A sub-analysis of the PEGASUS-TIMI 54 study, assessing the effect of Ticagrelor ( Brilinta, Brilique ) in reducing atherothrombotic events in post-myocardial infarction patients, based on the time from withdrawal of their previous P2Y12 inhibitor antiplatelet therapy.
Current European guidelines recommend that dual antiplatelet therapy is stopped 12 months after a myocardial infarction.
The PEGASUS-TIMI 54 study enrolled patients who had suffered a myocardial infarction one to three years previously.
The data demonstrated that withdrawal from P2Y12 inhibitor antiplatelet therapy is associated with heightened risk of ischaemic events, including cardiovascular death, myocardial infarction or stroke.
Patients enrolled into the placebo arm of the PEGASUS-TIMI 54 study who had recently discontinued previous P2Y12 inhibitor antiplatelet therapy ( within 30 days ) were at heightened risk of developing a subsequent ischaemic event, compared to those who had stopped therapy over 30 days previously, regardless of the time since their original heart attack. This may be due to differences in baseline characteristics ( although adjusted for in this analysis ) as well as exposing continued risk by the withdrawal of therapy.
Those patients randomised into the Ticagrelor arms of the study within 30 days of withdrawal of therapy experienced a 27% reduction in the risk of developing a subsequent event. The benefit of treatment with Ticagrelor had the greatest effect in this group, with the effect on risk decreasing as the length of time from last dose increased [ less than or equal to 30 days HR=0.73; more than 30 days to 360 days HR=0.86; more than 360 days HR=1.01 ].
These findings suggest greater benefit in continuing P2Y12 inhibition beyond 12 months therapy without interruption than in re-initiating such therapy in patients who have remained stable for more than 2 years after myocardial infarction and more than 1 year off of a P2Y12 inhibitor.
The PEGASUS-TIMI 54 study investigated the efficacy and safety of Ticagrelor at both 60 mg and 90 mg twice daily, plus low dose Acetylsalicylic acid ( Aspirin ), compared to placebo plus low dose Acetylsalicylic acid, for the long-term prevention of atherothrombotic events in patients who had suffered a heart attack one to three years prior to study enrolment.
The full results of the PEGASUS-TIMI 54 study were published in the New England Journal of Medicine ( NEJM ) in March 2015. ( Xagena )
Source: European Society of Cardiology - ESC Congress, 2015