Subsequent ischemic stroke and tobacco smoking: A secondary analysis of the POINT trial.

Background: The aim of this study was to determine the effect of smoking status on subsequent stroke risk in patients with minor ischemic stroke or TIA and to determine whether smoking modifies the effect of clopidogrel-based DAPT on subsequent stroke risk. Methods: This was a post-hoc analysis of the Platelet Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial, which had a 90-day follow-up period. We used multivariable Cox regression and subgroup interaction analysis to determine the effect of smoking on the risk of subsequent ischemic stroke and major hemorrhage, respectively. Results: Data from 4877 participants enrolled in the POINT trial were analyzed. Among these, 1004 were current smokers and 3873 were non-smokers at the time of index event. Smoking was associated with a non-significant trend toward an increased risk of subsequent ischemic stroke during follow up (adjusted HR, 1.31 (95% CI, 0.97-1.78), p = 0.076). The effect of clopidogrel on ischemic stroke did not differ between non-smokers (HR, 0.74 (95% CI, 0.56-0.98), p = 0.03) and smokers (HR, 0.63 (95% CI, 0.37-1.05), p = 0.078), p for interaction = 0.572. Similarly, the effect of clopidogrel on major hemorrhage did not differ between non-smokers (hazard ratio, 1.67 (95% CI, 0.40-7.00), p = 0.481) and smokers (HR, 2.59 (95% CI, 1.08-6.21), p = 0.032), p for interaction = 0.613. Conclusions: In this post-hoc analysis of the POINT trial we found that the effect of clopidogrel on reducing subsequent ischemic stroke as well as risk of major hemorrhage did not depend on smoking status, indicating that smokers benefit to a similar degree from DAPT as non-smokers.

Predictors of Recurrent Stroke After Embolic Stroke of Undetermined Source in the RE-SPECT ESUS Trial.

Background We sought to determine recurrent stroke predictors among patients with embolic strokes of undetermined source (ESUS). Methods and Results We applied Cox proportional hazards models to identify clinical features associated with recurrent stroke among participants enrolled in RE-SPECT ESUS (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source) trial, an international clinical trial evaluating dabigatran versus aspirin for patients with ESUS. During a median follow-up of 19 months, 384 of 5390 participants had recurrent stroke (annual rate, 4.5%). Multivariable models revealed that stroke or transient ischemic attack before the index event (hazard ratio [HR], 2.27 [95% CI, 1.83-2.82]), creatinine clearance <50 mL/min (HR, 1.69 [95% CI, 1.23-2.32]), male sex (HR, 1.60 [95% CI, 1.27-2.02]), and CHA2DS2-VASc ≥4 (HR, 1.55 [95% CI, 1.15-2.08] and HR, 1.66 [95% CI, 1.21-2.26] for scores of 4 and ≥5, respectively) versus CHA2DS2-VASc of 2 to 3, were independent predictors for recurrent stroke. Conclusions In RE-SPECT ESUS trial, expected risk factors previously linked to other common stroke causes were associated with stroke recurrence. These data help define high-risk groups for subsequent stroke that may be useful for clinicians and for researchers designing trials among patients with ESUS. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239120.

Ticagrelor Versus Aspirin in Acute Embolic Stroke of Undetermined Source.

