Impact of COVID-19 pandemic on STEMI thrombolysis and Emergency Department's performance in a non-PCI capable tertiary hospital

INTRODUCTION

Some guidelines had recommended "thrombolysis first" in ST-elevated myocardial infarction (STEMI) during the Coronavirus Disease 2019 (COVID-19) outbreak. The impact of COVID-19 solely on STEMI thrombolysis is lacking as most studies reported outcomes related to percutaneous coronary intervention (PCI) setting. Thus, this study aimed to assess the impact of the COVID-19 pandemic on STEMI thrombolysis outcomes and the Emergency Department's performance in a non-PCI capable centre.

METHODS

This single-centre retrospective study analysed data on consecutive STEMI patients who received thrombolytic therapy from May 2019 to December 2020 (20 months) in a non-PCI capable tertiary hospital. Total population sampling was used in this study. We compared all patients' characteristics and outcomes ten months before and during the pandemic. Regression models were used to assess the impact of COVID-19 pandemic on door-to-needle time (DNT), mortality, bleeding events, and the number of overnight stays.

RESULTS AND DISCUSSION

We analysed 323 patients with a mean age of 52.9 ± 12.9 years and were predominantly male (n = 280, 88.9%). There was a 12.5% reduction in thrombolysis performed during the pandemic. No significant difference in timing from symptoms onset to thrombolysis and DNT was observed. In-hospital mortality was significantly higher during the pandemic (OR 2.02, 95% CI 1.02-4.00, p = 0.044). Bleeding events post thrombolysis remained stable and there was no significant difference in the number of overnight stays during the pandemic.

CONCLUSION

STEMI thrombolysis cases were reduced during the COVID-19 pandemic, with an inverse increase in mortality despite the preserved Emergency Department performance in timely thrombolysis.

Clinical profile and predictors of 30-day all-cause mortality of ST-elevation myocardial infarction (STEMI) patients receiving fibrinolytic therapy in an Asian population

BACKGROUND

Fibrinolysis remains the primary reperfusion strategy for ST-elevation myocardial infarction (STEMI) in many Asian countries. The outcomes and factors affecting mortality in STEMI fibrinolysis in the Asian population are lacking despite being widely used.

OBJECTIVES

This study aimed to assess the clinical profile of patients and predictors affecting STEMI mortality in an Asian population.

METHODS

This single-center retrospective study analyzed data from STEMI patients who received fibrinolytic therapy from 2016 to 2020 in a tertiary hospital. Logistic regression analysis was performed to identify the significant predictors of the 30-day all-cause mortality, the primary outcome.

RESULTS

A total of 859 patients were included. Their mean age was 53.6 ±12.1 years and they were predominantly male (n=769, 89.4%). The majority of them had anterior involvement STEMI (n = 477, 55.5%) and presented with Killip ≥ II (n = 424, 49.4%). The 30-day all-cause mortality was 12.0% (n =  103). The final model found six predictors for 30-day mortality: age ≥75 (aOR 4.784, p < 0.001), female gender (aOR 2.869, p = 0.001), pre-existing hypertension (aOR 1.623, p = 0.046), anterior myocardial infarction (MI) (aOR 1.947, p < 0.001), Killip class (p < 0.001) and heart rate ≥100 at presentation (aOR 1.823, p =  0.016). Following fibrinolytic therapy, five predictors were found to affect 30-day mortality, i.e. failed fibrinolysis (aOR 2.094, p = 0.041), bleeding events, congestive heart failure (aOR 3.554, p = 0.046), ventricular fibrillation/ tachycardia (aOR 5.920, p < 0.001), and atrial fibrillation/ flutter (aOR 2.968, p = 0.016).

CONCLUSION

Our STEMI patients were younger and more ill at presentation. The risk predictors on 30-day all-cause mortality identified in our Asian population allow the clinicians to better triage and manage STEMI patients.

Using real world evidence to generate cost-effectiveness analysis of fibrinolytic therapy in patients with ST-segment elevation myocardial infarction in Thailand

BACKGROUND

Due to limited access to primary percutaneous coronary intervention for the management of ST-segment elevation myocardial infarction (STEMI) in low-to-middle-income countries (LMICs), fibrinolysis serves as a vital alternative reperfusion therapy. Among fibrinolytic agents, the cost-effectiveness of tenecteplase (TNK) in LMICs as compared to streptokinase (SK) for STEMI management remains unknown.

