents showed a favorable safety profile but their efficacy in AIS remains uncertain. While phase III studies, DIAS-3 and DIAS-4, evaluating IV desmoteplase up to nine hours after stroke onset did not meet the primary endpoint, the results of studies comparing IV tenecteplase and IV rt-PA are expected.

An Outcome Model for Intravenous rt-PA in Acute Ischemic Stroke

Most early phase trials in stroke and brain trauma have failed in phase 3, including efforts to improve acute ischemic stroke outcomes beyond that achieved by intravenous recombinant tissue plasminogen activator (t-PA) (IVT). With the exception of more recent stent retriever trials, most subsequent phase 3 trials failed. We previously showed that baseline imbalances, non-linear relationships of these factors to outcome, and unrepresentative control populations invalidate traditional statistical analysis in early trials of heterogeneous diseases such as stroke. We developed an alternative approach using a pooled outcome model derived from control arms of randomized clinical trial (RCTs). This model then permits comparing treatment trials to an expected outcome of a pooled population. Here, we hypothesized we could develop such a model for IVT and tested it against outcomes without IVT. We surveyed literature for all trials involving one arm with IVT reporting baseline National Institute Stroke Scale (NIHSS), age, and outcome. A non-linear fit was performed including multi-dimensional statistical intervals (±95 %) permitting visual comparison of outcomes at their own baselines. We compared models derived from non-IVT control arms. Models from 24 IVT RCTs representing 3195 subjects were successfully generated for functional outcome, modified Rankin Scale (mRS) 0-2 (r(2) = 0. 83, p < 0.001), and mortality (r(2) = 0.54; p = 0.001). We confirmed better outcomes compared to no IVT and mixed use IVT models across the range of baseline factors. It was possible to generate an expected outcome model for IVT from existing literature. We confirmed benefit compared to placebo. This model should be useful to compare to new agents without the need for statistical manipulation.

What is the Role for Intra-Arterial Therapy in Acute Stroke Intervention?

Intravenous recombinant tissue plasminogen activator continues to be first-line therapy for patients with acute ischemic stroke presenting within the appropriate time window, but one potential limitation is the low rate of recanalization in the setting of large artery occlusions. Intra-arterial (IA) treatment is effective for emergency revascularization of proximal intracranial arterial occlusions, but proof of benefit has been lacking until recently. Our goal is to outline the history of endovascular therapy and review both IA thrombolysis and mechanical interventions. In addition, we will discuss the impact of important trials such as the Third Interventional Management of Stroke (IMS3) trial, and the more recent trials Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN), Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE), Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial (EXTEND-IA), and Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment (SWIFT PRIME) on acute stroke management and the implications for the practicing neurohospitalist.

Imaging of prehospital stroke therapeutics

Despite significant quality improvement efforts to streamline in-hospital acute stroke care in the conventional model, there remain inherent layers of treatment delays, which could be eliminated with prehospital diagnostics and therapeutics administered in a mobile stroke unit. Early diagnosis using telestroke and neuroimaging while in the ambulance may enable targeted routing to hospitals with specialized care, which will likely improve patient outcomes. Key clinical trials in telestroke, mobile stroke units with prehospital neuroimaging capability, prehospital ultrasound and co-administration of various classes of neuroprotectives, antiplatelets and antithrombin agents with intravenous thrombolysis are discussed in this article.

Combined Approach to Lysis Utilizing Eptifibatide and Recombinant Tissue-Type Plasminogen Activator in Acute Ischemic Stroke-Full Dose Regimen Stroke Trial

BACKGROUND AND PURPOSE

The Combined Approach to Lysis Utilizing Eptifibatide and Recombinant Tissue-Type Plasminogen Activator (r-tPA; CLEAR) in Acute Ischemic Stroke (AIS) and CLEAR-Enhanced Regimen (CLEAR-ER) trials demonstrated safety of reduced dose r-tPA plus the glycoprotein 2b/3a inhibitor, eptifibatide, in AIS compared with r-tPA alone. The objective of the CLEAR-Full Dose Regimen (CLEAR-FDR) trial was to estimate the rate of symptomatic intracerebral hemorrhage (sICH) in AIS patients treated with the combination of full-dose r-tPA plus eptifibatide.

METHODS

CLEAR-FDR was a single-arm, prospective, open-label, multisite study. Patients aged 18 to 85 years treated with 0.9 mg/kg IV r-tPA within 3 hours of symptom onset were enrolled. After obtaining consent, eptifibatide (135 μg/kg bolus and 2-hour infusion at 0.75 μg/kg per minute) was administered. The primary end point was the proportion of patients who experienced sICH within 36 hours. An independent clinical monitor adjudicated if an sICH had occurred and an independent neuroradiologist reviewed all images. The stopping rule was 3 sICHs within the first 19 patients or 4 sICHs within 29 patients.