BACKGROUND AND PURPOSE: Ticagrelor is an effective antiplatelet therapy among patients with atherosclerotic disease and, therefore, could be more effective than aspirin in preventing recurrent stroke and cardiovascular events among patients with embolic stroke of unknown source (ESUS), which includes patients with ipsilateral stenosis <50% and aortic arch atherosclerosis. METHODS: We randomized 13 199 patients with a noncardioembolic, nonsevere ischemic stroke or high-risk transient ischemic attack to ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2-90) or aspirin (300 mg on day 1 followed by 100 mg daily for days 2-90) within 24 hours of symptom onset. In all patients, investigators informed on the presence of ipsilateral stenosis ≥50%, small deep infarct <15 mm, and on cardiac source of embolism detected after enrollment or rare causes, which allowed to construct an ESUS category in all other patients with documented brain infarction. The primary end point was the time to the occurrence of stroke, myocardial infarction, or death within 90 days. RESULTS: ESUS was identified in 4329 (32.8%) patients. There was no treatment-by-ESUS category interaction (P=0.83). Hazard ratio in ESUS patients was 0.87 (95% confidence interval, 0.68-1.10; P=0.24). However, hazard ratio was 0.51 (95% confidence interval, 0.29-0.90; P=0.02) in ESUS patients with ipsilateral stenosis <50% or aortic arch atherosclerosis (n=961) and 0.98 (95% confidence interval, 0.76-1.27; P=0.89) in the remaining ESUS patients (n=3368; P for heterogeneity =0.04). CONCLUSIONS: In this post hoc, exploratory analysis, we found no treatment-by-ESUS category interaction. ESUS subgroups have heterogeneous response to treatment (Funded by AstraZeneca). CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720.

Risk for Major Bleeding in Patients Receiving Ticagrelor Compared With Aspirin After Transient Ischemic Attack or Acute Ischemic Stroke in the SOCRATES Study (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes).

BACKGROUND: Patients with minor acute ischemic stroke or transient ischemic attack are at high risk for subsequent stroke, and more potent antiplatelet therapy in the acute setting is needed. However, the potential benefit of more intense antiplatelet therapy must be assessed in relation to the risk for major bleeding. The SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes) was the first trial with ticagrelor in patients with acute ischemic stroke or transient ischemic attack in which the efficacy and safety of ticagrelor were compared with those of aspirin. The main safety objective was assessment of PLATO (Platelet Inhibition and Patient Outcomes)-defined major bleeds on treatment, with special focus on intracranial hemorrhage (ICrH). METHODS: An independent adjudication committee blinded to study treatment classified bleeds according to the PLATO, TIMI (Thrombolysis in Myocardial Infarction), and GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) definitions. The definitions of ICrH and major bleeding excluded cerebral microbleeds and asymptomatic hemorrhagic transformations of cerebral infarctions so that the definitions better discriminated important events in the acute stroke population. RESULTS: A total of 13 130 of 13 199 randomized patients received at least 1 dose of study drug and were included in the safety analysis set. PLATO major bleeds occurred in 31 patients (0.5%) on ticagrelor and 38 patients (0.6%) on aspirin (hazard ratio, 0.83; 95% confidence interval, 0.52-1.34). The most common locations of major bleeds were intracranial and gastrointestinal. ICrH was reported in 12 patients (0.2%) on ticagrelor and 18 patients (0.3%) on aspirin. Thirteen of all 30 ICrHs (4 on ticagrelor and 9 on aspirin) were hemorrhagic strokes, and 4 (2 in each group) were symptomatic hemorrhagic transformations of brain infarctions. The ICrHs were spontaneous in 6 and 13, traumatic in 3 and 3, and procedural in 3 and 2 patients on ticagrelor and aspirin, respectively. In total, 9 fatal bleeds occurred on ticagrelor and 4 on aspirin. The composite of ICrH or fatal bleeding included 15 patients on ticagrelor and 18 on aspirin. Independently of bleeding classification, PLATO, TIMI, or GUSTO, the relative difference between treatments for major/severe bleeds was similar. Nonmajor bleeds were more common on ticagrelor. CONCLUSIONS: Antiplatelet therapy with ticagrelor in patients with acute ischemic stroke or transient ischemic attack showed a bleeding profile similar to that of aspirin for major bleeds. There were few ICrHs. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720.

Efficacy and safety of ticagrelor versus aspirin in acute stroke or transient ischaemic attack of atherosclerotic origin: a subgroup analysis of SOCRATES, a randomised, double-blind, controlled trial.