METHODS

Cost-effectiveness was analyzed using a hybrid model consisting of short-term analysis (30-days decision tree model) and long-term analysis (Markov model). Both health care provider and societal perspectives over a lifetime horizon with 3% discount rate were considered. Input parameters were obtained from Thailand's national health database, a network meta-analysis and literature review. Outcome measure was an incremental cost-effectiveness ratio (ICER) determined by an incremental cost per quality-adjusted life years (QALY) gain. An ICER of less than $5,590 per QALY gain is considered cost-effective. Series of sensitivity analyses were also performed.

FINDINGS

From the societal perspective, TNK increases cost by $827 and increases QALY by 0·173. Thus, the ICER is $4,777 per QALY gained. Similarly, the ICER from health care provider perspective is $4,664 per QALY gained. In the probabilistic sensitivity analysis, using 5,590 USD per QALY as threshold, the probability of TNK being cost-effective was 83% from both perspectives. The most influential parameters were risk ratio of death for treatment with TNK compared to SK and drug cost of TNK.

INTERPRETATION

In a resource-limited country like Thailand, tenecteplase is a cost-effective fibrinolytic drug for treatment of STEMI compared to streptokinase.

FUNDING

None.

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.

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.

Statistical analysis plan for the randomized controlled trial Tenecteplase in Wake-up Ischaemic Stroke Trial (TWIST)

BACKGROUND

Patients with wake-up ischemic stroke are frequently excluded from thrombolytic treatment due to unknown symptom onset time and limited availability of advanced imaging modalities. The Tenecteplase in Wake-up Ischaemic Stroke Trial (TWIST) is a randomized controlled trial of intravenous tenecteplase 0.25 mg/kg and standard care versus standard care alone (no thrombolysis) in patients who wake up with acute ischemic stroke and can be treated within 4.5 h of wakening based on non-contrast CT findings.

OBJECTIVE

To publish the detailed statistical analysis plan for TWIST prior to unblinding.

METHODS

The TWIST statistical analysis plan is consistent with the Consolidating Standard of Reporting Trials (CONSORT) statement and provides clear and open reporting.

DISCUSSION

Publication of the statistical analysis plan serves to reduce potential trial reporting bias and clearly outlines the pre-specified analyses.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03181360 . EudraCT Number 2014-000096-80 . WHO ICRTP registry number ISRCTN10601890 .

Impact of poly-arginine peptides R18D and R18 on alteplase and tenecteplase thrombolysis in vitro, and neuroprotective stability to proteolysis

The poly-arginine peptides R18D and R18 represent novel potential neuroprotective treatments for acute ischaemic stroke. Here we examined whether R18D and R18 had any significant effects on the thrombolytic activity of alteplase (tPA) and tenecteplase (TNK) on clots formed from whole blood in an in vitro thrombolysis plate assay. R18D and R18 were examined at concentrations of 0.25, 0.5, 1, 2, 4, 8 and 16 µM during the 1-h thrombolytic assay. We also included the well-characterised neuroprotective NA-1 peptide as a control. R18D, R18 and NA-1 all reduced tPA or TNK percentage clot lysis by 0-9.35%, 0-3.44% and 0-4.8%, respectively. R18D, R18 and NA-1 had a modest and variable effect on the lag time, increasing the time to the commencement of thrombolysis by 0-9.9 min, 0-5.53 min and 0-7.16 min, respectively. Lastly, R18 and NA-1 appeared to increase the maximal activity of the thrombolysis reaction. In addition, the in vitro anti-excitotoxic neuroprotective efficacy of R18D and R18 was not affected by pre-incubation for 1-2 h or overnight with tPA or TNK, whereas only R18D retained high anti-excitotoxic neuroprotective efficacy when pre-incubated in a synthetic trypsin (TrypLE Express). The present in vitro findings suggest that neither R18D or R18 when co-administered with the thrombolytic inducing agents tPA or TNK are likely to have a significant impact when used clinically during clot thrombolysis and confirm the superior proteolytic stability of the R18D peptide.

