Pharmacokinetics and pharmacodynamics of ticagrelor in the treatment of cardiac ischemia

Introduction: After acute coronary syndromes (ACS), the so-called dual antiplatelet therapy (DAPT), which usually consists of low-dose of aspirin in combination with a thienopyridine (clopidogrel, prasugrel) or with a cyclopentyltriazolopyrimidine (ticagrelor), reduces the risk of ischemic events. Ticagrelor, un particular, is an effective drug as it isn' a prodrug, doesn't require metabolic activation and demonstrates a rapid onset and faster offset of action. Areas covered: This article evaluates the pharmacokinetics, efficacy, safety and tolerability of ticagrelor during DAPT after ACS and its potential use beyond the canonical twelve months after PCI. The review discusses studies comparing: ticagrelor and clopidogrel (DISPERSE, DISPERSE-2, PLATO, RESPOND Trial, ONSET/OFFSET Trials), ticagrelor and placebo (PEGASUS TIMI 54 Trial). Expert opinion: For ACS patients, the PLATO trial showed that ticagrelor was superior to clopidogrel in the reduction of cardiovascular death, myocardial infarction and stroke. PEGASUS TIMI 54 showed that patients in whom ischemic events and cardiovascular death outweigh the risk of life-threatening bleeding, may benefit from prolonged ticagrelor-based dual antiplatelet therapy, over 12 months. This strategy has been recently approved by the ACC/AHA guidelines. Further studies are needed to evaluate and eventually validate the role of the prolonged DAPT in patients treated with new generation stents.