BACKGROUND: Ticagrelor is an effective antiplatelet therapy for patients with coronary atherosclerotic disease and might be more effective than aspirin in preventing recurrent stroke and cardiovascular events in patients with acute cerebral ischaemia of atherosclerotic origin. Our aim was to test for a treatment-by-ipsilateral atherosclerotic stenosis interaction in a subgroup analysis of patients in the Acute Stroke or Transient Ischaemic Attack Treated with Aspirin or Ticagrelor and Patient Outcomes (SOCRATES) trial. METHODS: SOCRATES was a randomised, double-blind, controlled trial of ticagrelor versus aspirin in patients aged 40 years or older with a non-cardioembolic, non-severe acute ischaemic stroke, or high-risk transient ischaemic attack from 674 hospitals in 33 countries. We randomly allocated patients (1:1) to ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2-90, given orally) or aspirin (300 mg on day 1 followed by 100 mg daily for days 2-90, given orally) within 24 h of symptom onset. Investigators classified all patients into atherosclerotic and non-atherosclerotic groups for the prespecified, exploratory analysis reported in this study. The primary endpoint was the time to occurrence of stroke, myocardial infarction, or death within 90 days. Efficacy analysis was by intention to treat. The SOCRATES trial is registered with ClinicalTrials.gov, number NCT01994720. FINDINGS: Between Jan 7, 2014, and Oct 29, 2015, we randomly allocated 13 199 patients (6589 [50%] to ticagrelor and 6610 [50%] to aspirin). Potentially symptomatic ipsilateral atherosclerotic stenosis was reported in 3081 (23%) of 13 199 patients. We found a treatment-by-atherosclerotic stenosis interaction (p=0·017). 103 (6·7%) of 1542 patients with ipsilateral stenosis in the ticagrelor group and 147 (9·6%) of 1539 patients with ipsilateral stenosis in the aspirin group had an occurrence of stroke, myocardial infarction, or death within 90 days (hazard ratio 0·68 [95% CI 0·53-0·88]; p=0·003). In 10 118 patients with no ipsilateral stenosis, 339 (6·7%) of 5047 patients in the ticagrelor group had an occurrence of stroke, myocardial infarction, or death within 90 days compared with 350 (6·9%) of 5071 in the aspirin group (0·97 [0·84-1·13]; p=0·72). There were no significant differences in the proportion of life-threatening bleeding or major or minor bleeding events in patients with ipsilateral stenosis in the ticagrelor group compared with the aspirin group. INTERPRETATION: In this prespecified exploratory analysis, ticagrelor was superior to aspirin at preventing stroke, myocardial infarction, or death at 90 days in patients with acute ischaemic stroke or transient ischaemic attack when associated with ipsilateral atherosclerotic stenosis. An understanding of stroke mechanisms and causes is important to deliver safe and efficacious treatments for early stroke prevention. FUNDING: AstraZeneca.

Ticagrelor in Acute Stroke or Transient Ischemic Attack in Asian Patients: From the SOCRATES Trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes).

BACKGROUND AND PURPOSE: In the SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes), ticagrelor was not superior to aspirin. Because of differences in patient demographics and stroke disease pattern in Asia, outcomes of ticagrelor versus aspirin were assessed among Asian patients in a prespecified exploratory analysis. METHODS: Baseline demographics, treatment effects, and safety of ticagrelor and aspirin were assessed among Asian patients. Differences in outcomes between groups were assessed using Cox proportional hazard model. RESULTS: A total of 3858 (29.2%) SOCRATES participants were recruited in Asia. Among the Asian patients, the primary end point event occurred in 186 (9.6%) of the 1933 patients treated with ticagrelor, versus 224 (11.6%) of the 1925 patients treated with aspirin (hazard ratio, 0.81; 95% confidence interval, 0.67-0.99). The exploratory P value for treatment-by-region interaction was 0.27. The primary end point event rate in the Asian subgroup was numerically higher than that in the non-Asian group (10.6% versus 5.7%; nominal P<0.01). Among the Asian patients, the rate of PLATO (Platelet Inhibition and Patient Outcomes)-defined major bleeding was similar in the ticagrelor group and the aspirin group (0.6% versus 0.8%; hazard ratio, 0.76; 95% confidence interval, 0.36-1.61). CONCLUSIONS: The event rates were numerically higher in the Asian patients. Among the Asian patients with acute stroke or transient ischemic attacks, there was a trend toward a lower hazard ratio in reducing risk of the primary end point of stroke, myocardial infarction, or death in the ticagrelor group. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720.