The outcomes of reperfusion therapy with streptokinase versus tenecteplase in ST-elevation myocardial infarction (STEMI): a propensity-matched retrospective analysis in an Asian population

Background Fibrinolysis using streptokinase or tenecteplase remains the primary reperfusion strategy for ST-elevation myocardial infarction (STEMI) in many Asian countries, including Malaysia. Comparative outcomes of these two fibrinolytic agents in the Asian population were inconclusive despite being widely used. Aim We aimed to assess and compare the outcomes of streptokinase versus tenecteplase in STEMI reperfusion of an Asian population. Method This single-centre retrospective study analysed data on STEMI patients who received fibrinolytic therapy from 2016 to 2020 in the Emergency Department of the largest tertiary hospital in Malaysia. Total population sampling was used in this study. Based on the propensity score matching, 359 patients receiving streptokinase were matched against 359 patients receiving tenecteplase by incorporating 16 variables that potentially affect mortality. 30-day mortality, stroke and major bleeding were the primary outcome measures. Results There was no significant difference in 30-day mortality between streptokinase (n = 39, 11.2%) and tenecteplase (n = 46, 13.2%) groups (p = 0.418). The rates of ischemic strokes [streptokinase (n = 1, 0.3%) versus tenecteplase (n = 3, 0.9%), p = 0.624], intracranial haemorrhage [streptokinase (n = 3, 0.9%) versus tenecteplase (n = 1, 0.3%), p = 0.624] and major bleeding [streptokinase (n = 4, 1.1%) versus tenecteplase (n = 3, 0.9%), p = 0.624], were comparable for the two groups. The incidences of failed thrombolysis were significantly higher in the tenecteplase arm. Hypotension and allergic reaction were significantly higher in the streptokinase arm. Conclusion Streptokinase and tenecteplase are fibrinolytic agents with similar efficacy and safety in STEMI reperfusion therapy in our Asian population.

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.

Evaluation of the tolerability and effectiveness of Tenecteplase in patients with ST-Segment-Elevation Myocardial Infarction in a Secondary Hospital in Malaysia: A Retrospective Case Series

Background

In Malaysia, knowledge regarding the clinical efficacy of tenecteplase (TNK), a fibrin-specific tissue-plasminogen activator, is limited.

Objectives

To evaluate the effectiveness and tolerability of TNK in patients with ST-segment-elevation myocardial infarction in a secondary referral Malaysian hospital.

Methods

This was a single-center retrospective case series based on the medical records of patients with ST-segment-elevation myocardial infarction admitted to the cardiac care unit between January 2016 and May 2019. Data regarding the mortality status and date of death were collected from the database of the National Registration Department of Malaysia.

Results

Data for 30 patients with ST-segment-elevation myocardial infarction, who received weight-adjusted doses of TNK, were analyzed. The patients’ mean (SD) age was 62 (14) years, and 77% were men. The median time to treatment was 265 minutes (interquartile range = 228–660 minutes), and the clinical success rate of thrombolysis was 79%. The overall all-cause in-hospital mortality rate was 33%. The 1-year survival rates were higher in patients achieving a time to treatment ≤360 minutes (P = 0.03), with a trend toward greater survival in this group at 30 days. Similarly, a trend toward lower in-hospital all-cause mortality was observed in this group (21% vs 50%; P = 0.12). Only 1 patient (3%), who had a HAS-BLED score based on hypertension, abnormal liver/renal function, stroke history, bleeding history or predisposition, labile international normalized ratio, old age, drug/alcohol use of 5, developed major bleeding that required blood transfusion. No cases of ischemic stroke, nonmajor bleeding, in-hospital reinfarction, or TNK-induced allergic reaction were identified.

Conclusions

We hypothesized that the mortality-related outcomes of TNK in patients with ST-segment-elevation myocardial infarction were influenced by TTT, with TTT ≤360 minutes indicating a better prognosis than TTT >360 minutes. TNK-induced bleeding-related complications were minimal in low-risk patients. Further local studies are needed to compare TNK's profile with that of streptokinase, which is a common agent currently used in clinical practice in Malaysian public hospitals. (Curr Ther Res Clin Exp. 2021; 82:XXX–XXX)

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.

