Tirofiban for Stroke without Large or Medium-Sized Vessel Occlusion

Translating proof-of-concept for platelet slip into improved antithrombotic therapeutic regimens

Platelets are central to thrombosis. Research at the intersection of biological and physical sciences provides proof-of-concept for shear rate-dependent platelet slip at vascular stenosis and near device surfaces. Platelet slip extends the observed biological "slip-bonds" to the boundary of functional gliding without contact. As a result, there is diminished engagement of the coagulation cascade by platelets at these surfaces. Comprehending platelet slip would more precisely direct antithrombotic regimens for different shear environments, including for percutaneous coronary intervention (PCI). In this brief report we promote translation of the proof-of-concept for platelet slip into improved antithrombotic regimens by: (1) reviewing new supporting basic biological science and clinical research for platelet slip; (2) hypothesizing the principal variables that affect platelet slip; (3) applying the consequent construct model in support of-and in some cases to challenge-relevant contemporary guidelines and their foundations (including for urgent, higher-risk PCI); and (4) suggesting future research pathways (both basic and clinical). Should future research demonstrate, explain and control platelet slip, then a paradigm shift for choosing and recommending antithrombotic regimens based on predicted shear rate should follow. Improved clinical outcomes with decreased complications accompanying this paradigm shift for higher-risk PCI would also result in substantive cost savings.

Platelet glycoprotein IIb/IIIa antagonists in ischemic stroke patients without endovascular therapy: A meta-analysis

Platelet glycoprotein (GP) IIb/IIIa antagonists have been employed in selective patients after endovascular therapy (EVT) for acute ischemic stroke (AIS), yet application in patients without EVT is debated. This meta-analysis of randomized controlled studies on AIS patients without EVT assessed the effectiveness and safety of platelet GP IIb/IIIa antagonists compared with traditional antiplatelet or thrombolysis therapy. Articles were retrieved from databases, including PubMed, Web of Science, EMBASE, and Cochrane. The risk of bias and certainty level of evidence were assessed. Fifteen studies were included. GP IIb/IIIa antagonists increased the proportion of patients with modified Rankin Scale (mRS) 0-1 (odd ratio [OR] 1.37, 95% confidence interval [CI] 1.04-1.81, p = 0.03), mRS 0-2 (OR 1.27, 95% CI 1.12-1.46, p = 0.0004), and Barthel Index (BI) 95-100 (OR 1.25, p = 0.005); decreased the proportion of stroke progression within 5 days (OR 0.66, p = 0.006); and lowered the mean mRS score at 90 days (mean difference [MD] -0.43, p = 0.002) and the National Institute of Health stroke scale score at 7 days (MD -1.64, p < 0.00001) compared with conventional treatment. Proportions of stroke recurrence within 90 days (OR 1.20, p = 0.60), any intracranial hemorrhage (aICH) (OR 1.20, p = 0.12), symptomatic intracranial hemorrhage (sICH) (OR 0.91, p = 0.88), and death (OR 0.87, p = 0.25) had no statistical difference between both groups. This meta-analysis finds that compared with traditional antiplatelet or thrombolysis therapy, GP IIb/IIIa antagonists administered within 24-96 h of ischemic stroke onset significantly improve functional prognosis of patients with AIS not receiving EVT, as indicated by mRS and BI at 90 days, and do not increase the incidence of aICH, sICH, and death.

Evodiamine encapsulated by hyaluronic acid modified zeolitic imidazolate framework-8 for tumor targeted therapy

Evodiamine (EVO), a natural bioactive compound extracted from Evodia rutaecarpa, shows therapeutic ability against malignant melanoma. However, the poor solubility and bioavailability of EVO limit its clinical application. Metal-organic frameworks (MOFs) have shown excellent physical and chemical properties and are widely used as drug delivery systems. Among them, zeolitic imidazolate framework-8 (ZIF-8) is a research popular material because of its unique properties, such as hydrothermal stability, non-toxicity, biocompatibility, and pH sensitivity. In this study, in order to load EVO, a drug carrier that hyaluronic acid (HA) modified zeolitic imidazolate framework-8 (ZIF-8) is synthesized. This drug carrier has shown drug loading with 6.2 ± 0.6%, and the nano drugs (EVO@ZIF-8/HA) have good dispersibility. Owing to the decoration HA of EVO@ZIF-8, the potential of the nano drugs is reversed from the positive charge to the negative charge, which is beneficial to blood circulation in vivo. Furthermore, because the CD44-expressing in tumor cells is excessed, the endocytosis and accumulation of nano drugs in tumor cells are beneficial to improvement. Compared with free EVO, EVO@ZIF-8/HA has shown a significantly improved anti-tumor efficacy in vitro and in vivo. In summary, the drug carrier effectively addresses the challenges that are caused by the strong hydrophobicity and low bioavailability of EVO, thereby targeted tumor therapy of EVO can be achieved.