Ticagrelor versus Aspirin in Acute Stroke or Transient Ischemic Attack.

BACKGROUND: Ticagrelor may be a more effective antiplatelet therapy than aspirin for the prevention of recurrent stroke and cardiovascular events in patients with acute cerebral ischemia. METHODS: We conducted an international double-blind, controlled trial in 674 centers in 33 countries, in which 13,199 patients with a nonsevere ischemic stroke or high-risk transient ischemic attack who had not received intravenous or intraarterial thrombolysis and were not considered to have had a cardioembolic stroke were randomly assigned within 24 hours after symptom onset, in a 1:1 ratio, to receive either ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2 through 90) or aspirin (300 mg on day 1 followed by 100 mg daily for days 2 through 90). The primary end point was the time to the occurrence of stroke, myocardial infarction, or death within 90 days. RESULTS: During the 90 days of treatment, a primary end-point event occurred in 442 of the 6589 patients (6.7%) treated with ticagrelor, versus 497 of the 6610 patients (7.5%) treated with aspirin (hazard ratio, 0.89; 95% confidence interval [CI], 0.78 to 1.01; P=0.07). Ischemic stroke occurred in 385 patients (5.8%) treated with ticagrelor and in 441 patients (6.7%) treated with aspirin (hazard ratio, 0.87; 95% CI, 0.76 to 1.00). Major bleeding occurred in 0.5% of patients treated with ticagrelor and in 0.6% of patients treated with aspirin, intracranial hemorrhage in 0.2% and 0.3%, respectively, and fatal bleeding in 0.1% and 0.1%. CONCLUSIONS: In our trial involving patients with acute ischemic stroke or transient ischemic attack, ticagrelor was not found to be superior to aspirin in reducing the rate of stroke, myocardial infarction, or death at 90 days. (Funded by AstraZeneca; ClinicalTrials.gov number, NCT01994720.).

Acute Stroke or Transient Ischemic Attack Treated with Aspirin or Ticagrelor and Patient Outcomes (SOCRATES) trial: rationale and design.

RATIONALE: The risk of recurrent ischemia is high in the acute period after ischemic stroke and transient ischemic attack. Aspirin is recommended by guidelines for this indication, but more intensive antiplatelet therapy may be justified. AIMS: We aim to evaluate whether ticagrelor, a potent antiplatelet agent that blocks the P2Y12 receptor without requiring metabolic activation, reduces the risk of major vascular events compared with aspirin when randomization occurs within 24 h after symptom onset of a nonsevere ischemic stroke or high-risk transient ischemic attack. DESIGN: Acute Stroke or Transient Ischemic Attack Treated with Aspirin or Ticagrelor and Patient Outcomes (SOCRATES) is a randomized, double-blind, event-driven trial and will include an estimated 13,600 participants randomized in 33 countries worldwide to collect 844 primary events. STUDY OUTCOMES: The primary endpoint is the composite of stroke (ischemic or hemorrhagic), myocardial infarction, and death. Time to the first primary endpoint will be compared in the treatment groups during 90-day follow-up, with major hemorrhage serving as the primary safety endpoint. Participants will be followed for an additional 30 days after the randomized treatment period. DISCUSSION: The SOCRATES trial fulfills an important clinical need by evaluating a potent antiplatelet agent as a superior alternative to current standard of care in patients presenting acutely with ischemic stroke or transient ischemic attack.

Antithrombotic management for transient ischemic attack and ischemic stroke (other than atrial fibrillation).

