Results from Astrazeneca's much-anticipated Pegasus study of its Brilinta treatment found that the drug could extend patients' lives following a heart attack, though it did carry risks of increased bleeding.Studying the effects of the blood-thinning drug on 21,000 patients, Astrazeneca found it reduced the likelihood of a subsequent heart attack when taken in conjunction with a daily dose of aspirin.The treatment "significantly reduced the primary composite endpoint of cardiovascular death, myocardial infarction or stroke compared to placebo", Astra said.However, as expected, bleeding was higher when compared to the placebo."Building on the landmark Plato trial in acute coronary syndrome, the positive Pegasus study adds to the body of evidence for Brilinta and is the first prospective trial to evaluate longer term dual antiplatelet therapy in higher risk patients with a history of a heart attack," said Elisabeth Björk, the vice president and head of cardiovascular and metabolic diseases at Astra's Global Medicines Development division."We have just submitted regulatory filings to the European Medicines Agency and the US Food and Drug Administration and we look forward to working with these agencies towards a potential new indication in major markets," she said.Ahead of the Pegasus results last week, UBS had said that a positive outcome "should finally unlock Brilinta's multibillion-dollar potential".However, the market gave a cool reaction the results, with the stock 0.4% lower at 4,539.5p by 10:30.Nevertheless, in a note on Monday UBS said it still sees upside to the current consensus forecast for Brilinta sales of $1.7bn by 2019, which still imply no or low sales uplift from Pegasus.