Canadian American ticlopidine study (cats) in thromboembolic stroke.

Approximately 1000 patients who have suffered a well-documented thromboembolic stroke within two weeks to four months of study entry will be enrolled in this double-blind, randomized, placebo controlled, parallel group trial. Five Canadian and five United States study centers will participate. The enrollment period will be two and one half years, and follow-up will run for an additional six months to a common termination point at three years. Ticlopidine hydrochloride, administered as two 125 mg tablets b.i.d. (500 mg/day total dose) will be compared with placebo for efficacy in the prevention of recurrent stroke, myocardial infarction, cardiovascular death, and overall mortality. Inclusion and exclusion criteria will be the minimum necessary to provide safety and scientific validity. After a screening visit, qualifying patients will be randomly assigned to ticlopidine or placebo. Follow-up laboratory studies for monitoring complete blood and platelet counts will be made at weeks 2, 4, 6, 8, 10 and 12, and then months 4, 5, 6, 8 and then every 4 months thereafter. Follow-up clinic visits will be made at 1 month, 4 months, and then every four months thereafter for clinical evaluation and for dispensing test medication. Study outcome events will be appropriately documented on case report forms. The statistical analysis will evaluate the initial comparability of the two treatment groups, and the principal outcomes of the two groups will be compared by using the Mantel-Haenszel life table analysis.