In a randomized double-blind trial, the Study Group compared the effic
acy of E5510, a novel antiplatelet agent, and aspirin in preventing th
e recurrence of transient ischemic attacks (TLA). In total, 227 patien
ts who suffered from TIA in the twelve weeks prior to the study were e
nrolled. They were randomly allocated to three treatment groups, ie, 7
1 patients in the E5510 4 mg group, 77 patients in the E5510 2 mg grou
p, and 79 patients in the aspirin 324 mg group, and were treated for t
welve to twenty-four weeks. The incidence of recurrent TLA or stroke w
as 21.5% in the aspirin group and was significantly lower in the E5510
groups, being 8.5% in the 4 mg group (P < 0.05) and 11.7% in the 2 mg
group (P < 0.05). Adverse events were observed in 5 cases in the 4 mg
group, in 8 cases in the 2 mg group, and in 10 cases in the aspirin g
roup, but none of them were serious. Since safety was judged to be com
parable among the three groups, E5510 appears to be an antiplatelet ag
ent for the treatment of TIA with a clinical benefit over aspirin.