Clinical question: Is ticagrelor for secondary prevention indicated for more than one year after myocardial infarction (MI)?
Background: The efficacy and safety of ticagrelor combined with low-dose aspirin more than one year after MI for secondary prevention has not previously been established.
Study design: Randomized, double-blinded, placebo-controlled, clinical trial.
Setting: Multi-center across 31 countries.
Synopsis: Investigators randomized 21,162 patients one to three years after first MI to a 90 mg, twice daily dose; a 60 mg, twice daily dose; or placebo. Patients also received low-dose aspirin (75 mg to 100 mg). Interestingly, a number of patients had been off dual antiplatelet therapy prior to the start of the trial, because most patients were enrolled closer to two years after primary MI. The manufacturer of ticagrelor sponsored the trial.
The study authors’ analysis showed that treating 10,000 patients with the 90 mg dose would prevent 40 cardiac events (cardiovascular death, MI, or stroke), while the 60 mg dose would prevent 42 events; however, the 90 mg dose would cause 41 major bleeding events and the 60 mg dose 31 major bleeding events. Fatal bleeding was less than 1% in all groups, though patients with increased bleeding risk were excluded.
In addition, patients on either dose of ticagrelor had a significantly higher rate of dyspnea, which resulted in increases in drug discontinuation.
Bottom line: Use of ticagrelor with aspirin for secondary prevention greater than one year after myocardial infarction reduced rates of cardiovascular death, MI, and stroke but increased the risk of major bleeding.
Citation: Bonaca MP, Bhatt DL, Cohen M, et al. Long-term use of ticagrelor in patients with prior myocardial infarction. N Engl J Med. 2015;372:1791-1800.