Clinical outcomes of patients with mitral prosthetic valve obstructive thrombosis treated with streptokinase or tenecteplase

Agent of choice for thrombolytic therapy (TT) in prosthetic valve thrombosis (PVT) is unknown. 84 mitral obstructive-PVT episodes treated with TT (43: Tenecteplase; 41: Streptokinase) were included in this prospective study. The incidence of primary end-point (CCS: complete clinical success, defined as complete or partial hemodynamic success with no complications or surgery) was 84.5% with recurrent PVT as a sole predictor. Bleeding and embolic manifestations were noted in 8.3% and 4.7% of episodes respectively. Tenecteplase use was associated with lower complication rate and a mitral EOA of <0.74 cm² at presentation predicts the need for extended thrombolysis (accuracy, 78.6%).

Tenecteplase in wake-up ischemic stroke trial: Protocol for a randomized-controlled trial

BACKGROUND

Patients with wake-up ischemic stroke who have evidence of salvageable tissue on advanced imaging can benefit from intravenous thrombolysis. It is not known whether patients who do not fulfil such imaging criteria might benefit from treatment, but studies indicate that treatment based on non-contrast CT criteria may be safe. Tenecteplase has shown promising results in patients with acute ischemic stroke. The aim of the Tenecteplase in Wake-up Ischemic Stroke Trial (TWIST) is to compare the effect of thrombolytic treatment with tenecteplase and standard care versus standard care alone in patients with wake-up ischemic stroke selected by non-contrast CT.

METHODS/DESIGN

TWIST is an international, investigator-initiated, multi-centre, prospective, randomized-controlled, open-label, blinded end-point trial of tenecteplase (n = 300) versus standard care (n = 300) in patients who wake up with an acute ischemic stroke and can be treated within 4.5 h upon awakening. Seventy-seven centres in 10 countries (Denmark, Estonia, Finland, Latvia, Lithuania, New Zealand, Norway, Sweden, Switzerland, and the United Kingdom) participate. The primary outcome is the modified Rankin Scale on the ordinal scale (0-6) at three months.

DISCUSSION

TWIST aims to determine the effect and safety of thrombolytic treatment with tenecteplase in patients with wake-up ischemic stroke selected by non-contrast CT.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03181360. EudraCT Number 2014-000096-80.

Clinical outcomes and safety profile of Tenecteplase in wake-up stroke

BACKGROUND

Tenecteplase has probably pharmacological and clinical advantages in the treatment of acute ischemic stroke. There are lacking data about safety and efficacy of tenecteplase in wake-up stroke (WUPS).

AIMS

To investigate safety and efficacy of tenecteplase compared to alteplase in WUPS patients included in NOR-TEST.

METHODS

WUPS patients in NOR-TEST were included in the study based on DWI-FLAIR mismatch. Included patients randomly assigned (1:1) to receive intravenous tenecteplase 0.4 mg/kg (to a maximum of 40 mg) or alteplase 0.9 mg/kg (to a maximum of 90 mg). Neurological improvement was defined as 1) favorable functional outcome at 90 days modified Rankin Scale (mRS) of 0 or 1 and 2) neurological improvement measured with the National Institutes of Health Stroke Scale (NIHSS) of 4 points within 24 hours as compared to admission NIHSS or NIHSS 0 at 24 hours.

RESULTS

Of 1100 patients from 13 stroke centers included in NOR-TEST, 45 were WUPS patients. Of these, 5 patients were stroke mimics and excluded. Of the remaining 40 patients (3.6%), 24 were treated with alteplase (60%). There was no difference in the number of patients achieving a good clinical outcome (mRS 0-1) in either treatment group. Patients treated with tenecteplase showed a better early neurological improvement (87.5% vs 54.2%, P = 0.027). No ICH was detected on MRI/CT 24-28 hours after thrombolysis.

CONCLUSIONS

In WUPS patients treated in NOR-TEST, there was no difference in clinical outcomes at 90 days and no ICH events or deaths were observed in either alteplase- or tenecteplase-treated patients. Clinical Trial Registration-URL: https://www.clinicaltrials.gov. Unique identifier: NCT01949948.