Efficacy and safety of tirofiban in patients with acute branch atheromatous disease-related stroke (BRANT): a protocol for a randomised controlled trial

INTRODUCTION

Branch atheromatous disease (BAD)-related stroke is increasingly becoming a clinical entity and prone to early neurological deterioration (END) and poor prognosis. There are no effective regimens to reduce the disability caused by BAD-related stroke in acute phase. Recent studies have indicated the efficacy of tirofiban in acute ischaemic stroke; however, its efficacy has not been validated in patients with BAD-related stroke. Thus, we aim to test whether intravenous tirofiban initiated within 48 hours after the onset would improve the functional outcome in patients with acute BAD-related stroke, in comparison with the standard antiplatelet therapy based on the current guideline.

METHODS AND ANALYSIS

BRANT is a multicentre, randomised, open-label, blinded endpoint, parallel-controlled, phase III trial conducted in 21 hospitals in China. Participants aged 18-75 years with acute BAD-related stroke within 48 hours after the stroke onset are randomised in a 1:1 ratio to the tirofiban or control group. The treatment period is 48 hours in both groups. The primary outcome is the excellent functional outcome (modified Rankin Scale Score: 0-1) at 90 days. The secondary outcomes include END, major bleeding, stroke, death, functional status, serious adverse events and change in bleeding-related markers. Assuming the rates of the primary outcome to be 74% in the tirofiban group and 62% in the control group, a total of 516 participants are needed for 0.8 power (two-sided 0.05 alpha).

ETHICS AND DISSEMINATION

BRANT study has been approved by the Ethics Committee of the Peking Union Medical College Hospital (I-23PJ1242). Written informed consent is required for all the patients before enrolment. The results of the study will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT06037889).

Effects of Tirofiban on Neurological Deterioration in Patients With Acute Ischemic Stroke: A Randomized Clinical Trial

Importance

Evidence supports using antiplatelet therapy in patients with acute ischemic stroke. However, neurological deterioration remains common under the currently recommended antiplatelet regimen, leading to poor clinical outcomes.

Objective

To determine whether intravenous tirofiban administered within 24 hours of stroke onset prevents early neurological deterioration in patients with acute noncardioembolic stroke compared with oral aspirin.

Design, Setting, and Participants

This investigator-initiated, multicenter, open-label, randomized clinical trial with blinded end-point assessment was conducted at 10 comprehensive stroke centers in China between September 2020 and March 2023. Eligible patients were aged 18 to 80 years with acute noncardioembolic stroke within 24 hours of onset and had a National Institutes of Health Stroke Scale (NIHSS) score of 4 to 20.

Intervention

Patients were assigned randomly (1:1) to receive intravenous tirofiban or oral aspirin for 72 hours using a central, web-based, computer-generated randomization schedule; all patients then received oral aspirin.

Main Outcome

The primary efficacy outcome was early neurological deterioration (increase in NIHSS score ≥4 points) within 72 hours after randomization. The primary safety outcome was symptomatic intracerebral hemorrhage within 72 hours after randomization.

Results

A total of 425 patients were included in the intravenous tirofiban (n = 213) or oral aspirin (n = 212) groups. Median (IQR) age was 64.0 years (56.0-71.0); 124 patients (29.2%) were female, and 301 (70.8%) were male. Early neurological deterioration occurred in 9 patients (4.2%) in the tirofiban group and 28 patients (13.2%) in the aspirin group (adjusted relative risk, 0.32; 95% CI, 0.16-0.65; P = .002). No patients in the tirofiban group experienced intracerebral hemorrhage. At 90-day follow-up, 3 patients (1.3%) in the tirofiban group and 3 (1.5%) in the aspirin group died (adjusted RR, 1.15; 95% CI, 0.27-8.54; P = .63), and the median (IQR) modified Rankin scale scores were 1.0 (0-1.25) and 1.0 (0-2), respectively (adjusted odds ratio, 1.28; 95% CI, 0.90-1.83; P = .17).

Conclusions and Relevance

In patients with noncardioembolic stroke who were seen within 24 hours of symptom onset, tirofiban decreased the risk of early neurological deterioration but did not increase the risk of symptomatic intracerebral hemorrhage or systematic bleeding.

Trial Registration

ClinicalTrials.gov Identifier: NCT04491695.

Clopidogrel Plus Aspirin vs Aspirin Alone in Patients With Acute Mild to Moderate Stroke: The ATAMIS Randomized Clinical Trial

Importance

Dual antiplatelet therapy has been demonstrated to be superior to single antiplatelet in reducing recurrent stroke among patients with transient ischemic attack or minor stroke, but robust evidence for its effect in patients with mild to moderate ischemic stroke is lacking.

