Dataset Information

Outcomes Associated With Clopidogrel-Aspirin Use in Minor Stroke or Transient Ischemic Attack: A Pooled Analysis of Clopidogrel in High-Risk Patients With Acute Non-Disabling Cerebrovascular Events (CHANCE) and Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) Trials.

ABSTRACT:

Importance

Dual antiplatelet therapy with clopidogrel and aspirin is effective for secondary prevention after minor ischemic stroke or transient ischemic attack (TIA). Uncertainties remained about the optimal duration of dual antiplatelet therapy for minor stroke or TIA.

Objective

To obtain precise estimates of efficacy and risk of dual antiplatelet therapy after minor ischemic stroke or TIA.

Design, setting, and participants

This analysis pooled individual patient-level data from 2 large-scale randomized clinical trials that evaluated clopidogrel-aspirin as a treatment to prevent stroke after a minor stroke or high-risk TIA. The Clopidogrel in High-Risk Patients With Acute Non-Disabling Cerebrovascular Events (CHANCE) trial enrolled patients at 114 sites in China from October 1, 2009, to July 30, 2012. The Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial enrolled patients at 269 international sites from May 28, 2010, to December 19, 2017. Both were followed up for 90 days. Data analysis occurred from November 2018 to May 2019.

Interventions

In the 2 trials, patients with minor stroke or high-risk TIA were randomized to clopidogrel-aspirin or aspirin alone within 12 hours (POINT) or 24 hours (CHANCE) of symptom onset.

Main outcomes and measures

The primary efficacy outcome was a major ischemic event (ischemic stroke, myocardial infarction, or death from ischemic vascular causes). The primary safety outcome was major hemorrhage.

Results

The study enrolled 5170 patients (CHANCE) and 4881 patients (POINT). Analysis included individual data from 10 051 patients (5016 in the clopidogrel-aspirin treatment group and 5035 in the control group) with a median age of 63.2 (interquartile range, 55.0-72.9) years; 6106 patients (60.8%) were male. Clopidogrel-aspirin treatment reduced the risk of major ischemic events at 90 days compared with aspirin alone (328 of 5016 [6.5%] vs 458 of 5035 [9.1%]; hazard ratio [HR], 0.70 [95% CI, 0.61-0.81]; P < .001), mainly within the first 21 days (263 of 5016 [5.2%] vs 391 of 5035 [7.8%]; HR, 0.66 [95% CI, 0.56-0.77]; P < .001), but not from day 22 to day 90. No evidence of heterogeneity of treatment outcome across trials or prespecified subgroups was observed. Major hemorrhages were more frequent in the clopidogrel-aspirin group, but the difference was nonsignificant.

Conclusions and relevance

In this analysis of the POINT and CHANCE trials, the benefit of dual antiplatelet therapy appeared to be confined to the first 21 days after minor ischemic stroke or high-risk TIA.

SUBMITTER: Pan Y

PROVIDER: S-EPMC6704730 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:Background This study aimed to investigate the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin in Chinese patients by the presence and clinical presentation of intracranial artery stenosis (ICAS) using randomized trial data from the CHANCE-2 (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events-II) trial. Methods and Results A total of 6412 patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles were randomized to either the ticagrelor-aspirin or clopidogrel-aspirin group. Patients without imaging of the intracranial artery were excluded from the nonprespecified subgroup analysis of CHANCE-2. All patients included were classified into the following groups: without ICAS, symptomatic ICAS, or asymptomatic ICAS. The primary efficacy outcome was new strokes within 90 days. There were 5893 patients (median age, 64.8 years; 33.9% women) included, and 172 (4.9%), 171 (10.5%), and 57 (7.7%) cases of new strokes occurred within 90 days in the without ICAS, with symptomatic ICAS, and with asymptomatic ICAS groups, respectively. Ticagrelor-aspirin was associated with reduced risk of new stroke in patients without ICAS (62 [3.5%] versus 110 [6.3%]; hazard ratio [HR], 0.57 [95% CI, 0.41-0.78]) but not in those with symptomatic ICAS (HR, 0.77 [95% CI, 0.56-1.05]) or in those with asymptomatic ICAS (HR, 0.77 [95% CI, 0.43-1.38]) compared with clopidogrel-aspirin (P for interaction=0.14). There were no significant differences in the proportion of severe or moderate bleeding events among different ICAS groups. Conclusions Patients without ICAS received a significantly greater benefit from ticagrelor-aspirin than clopidogrel-aspirin after minor ischemic stroke or transient ischemic attack, and there was no statistically significant difference between treatments in patients with symptomatic ICAS or asymptomatic ICAS. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04078737.

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