The new definition and risk stratification for transient ischemic attack (TIA) have clear implications for the urgency of evaluation and treatment. The optimal antithrombotic treatment for TIA is being intensively studied. New guidelines for prevention of non-cardioembolic stroke in patients with stroke or TIA recommend the use of antiplatelet agents rather than oral anticoagulation. New antiplatelet drugs are being used in cardiovascular patients, and their role in cerebrovascular patients is being studied. The impact of genetic CYP2C19 polymorphisms is becoming clarified in cardiovascular patients and it is likely these polymorphisms will affect the management of cerebrovascular patients. The results of trials of clopidogrel plus aspirin in patients with lacunar strokes and acute TIAs are forthcoming. The results of CLOSURE I, a study of a patent foramen ovale device closure trial for cryptogenic stroke or TIA, showed no differences in stroke or TIA at 2 years.

Definition and evaluation of transient ischemic attack: a scientific statement for healthcare professionals from the American Heart Association/American Stroke Association Stroke Council; Council on Cardiovascular Surgery and Anesthesia; Council on Cardiovascular Radiology and Intervention; Council on Cardiovascular Nursing; and the Interdisciplinary Council on Peripheral Vascular Disease. The American Academy of Neurology affirms the value of this statement as an educational tool for neurologists.

This scientific statement is intended for use by physicians and allied health personnel caring for patients with transient ischemic attacks. Formal evidence review included a structured literature search of Medline from 1990 to June 2007 and data synthesis employing evidence tables, meta-analyses, and pooled analysis of individual patient-level data. The review supported endorsement of the following, tissue-based definition of transient ischemic attack (TIA): a transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction. Patients with TIAs are at high risk of early stroke, and their risk may be stratified by clinical scale, vessel imaging, and diffusion magnetic resonance imaging. Diagnostic recommendations include: TIA patients should undergo neuroimaging evaluation within 24 hours of symptom onset, preferably with magnetic resonance imaging, including diffusion sequences; noninvasive imaging of the cervical vessels should be performed and noninvasive imaging of intracranial vessels is reasonable; electrocardiography should occur as soon as possible after TIA and prolonged cardiac monitoring and echocardiography are reasonable in patients in whom the vascular etiology is not yet identified; routine blood tests are reasonable; and it is reasonable to hospitalize patients with TIA if they present within 72 hours and have an ABCD(2) score >or=3, indicating high risk of early recurrence, or the evaluation cannot be rapidly completed on an outpatient basis.

Incomplete inhibition of thromboxane biosynthesis by acetylsalicylic acid: determinants and effect on cardiovascular risk.

BACKGROUND: Incomplete inhibition of platelet thromboxane generation, as measured by elevated urinary 11-dehydro thromboxane B(2) concentrations, has been associated with an increased risk of cardiovascular events. We aimed to determine the external validity of this association in aspirin-treated patients enrolled in the Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management and Avoidance (CHARISMA) trial and to determine whether there are any modifiable factors or interventions that lower urinary 11-dehydro thromboxane B(2) concentrations that could thereby reduce cardiovascular risk. METHODS AND RESULTS: Urinary 11-dehydro thromboxane B(2) concentrations were measured in 3261 aspirin-treated patients at least 1 month after they had been randomly assigned to placebo or clopidogrel. Baseline urinary 11-dehydro thromboxane B(2) concentrations in the highest quartile were associated with an increased risk of stroke, myocardial infarction, or cardiovascular death compared with the lowest quartile (adjusted hazard ratio 1.66, 95% CI 1.06 to 2.61, P=0.03). Increasing age, female sex, history of peripheral artery disease, current smoking, and oral hypoglycemic or angiotensin-converting enzyme inhibitor therapy were independently associated with higher urinary concentrations of 11-dehydro thromboxane B(2), whereas aspirin dose > or =150 mg/d, history of treatment with nonsteroidal antiinflammatory drugs, history of hypercholesterolemia, and statin treatment were associated with lower concentrations. Randomization to clopidogrel (versus placebo) did not reduce the hazard of cardiovascular events in patients in the highest quartile of urinary 11-dehydro thromboxane B(2) levels. CONCLUSIONS: In aspirin-treated patients, urinary concentrations of 11-dehydro thromboxane B(2) are an externally valid and potentially modifiable determinant of stroke, myocardial infarction, or cardiovascular death in patients at risk for atherothrombotic events.