Objective

To evaluate whether dual antiplatelet therapy is superior to single antiplatelet among patients with mild to moderate ischemic stroke.

Design, Setting, and Participants

This was a multicenter, open-label, blinded end point, randomized clinical trial conducted at 66 hospitals in China from December 20, 2016, through August 9, 2022. The date of final follow-up was October 30, 2022. The analysis was reported on March 12, 2023. Of 3065 patients with ischemic stroke, 3000 patients with acute mild to moderate stroke within 48 hours of symptom onset were enrolled, after excluding 65 patients who did not meet eligibility criteria or had no randomization outcome.

Interventions

Within 48 hours after symptom onset, patients were randomly assigned to receive clopidogrel plus aspirin (n = 1541) or aspirin alone (n = 1459) in a 1:1 ratio.

Main Outcomes and Measures

The primary end point was early neurologic deterioration at 7 days, defined as an increase of 2 or more points in National Institutes of Health Stroke Scale (NIHSS) score, but not as a result of cerebral hemorrhage, compared with baseline. The superiority of clopidogrel plus aspirin to aspirin alone was assessed based on a modified intention-to-treat population, which included all randomized participants with at least 1 efficacy evaluation regardless of treatment allocation. Bleeding events were safety end points.

Results

Of the 3000 randomized patients, 1942 (64.6%) were men, the mean (SD) age was 65.9 (10.6) years, median (IQR) NIHSS score at admission was 5 (4-6), and 1830 (61.0%) had a stroke of undetermined cause. A total of 2915 patients were included in the modified intention-to-treat analysis. Early neurologic deterioration occurred in 72 of 1502 (4.8%) in the dual antiplatelet therapy group vs 95 of 1413 (6.7%) in the aspirin alone group (risk difference -1.9%; 95% CI, -3.6 to -0.2; P = .03). Similar bleeding events were found between 2 groups.

Conclusions and Relevance

Among Chinese patients with acute mild to moderate ischemic stroke, clopidogrel plus aspirin was superior to aspirin alone with regard to reducing early neurologic deterioration at 7 days with similar safety profile. These findings indicate that dual antiplatelet therapy may be a superior choice to aspirin alone in treating patients with acute mild to moderate stroke.

Trial Registration

ClinicalTrials.gov Identifier: NCT02869009.

Effects of tirofiban on large vessel occlusion stroke are modified by etiology and renal function

OBJECTIVE

Renal function can modify the outcomes of large vessel occlusion (LVO) stroke across stroke etiologies in disparate degrees. The presence of renal function deficit can also impair the pharmacokinetics of tirofiban. Hence, this study aimed to investigate the roles of renal function in determining efficacy and safety of intravenous tirofiban before endovascular treatment (EVT) for acute ischemic stroke patients with large vessel occlusion (LVO).

METHODS

This study was a post hoc exploratory analysis of the RESCUE-BT trial. The primary outcome was the proportion of patients achieving functional independence (modified Rankin scale 0-2) at 90 days, and the primary safety outcome was the rate of symptomatic intracranial hemorrhage (sICH).

RESULTS

Among 908 individuals with available serum creatinine, decreased estimated glomerular filtration rate (eGFR) status was noted more commonly in patients with cardioembolic stroke (CE), while large artery atherosclerosis (LAA) was predominant in patients with normal renal function. In LAA with normal renal function, tirofiban was associated with higher rates of functional independence at 90 days (41.67% vs 59.80%, p = 0.003). However, for LVO patients with renal dysfunction, tirofiban did not improve functional outcomes for any of the etiologies (LAA, p = 0.876; CE, p = 0.662; others, p = 0.894) and significantly increased the risk of sICH among non-LAA patients (p = 0.020). Mediation analysis showed tirofiban reduced thrombectomy passes (12.27%) and drug/placebo to recanalization time (14.25%) mediated its effects on functional independence.

CONCLUSION

This present study demonstrated the importance of evaluating renal function before administering intravenous tirofiban among patients with LVO who are planned to undergo EVT.

Cost-effectiveness of tirofiban for acute ischemic stroke without large or medium-sized vessel occlusion: A Markov modelling analysis from the Chinese and United States perspectives

BACKGROUND

The RESCUE BT2 trial recently showcased the efficacy of tirofiban in treating acute ischemic stroke (AIS) without large or medium-sized vessel occlusion. To further assess the value of tirofiban from the perspectives of Chinese and US healthcare system, a study was conducted to evaluate its cost-effectiveness.