Tenecteplase Versus Reteplase in Acute Myocardial Infarction: A Network Meta-Analysis of Randomized Clinical Trials

Acute myocardial infarction (AMI) is the leading cause of death throughout the world. One of the standard approaches to treatment of AMI is fibrinolysis. The study was conducted to evaluate the clinical efficacy of tenecteplase versus reteplase through network meta-analysis for AMI. Randomized trials were comprehensively searched in PubMed, Scopus, Cochrane library, and Web of Science using appropriate strategies. Quality assessment was done for the papers. The primary and secondary end-points were mortality, TIMI grade 3 flow at 90 min, death or non-fatal stroke, infarction, total stroke and major bleeding. Odds ratios (OR) were computed (95% confidence intervals). After screening 27325 records, eight articles were included with total patients of 49875 to the meta-analysis. Indirect comparison of tenecteplase vs. reteplase showed no significant differences in the risk of mortality (OR = 0.98, p > 0.05), TIMI grade 3 flow at 90 min (OR = 0.77, p > 0.05), death or non-fatal stroke (OR = 1.04, p > 0.05), infarction (OR = 1.11, p > 0.05), total stroke (OR = 2.71, p > 0.05), and major bleeding (OR = 0.81, p > 0.05) (all p > 0.05). Indirect comparison suggests similar efficacy and safety of tenecteplase and reteplase. Hence, the use of each one of the two medicines depends on price, facility, and accessibility of the medicine.

Tenecteplase versus alteplase after acute ischemic stroke at high age

BACKGROUND

Stroke prevalence is increasing with age. Alteplase is the only agent approved for thrombolytic treatment for patients with ischemic stroke, including patients ≥80 years. In the present study, the aim was to compare efficacy and safety of tenecteplase and alteplase in patients ≥80 years.

METHODS

Data from the Norwegian Tenecteplase Stroke Trial, a randomized controlled trial comparing alteplase and tenecteplase, were assessed.

RESULTS

Of the 273 patients ≥80 years included, mean age was 85.5 years.In the intention-to-treat analyses, 43.1% receiving tenecteplase and 39.9% receiving alteplase reached excellent functional outcome (modified Rankin Scale score 0-1) after 3 months (odds ratio (OR) 1.14, 95% confidence interval (CI) 0.70-1.85, p=0.59). No significant differences among patients in the two treatment groups regarding frequency of symptomatic intracranial hemorrhage during the first 48 h were identified (11 (8.5%) in the tenecteplase group, 10 (7.0%) in the alteplase group, OR 1.23, 95% CI 0.50-3.00, p 0.65). Death within 3 months occurred in 18 patients (14.3%) in the tenecteplase group and in 21 (15.3%) in the alteplase group (p 0.84). After excluding stroke mimics, the proportion of patients with excellent functional outcome was 44.1% in the tenecteplase group and 34.4% in the alteplase group (OR 1.50 CI 0.90-2.52, p 0.12).

CONCLUSION

No differences in the efficacy and safety of tenecteplase versus alteplase in patients ≥80 years were identified.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT01949948).

Tenecteplase versus alteplase in acute ischemic stroke: systematic review and meta-analysis

Tenecteplase is a product of genetic modification of recombinant tissue plasminogen activator with superior pharmacodynamic and pharmacokinetic properties. This meta-analysis was to determine whether intravenous thrombolysis with tenecteplase in patients with acute ischemic stroke has better efficacy and safety outcomes than with intravenous alteplase. PubMed, Cochrane Central Register of Controlled Trials, WHO International clinical trials registry platform (ICTRP), Australian New Zealand Clinical Trials Registry (ANZCTR), EU Clinical Trials Register (EU-CTR) and ClinicalTrials.gov were searched for trials comparing tenecteplase with alteplase in acute ischemic stroke. Functional outcomes (modified Rankin Scale at 90 days), early major neurological improvement, rates of any intracerebral haemorrhage, symptomatic intracerebral haemorrhage and mortality rate at 90 days were the outcomes compared. Four randomized controlled trials involving 1334 patients were included. The Tenecteplase group compared to the alteplase group had significantly better early major neurological improvement (RR = 1.56, 95% CI [1.00, 2.43], p = 0.05). There was no significant difference between tenecteplase and alteplase in excellent functional outcome at 90 days, good functional outcome at 90 days, any intracerebral haemorrhage, symptomatic intracerebral haemorrhage or mortality at 90 days. Our meta-analysis found tenecteplase to be significantly favouring one outcome: early major neurological improvement. Other outcomes did not differ between the tenecteplase and alteplase groups. Trials of cost-effective/benefit analysis comparing tenecteplase versus alteplase and tenecteplase versus endovascular treatment are necessary to reinforce the evidence for the potential cost advantage of tenecteplase.

