Compared with aspirin , thienopyridines significantly reduced gastrointestinal adverse effects .
However , thienopyridines increased the odds of skin rash and diarrhoea , ticlopidine more than clopidogrel .
Allocation to ticlopidine , but not clopidogrel , significantly increased the odds of neutropenia .
The thienopyridine derivatives are at least as effective as aspirin in preventing serious vascular events in patients at high risk , and possibly somewhat more so .
However , the size of any additional benefit is uncertain and could be negligible .
Clopidogrel has a more favourable adverse effects profile than ticlopidine and so is the thienopyridine of choice .
BACKGROUND Aspirin is the most widely studied and prescribed antiplatelet agent for preventing serious vascular events , reducing the odds of such events among high vascular risk patients by about a quarter .
Thienopyridine derivatives inhibit platelet activation by a different mechanism and so may be more effective .
OBJECTIVES To determine the effectiveness and safety of thienopyridine derivatives ( ticlopidine and clopidogrel ) versus aspirin for preventing serious vascular events ( stroke , myocardial infa rct ion ( MI ) or vascular death ) in patients at high risk , and specifically in patients with a previous TIA or ischaemic stroke .
Clopidogrel and aspirin versus aspirin alone for the prevention of atherothrombotic events.
BACKGROUND Dual antiplatelet therapy with clopidogrel plus low-dose aspirin has not been studied in a broad population of patients at high risk for atherothrombotic events . METHODS We r and omly assigned 15,603 patients with either clinical ly evident cardiovascular disease or multiple risk factors to receive clopidogrel ( 75 mg per day ) plus low-dose aspirin ( 75 to 162 mg per day ) or placebo plus low-dose aspirin and followed them for a median of 28 months . The primary efficacy end point was a composite of myocardial infa rct ion , stroke , or death from cardiovascular causes . RESULTS The rate of the primary efficacy end point was 6.8 percent with clopidogrel plus aspirin and 7.3 percent with placebo plus aspirin ( relative risk , 0.93 ; 95 percent confidence interval , 0.83 to 1.05 ; P=0.22 ) . The respective rate of the principal secondary efficacy end point , which included hospitalizations for ischemic events , was 16.7 percent and 17.9 percent ( relative risk , 0.92 ; 95 percent confidence interval , 0.86 to 0.995 ; P=0.04 ) , and the rate of severe bleeding was 1.7 percent and 1.3 percent ( relative risk , 1.25 ; 95 percent confidence interval , 0.97 to 1.61 percent ; P=0.09 ) . The rate of the primary end point among patients with multiple risk factors was 6.6 percent with clopidogrel and 5.5 percent with placebo ( relative risk , 1.2 ; 95 percent confidence interval , 0.91 to 1.59 ; P=0.20 ) and the rate of death from cardiovascular causes also was higher with clopidogrel ( 3.9 percent vs. 2.2 percent , P=0.01 ) . In the subgroup with clinical ly evident atherothrombosis , the rate was 6.9 percent with clopidogrel and 7.9 percent with placebo ( relative risk , 0.88 ; 95 percent confidence interval , 0.77 to 0.998 ; P=0.046 ) . CONCLUSIONS In this trial , there was a suggestion of benefit with clopidogrel treatment in patients with symptomatic atherothrombosis and a suggestion of harm in patients with multiple risk factors . Overall , clopidogrel plus aspirin was not significantly more effective than aspirin alone in reducing the rate of myocardial infa rct ion , stroke , or death from cardiovascular causes . ( Clinical Trials.gov number , NCT00050817 . )
Compared with aspirin , thienopyridines significantly reduced gastrointestinal adverse effects .
However , thienopyridines increased the odds of skin rash and diarrhoea , ticlopidine more than clopidogrel .
Allocation to ticlopidine , but not clopidogrel , significantly increased the odds of neutropenia .
The thienopyridine derivatives are at least as effective as aspirin in preventing serious vascular events in patients at high risk , and possibly somewhat more so .
However , the size of any additional benefit is uncertain and could be negligible .
Clopidogrel has a more favourable adverse effects profile than ticlopidine and so is the thienopyridine of choice .
BACKGROUND Aspirin is the most widely studied and prescribed antiplatelet agent for preventing serious vascular events , reducing the odds of such events among high vascular risk patients by about a quarter .
Thienopyridine derivatives inhibit platelet activation by a different mechanism and so may be more effective .
OBJECTIVES To determine the effectiveness and safety of thienopyridine derivatives ( ticlopidine and clopidogrel ) versus aspirin for preventing serious vascular events ( stroke , myocardial infa rct ion ( MI ) or vascular death ) in patients at high risk , and specifically in patients with a previous TIA or ischaemic stroke .