Mechanism of action and clinical development of ticagrelor, a novel platelet ADP P2Y₁₂receptor antagonist

Inhibition of the platelet ADP P2Y(12) receptor has shown to be associated with a marked risk reduction of atherothrombotic events in high-risk settings, including patients with acute coronary syndromes and those undergoing percutaneous coronary interventions. Clinical and laboratory experiences have led to a better comprehension of the drawbacks of currently available P2Y(12) receptor antagonists, stimulating the development of novel agents. Ticagrelor (AZD6140) is the first drug of a new chemical class called cyclopentyltriazolopyrimidine, which is administered orally and has a reversible P2Y(12) receptor inhibitory effect. Preclinical and early-phase clinical studies have shown ticagrelor to be characterized by a rapid, greater and consistent antiplatelet effect with a favorable safety profile. Recent findings from large-scale Phase III trials showed ticagrelor to be more effective in preventing ischemic events in acute coronary syndrome patients without an increased risk of protocol-defined major bleeding, but with an increase in the rate of nonprocedure-related bleeding, compared with currently recommended treatment regimens. This article provides an overview of the pharmacologic properties and clinical development of ticagrelor.