In vitro examination of the thrombolytic efficacy of tenecteplase and therapeutic ultrasound compared to rt-PA

BACKGROUND

Optimizing thrombolytic therapy is vital for improving stroke outcomes. We aimed to develop standardized thrombolysis conditions to evaluate the efficacy of tenecteplase (TNK) compared to the current gold standard rt-PA (alteplase), with and without additional ultrasound treatment. We also wanted to introduce a new analytical approach to quantify fibrin fiber density in transmission electron microscopy (TEM).

METHODS

In vitro clots that are similar to ex vivo clots concerning their histological condition and their durability were generated from whole blood. For five treatment groups we compared relative clot weight loss (each n = 60) and fibrin fiber density in TEM (each n = 5). The control group (A) was treated only with plasma. Two groups were designated for each rt-PA (B + C) and TNK (D + E). Groups C and E were additionally treated with ultrasound. Dosages were 50 μg/ml for rt-PA and 30 μg/ml for TNK. Results were evaluated by using analyses of variance (ANOVA) and post-hoc t-tests.

RESULTS

Weight loss was increased significantly for all groups compared to the control group. Both TNK groups showed significantly increased weight loss compared to their counterpart rt-PA group (p ≤ 0.001). For TEM only group D showed significantly decreased fibrin fiber density (p < 0.05) compared to both rt-PA groups. Ultrasound did not significantly increase dissolution of clots with either method (best p = 0.16).

CONCLUSIONS

Tenecteplase dissolved clots more effectively than rt-PA with and without ultrasound. A higher sample size could provide more convincing results for TEM.

Enhancement of Expression Level of Modified t-PA (TNKase) in Leishmania tarentolae by Induction System

Background

The expression of bio-therapeutic proteins in mammalian cells, such as CHO, attains high homogeneity related to post-translational modifications. Although CHO remains the most popular cell line for bestselling biotherapeutic proteins on the market, there are still drawbacks such as expensive culture media, long time line, and high drug cost. Recently, researches on a novel Leishmania protozoan system have confirmed that this low-level eukaryote could represent a competitive alternative to the mammalian cell lines.

Methods

The full length of coding sequence of modified tPA TNKase (tenecteplase) was synthesized and cloned into an inducible expression vector of L. tarentolae T7-TR cells.

Results

The expression of the construct was driven by a Tet-inducible promoter. A Leishmania secretory signal sequence was also added to the expression cassette to facilitate the release of the recombinant protein into the medium. The secretory recombinant protein was analyzed and confirmed by SDS-PAGE and Western blot analyses. The expression level of TNKase in this novel system of L. tarentolae was 810 IU/mL after induction, which means that the percentage of expression increases two times compared to previous models in L. tarentolae. The TNKase activity was comparable with Activase.

Conclusion

Our results suggested that expressed TNK (modified tPA) is functionally compatible with Activase regarding their effect on fibrinolysis. Given the post-translational modification similarities between mammalian and L. tarentolae, it is speculated that this system is capable of producing complex proteins such as tPA similar to mammalian system, with easier manipulation and non-expensive method.

Tenecteplase utility in acute ischemic stroke patients: A clinical review of current evidence

INTRODUCTION

Acute ischemic stroke is a leading cause of disability in the United States. Treatment is aimed at reducing impact of cerebral clot burden and life-long disability. Traditional fibrinolytic treatment with recombinant tissue plasminogen activator (tPA) has shown to be effective but at high risk of major bleeding. Multiple studies have evaluated tenecteplase as an alternative to tPA.

OBJECTIVE

This review evaluates literature and utility of tenecteplase for treatment of acute ischemic stroke.

DISCUSSION

Tenecteplase is modified, third generation fibrinolytic with greater specificity for fibrin bound clots. Current data in acute myocardial infarction suggest decreased bleeding events compared to alteplase. Multiple trials have investigated superiority of tenecteplase compared to tPA for treatment of acute ischemic stroke. Current guidelines designate tenecteplase as an alternative treatment for mild acute ischemic stroke patients based on recent literature.

