Safety Evaluation of Clopidogrel Sulfate in Patients With Peripheral Arterial Disease

Primary objective: * To evaluate whether 12 weeks of clopidogrel is superior to ticlopidine in terms of lower risk of the safety events of interests in patients with peripheral arterial disease (PAD) Secondary objectives: * To compare the risk of bleeding adverse events, serious adverse events and overall safety of clopidogrel with ticlopidine * To compare the risk of vascular events of clopidogrel with ticlopidine * To document the long-term safety of clopidogrel for a total of 52 weeks * To document the vascular events of clopidogrel for a total of 52 weeks