AstraZeneca's blood-thinner Brilinta failed to prove significantly better than aspirin in preventing recurrent attacks in the 90 days after patients suffer a stroke.
AstraZeneca had hoped the trial results would open up a new market for Brilinta beyond its current use in treating heart attack patients.
Fewer patients taking Brilinta in the trial had a recurrent stroke, suffered a heart attack or died than those on aspirin, but the difference was not statistically significant.
Positive results from the trial would have increased forecasts for Brilinta, which currently stand at an annual $1.87 billion for 2020, according to Thomson Reuters Cortellis.
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