A global view of atherothrombosis: baseline characteristics in the Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management, and Avoidance (CHARISMA) trial.

BACKGROUND: The manifestations of atherothrombosis such as myocardial infarction, ischemic stroke, limb ischemia, or cardiovascular death pose a global health care burden. Additional therapies to decrease ischemic events in patients with established vascular disease or at risk for developing vascular disease are necessary. We sought to characterize the risk factors and treatments of a diverse contemporary population of patients with atherothrombosis. METHODS: The CHARISMA trial has enrolled 15,603 patients from around the world. Patients with established coronary, cerebrovascular, or peripheral arterial disease, or those at high risk of developing atherothrombosis due to multiple risk factors, have been randomized to receive either the adenosine diphosphate receptor antagonist clopidogrel or placebo, in addition to background therapy with low- to moderate-dose aspirin. RESULTS: A high percentage of enrolled patients are being treated with statins and angiotensin-converting enzyme inhibitors. In the CHARISMA population, a total of 75.6% of the population had an abnormal body mass index: 42.2% were overweight and 33.4% were obese, with particularly high rates in the United States, especially of morbid obesity. Correspondingly, the prevalence of diabetes was 42%. CONCLUSION: The CHARISMA trial will further characterize atherothrombosis and provide insight into the role of dual antiplatelet therapy in improving outcomes in patients with multiple risk factors or established vascular disease. Of note, the rates of obesity and diabetes in patients with atherothrombosis throughout the world are particularly alarming.

Evidence with antiplatelet therapy and ADP-receptor antagonists.

Antiplatelet drugs have been shown to prevent a range of atherothrombotic events, including transient ischaemic attack (TIA) and ischaemic stroke. Clopidogrel and ticlopidine are adenosine diphosphate (ADP)-receptor antagonists that inhibit ADP-induced fibrinogen binding to platelets, a necessary step in the platelet aggregation process. The Antithrombotic Trialists' Collaboration recently published a major meta-analysis that assessed the effect of antiplatelet therapy in patients with various manifestations of atherosclerosis. In total, this analysis included 135,000 patients in comparisons of antiplatelet agents versus control and 77,000 patients in comparisons of different antiplatelet regimens. This meta-analysis found that overall, antiplatelet therapy reduces the combined odds of stroke, myocardial infarction (MI) or vascular death by 22%, and that antiplatelet agents reduce the odds of a non-fatal stroke by 25% over a wide range of patients with or without a history of cerebrovascular disease. In the CAPRIE trial of clopidogrel versus acetylsalicylic acid (ASA), there was a 10% odds reduction for stroke, MI or vascular death in favour of clopidogrel (p = 0.03). In a meta-analysis performed by the Cochrane Stroke Group, ADP-receptor antagonist therapy significantly reduced the odds of a serious vascular event (stroke, MI or vascular death) by 9% (2p = 0.01) and of any stroke by 12%. The safety/tolerability profile of clopidogrel was superior to that of ticlopidine, and at least as good as that of ASA. In CURE, a long-term benefit was observed with the use of clopidogrel on top of standard therapy (including ASA in all patients), with a 20% relative risk reduction for the primary endpoint of cardiovascular death, MI or stroke (p < 0.001) in patients with unstable angina and non-Q-wave MI. A consistent benefit was seen across all patient subgroups, including patients with a previous history of stroke. More recently, CREDO has demonstrated the incremental benefit of prolonged use of clopidogrel on top of ASA in patients undergoing elective PCI, with a 27% reduction in the combined risk of death, MI or stroke after 12 months of therapy (p = 0.02) and a 25% reduction in stroke over the same time period. The MATCH trial is currently being conducted to test the hypothesis that long-term administration of clopidogrel on top of ASA is superior to clopidogrel alone for the reduction of major ischaemic events in patients with recent TIA or ischaemic stroke who are at high risk of atherothrombotic recurrence. Further trials of clopidogrel on top of standard therapy (including ASA) are planned in neurology; these include SPS3, in patients with small subcortical strokes, and ATARI, in patients who have recently recovered from a TIA.