METHODS

A hybrid model, integrating a short-term decision tree with a long-term Markov model, was developed to assess cost-effectiveness between tirofiban and aspirin for stroke patients without large or medium-sized vessel occlusion. Efficacy data for tirofiban was sourced from the RESCUE BT2 trial, while cost information was derived from published papers. Outcomes measured included respective cost, effectiveness, and incremental cost-effectiveness ratio (ICER). We conducted a one-way sensitivity analysis to assess the robustness of the results. Additionally, we performed probabilistic sensitivity analysis (PSA) through 10,000 Monte Carlo simulations to evaluate the uncertainties associated with the results.

RESULTS

The study revealed that tirofiban treatment in AIS patients without large or medium-sized vessel occlusion led to a considerable reduction of 2141 Chinese Yuan (CNY) in total cost, along with a lifetime gain of 0.14 quality-adjusted life years (QALYs). In the US settings, tirofiban also exhibited a lower cost ($197,055 versus $201,984) and higher effectiveness (4.15 QALYs versus 4.06 QALYs) compared to aspirin. One-way sensitivity analysis revealed that post-stroke care costs and stroke utility had the greatest impact on ICER fluctuation in both Chinese and US settings. However, these variations did not exceed the willingness-to-pay threshold. PSA demonstrated tirofiban's superior acceptability over aspirin in over 95% of potential scenarios.

CONCLUSION

Tirofiban treatment for AIS without large or medium-sized vessel occlusion appeared dominant compared to aspirin in both China and the US.

Perioperative complications of arteriovenous tirofiban administration versus oral dual antiplatelet therapy for stent-assisted embolization treated aneurysmal subarachnoid hemorrhage: A retrospective, controlled cohort analysis

BACKGROUND

Major perioperative complications of stent-assisted embolization treated for aneurysmal subarachnoid hemorrhage patients include the formation of thromboembolic events (TEs) and hemorrhagic events (HEs), for which antiplatelet protocols play a key role.

METHODS

We conducted a single-center retrospective analysis to compare the differences between arteriovenous tirofiban administration with traditional oral dual antiplatelet therapy (DAPT). A total of 417 consecutive patients were enrolled. General clinical characteristics, as well as the perioperative ischemic and hemorrhagic events, were retracted in digital documents. Logistic regression was conducted to identify both risk and protective factors of perioperative TEs and HEs.

RESULTS

Perioperative TEs occurred in 21 patients, with an overall perioperative TEs rate of approximately 5.04%; among these patients, the incidence of perioperative TEs in the tirofiban group was less than that in the DAPT group. Additionally, 66 patients developed perioperative HEs, with an incidence of approximately 15.83%; among these patients, the incidence of perioperative HEs was less than that in the DAPT group. No significant differences were seen between the two groups in terms of the mRS score at the time of discharge.

CONCLUSION

This study indicated that an improved perioperative antiplatelet drug tirofiban was an independent protective factor for perioperative TEs in stent-assisted embolization of ruptured intracranial aneurysms, but it did not impart an elevated risk of perioperative HEs and had no significant effects on the near-term prognosis of the patients.

Clinically important effect sizes for clinical trials using infarct growth reduction as the primary outcome: a systematic review

BACKGROUND

Infarct growth on multimodal imaging is a common lead outcome in phase 2 proof-of-concept and dose-optimization neuroprotective agent stroke trials. However, the effect size in infarct growth reduction that correlates with clinically meaningful differences in clinical global disability outcomes has not been well delineated.

METHODS

A systematic literature search identified all endovascular thrombectomy randomized trials reporting magnitude of treatment effect on both infarct growth reduction and increase in functional independence (modified Rankin Scale (mRS) 0-2). Data aggregation determined the size of infarct growth reductions salient to four types of clinically meaningful effect sizes of increase in functional independence: (1) the minimal clinically important difference (MCID)-outcome specific; (2) the MCID-practice changing; (3) the realistic target difference; and (4) the reasonable comparability effect size.

RESULTS

A systematic search identified four trials enrolling 612 imaged participants. Across the trials, the amount of functional independence (mRS 0-2) increase associated with each 1 mL reduction in infarct growth was mean 2.3±0.6%. An infarct growth reduction of 0.57 mL correlated with the mRS 0-2 increase MCID of 1.3%. Infarct growth reductions of 2.27 mL, 4.35 mL, and 6.53 mL correlated with realistic effect and reasonable comparability effects sizes of mRS 0-2 increases of 5%, 10%, and 15%, respectively.

CONCLUSION

In formal meta-analysis of randomized treatment trials, every 1 mL reduction in infarct growth was associated with a 2.3% increase in functional independence (mRS 0-2) at 3 months. This conversion factor can inform selection of infarct growth effect size targets for phase 2 trials of neuroprotective agents.