CONCLUSION

Recent emerging literature and limited recommendation guidance from governing medical societies leave many emergency medicine providers to weigh benefit versus risk of fibrinolytic therapy and tenecteplase's place in therapy. This review evaluates the available literature regarding tenecteplase and its utility in the treatment of acute ischemic stroke patients.

Tenecteplase versus alteplase for management of acute ischemic stroke: a pairwise and network meta-analysis of randomized clinical trials

Tenecteplase is a genetically mutated variant of alteplase with superior pharmacodynamic and pharmacokinetic properties. However, its efficacy and safety in acute ischemic strokes are limited. Hence, we conducted a study to evaluate the efficacy and safety of tenecteplase compared with alteplase in acute ischemic stroke. Electronic databases were searched for randomized clinical trials (RCTs) comparing tenecteplase with alteplase in acute ischemic stroke patients eligible for thrombolysis. We evaluated various efficacy and safety outcomes using random-effects models for both pairwise and Bayesian network meta-analyses along with meta-regression analyses. We included 5 RCTs with a total of 1585 patients. Compared with alteplase, tenecteplase treatment was associated with significantly greater complete recanalization (odd ratio [OR] 2.01; 95% confidence interval [CI] 1.04-3.87; p = 0.04) and early neurological improvement (OR 1.43; 95% CI 1.01-2.03; p = 0.05). There were no differences between the two thrombolytics in terms of excellent recovery (modified Rankin Scale [mRS] 0-1; OR 1.17; 95% CI 0.95-1.44; p = 0.13), functional independence (mRS 0-2; OR 1.24; 95% CI 0.78-1.98), poor recovery (mRS 4-6; OR 0.78; 95% CI 0.49-1.25; p = 0.31), complete/partial recanalization (OR 1.51; 95% CI 0.70-3.26; p = 0.30), any intracerebral hemorrhage (OR 0.81; 95% CI 0.56-1.17; p = 0.26), symptomatic intracerebral hemorrhage (OR 0.98; 95% CI 0.52-1.83; p = 0.94), or mortality (OR 0.83; 95% CI 0.54-1.26; p = 0.38). In network meta-analysis, there were better efficacy and imaging-based outcomes with tenecteplase 0.25 mg/kg without increased risk of safety outcomes. Our results demonstrate that in acute ischemic stroke, thrombolysis with tenecteplase is at least as effective and safe as alteplase.

Effect of irrigation on fibrinolytic rtPA therapy in a clot model of intracerebral haemorrhage: a systematic in vitro study

OBJECTIVE

Although fibrinolytic therapy is an upcoming treatment for intracerebral haemorrhage (ICH), standard guidelines are lacking, and some clinical issues persist. Here, we used our recently devised clot model of ICH to systematically analyse effects of irrigation and cerebrospinal fluid (CSF) on fibrinolysis.

METHODS

In vitro clots of human blood (25 ml) were generated and a catheter irrigation system was applied to deliver fluid/treatment. Clots were weighed before and after treatment and compared to rtPA treatment alone. First various drainage periods (15, 30 and 60 min; n = 3 each) and irrigation rates (0, 15, 90 and 180 ml/h; n = 3-5 each) were tested, followed by rtPA administration (1 mg, 15 min incubation) at each irrigation rate. Potential fibrinolytic effect of CSF was examined by incubation with 5 ml healthy vs. haemorrhagic CSF (n = 3 each). To assess a washout effect treatment with saline (0.9%), rtPA (1 mg) and high-rate irrigation (180 ml/h) were compared with measuring plasminogen level before and after. Furthermore clots were treated with a combination of plasminogen (150% serum concentration) and rtPA (1 mg).

RESULTS

Relative clot end weights after 60 min irrigation system treatments were 66.3 ± 3.8% (0 ml/h), 46.3 ± 9.5% (15 ml/h), 46.5 ± 7.1% (90 ml/h) and 53.3 ± 4.1% (180 ml/h). At a lower irrigation rate (15 ml/h), relative end weights were lowest (49.5 ± 4.6%) after 60 min (15 min: 62 ± 4.3%, p = 0.016; 30 min: 62.90 ± 1.88%, p = 0.012). The combination of rtPA and irrigation produced following relative end weights: 0 ml/h, 35 ± 3.2%; 15 ml/h, 32.1 ± 5.7%; 90 ml/h, 36.7 ± 6.3% and 180 ml/h, 41.9 ± 7.5%. No irrigation (0 ml/h) versus rtPA alone showed a significant difference (p < 0.0001) in higher clot weight reduction by rtPA. Similar rtPA+15 ml/h irrigation achieved a significant higher weight reduction compared to 15 ml/h irrigation alone (p = 0.0124). No differences were evident at 90 and 180 ml/h irrigation rates with and without rtPA. Healthy (55.1 ± 5%) or haemorrhagic (65.2 ± 6.2%) CSF showed no fibrinolytic activity. Plasminogen levels in clots declined dramatically (> 80% initially to < 10%) after 1 mg single rtPA dosing and high-rate (180 ml/h) irrigation. The fibrinolytic benefit of adding plasminogen to rtPA was marginal.