RESULTS

From October 2013 to December 2014, 27 patients with AIS were enrolled. Median age was 73 years (range, 34-85; interquartile range, 65-80) and median National Institute of Health stroke scale score was 12 (range, 6-26; interquartile range, 9-16). One sICH (3.7%; 95% confidence interval, 0.7%-18%) was observed.

CONCLUSIONS

These results demonstrate comparable safety of full-dose r-tPA plus eptifibatide with historical rates of sICH with r-tPA alone and support proceeding with a phase 3 trial evaluating full-dose r-tPA combined with eptifibatide to improve outcomes after AIS.

Treatment of acute stroke: an update

Stroke is the second leading cause of global mortality after coronary heart disease, and a major cause of neurological disability. About 17 million strokes occur worldwide each year. Patients with stroke often require long-term rehabilitation following the acute phase, with ongoing support from the community and nursing home care. Thus, stroke is a devastating disease and a major economic burden on society. In this overview, we discuss current strategies for specific treatment of stroke in the acute phase, focusing on intravenous thrombolysis and mechanical thrombectomy. We will consider two important issues related to intravenous thrombolysis treatments: (i) how to shorten the delay between stroke onset and treatment and (ii) how to reduce the risk of symptomatic intracerebral haemorrhage. Intravenous thrombolysis has been approved treatment for acute ischaemic stroke in most countries for more than 10 years, with rapid development towards new treatment strategies during that time. Mechanical thrombectomy using a new generation of endovascular tools, stent retrievers, is found to improve functional outcome in combination with pharmacological thrombolysis when indicated. There is an urgent need to increase public awareness of how to recognize a stroke and seek immediate attention from the healthcare system, as well as shorten delays in prehospital and within-hospital settings.

Emergency and critical care management of acute ischaemic stroke

Ischaemic stroke is a devastating condition that is the leading cause of disability in the USA. Over the last 2 decades, the focus of management has shifted from secondary stroke prevention to acute treatment. Coordinated care starts in the field with the emergency medical service providers and continues in the ambulance and the emergency department through to the intensive care unit. After diagnosis and stabilization, a major goal is reperfusion therapy with intravenous fibrinolytics. Neuroimaging research is focused on improving patient selection, expanding treatment windows, and increasing the safety of therapeutic intervention. The role of adjunctive intra-arterial and mechanical thrombectomy remains undefined, and methods to improve reperfusion using sonolysis and new-generation fibrinolytics are currently investigational. Treatment in the intensive care unit targets prevention of secondary brain injury through optimization of blood pressure, cerebral perfusion, glucose, and temperature management, ventilation, and oxygenation. The most feared complications include malignant cerebral edema and symptomatic hemorrhagic transformation. Decompressive craniectomy is life saving, but questions regarding patient selection and timing remain. Hyperosmolar agents are currently used to mitigate cerebral edema, but newer agents to prevent the formation of cerebral edema at the molecular level are being studied. We outline a practical approach to current emergency and intensive care management based on consensus guidelines and the best available evidence.

Targeting integrin and integrin signaling in treating thrombosis

The critical roles of integrins in thrombosis have enabled the successful development and clinical use of the first generation of integrin antagonists as represented by abciximab (Reopro), eptifibatide (Integrilin), and tirofiban (Aggrastat). These integrin αIIbβ3 antagonists are not only potent antithrombotics but also have significant side effects. In particular, their induction of ligand-induced integrin conformational changes is associated with thrombocytopenia. Increased bleeding risk prevents integrin antagonists from being used at higher doses and in patients at risk for bleeding. To address the ligand-induced conformational changes caused by current integrin antagonists, compounds that minimally induce conformational changes in integrin αIIbβ3 have been developed. Recent studies on the mechanisms of integrin signaling suggest that selectively targeting integrin outside-in signaling mechanisms allows for potent inhibition of thrombosis, while maintaining hemostasis in animal models.

Advances in medical revascularisation treatments in acute ischemic stroke

Urgent reperfusion of the ischaemic brain is the aim of stroke treatment and there has been ongoing research to find a drug that can promote vessel recanalisation more completely and with less side effects. In this review article, the major studies which have validated the use and safety of tPA are discussed. The safety and efficacy of other thrombolytic and anticoagulative agents such as tenecteplase, desmoteplase, ancrod, tirofiban, abciximab, eptifibatide, and argatroban are also reviewed. Tenecteplase and desmoteplase are both plasminogen activators with higher fibrin affinity and longer half-life compared to alteplase. They have shown greater reperfusion rates and improved functional outcomes in preliminary studies. Argatroban is a direct thrombin inhibitor used as an adjunct to intravenous tPA and showed higher rates of complete recanalisation in the ARTTS study with further studies which are now ongoing. Adjuvant thrombolysis techniques using transcranial ultrasound are also being investigated and have shown higher rates of complete recanalisation, for example, in the CLOTBUST study. Overall, development in medical therapies for stroke is important due to the ease of administration compared to endovascular treatments, and the new treatments such as tenecteplase, desmoteplase, and adjuvant sonothrombolysis are showing promising results and await further large-scale clinical trials.