CONCLUSIONS

In our in vitro clot model, irrigation combined with rtPA (vs. rtPA alone) conferred no added lytic benefit. Likewise, exposure to haemorrhagic CSF did not increase clot lysis.

Penumbral Imaging-Based Thrombolysis with Tenecteplase Is Feasible up to 24 Hours after Symptom Onset

BACKGROUND AND PURPOSE

Thrombolysis >4.5 hours after ischemic stroke onset is unproven. We assessed the feasibility of tenecteplase (TNK) treatment in patients with evidence of an ischemic penumbra 4.5 to 24 hours after onset.

METHODS

Acute ischemic stroke patients underwent perfusion computed tomography (CT)/magnetic resonance imaging. Patients with cerebral blood volume (CBV) or diffusion weighted imaging Alberta Stroke Program Early CT Scores (ASPECTS) >6 and mismatch score >2 (defined as >2 ASPECTS regions with delay on mean transit time maps and normal CBV) were eligible for treatment with TNK (0.25 mg/kg). Patients with mismatch patterns enrolled in non-endovascular/non-thrombolysis trials and those without mismatch patterns served as comparators.

RESULTS

The median (interquartile range) baseline National Institutes of Health Stroke Scale (NIHSS) in TNK treated patients (n=16) was 12 (range, 8 to 15). In the untreated mismatch (n=18) and nonmismatch (n=23) groups, the baseline NIHSS was 12 (range, 7 to 12) and 16 (range, 8 to 20; P=0.09) respectively. There was one symptomatic hemorrhage each in the TNK group (parenchymal hematoma [PH] 2) and non-mismatch group (PH 2). Penumbral salvage volumes were higher in TNK treated patients (48.3 mL [range, 24.9 to 80.4]) than the non-mismatch (-90.8 mL [range, -197 to -20]; P<0.0001) patients.

CONCLUSIONS

This prospective, non-randomized study supports the feasibility of TNK therapy in patients with evidence of ischemic penumbra 4 to 24 hours after onset.

Tenecteplase versus streptokinase thrombolytic therapy in patients with mitral prosthetic valve thrombosis

Objective

Prosthetic valve thrombosis (PVT) is a dreadful complication of mechanical prosthetic valves. Thrombolytic therapy (TT) for PVT is an alternative to surgery and currently making a leading role. This study compares TT with tenecteplase (TNK) and streptokinase (SK) head to head in patients with mitral PVT.

Methods

In this single center, observational study, patients with mitral PVT diagnosed by clinical data, transthoracic echocardiography, transesophageal echocardiography, and fluoroscopy were included. After excluding patients with contraindications for thrombolysis, they were randomly assigned to receive either SK or TNK regimen. Patients were monitored for success or failure of TT and for any complications.

Results

Among 52 episodes (47 patients with 5 recurrences) of mechanical mitral PVT, 40 patients were thrombolyzed with SK and 12 patients were thrombolyzed with TNK. Baseline characteristics including demographic profile, clinical and echocardiographic features, and valve types were not statistically significant between the groups. Complete success rate was 77.5% in SK group and 75% in TNK group (p = 0.88). Partial success rate, failure rate, and major complications were not statistically significant between the two groups. Within 12 h of therapy, TNK showed complete success in 33.3% of patients compared to 15% in SK group (p-value <0.02). Minor bleeding was more common in TNK group.

Conclusion

Slow infusion of TNK is equally efficacious but more effective than SK in the management of mitral mechanical PVT. 75% to 77.5% of PVT patients completely recovered from TT and it should be the first line therapy where the immediate surgical options were remote.