Viewpoint: Mismatch between the European and American guidelines on oral antiplatelet P2Y12 inhibitors after acute coronary syndromes

Recent European Society of Cardiology (ESC) Guidelines declare superiority of prasugrel and ticagrelor over clopidogrel in non-ST segment elevation myocardial infarction (NSTEMI) and STEMI patients with acute coronary syndromes (ACS). The recommendations for NSTEMI and especially STEMI are based on a subgroup analyses yielded from a single trial with either prasugrel (TRITON), or ticagrelor (PLATO). In contrast, the United States (US) Guidelines present a more balanced, conservative, and evidence-based outlook suggesting no proven extra benefit of one P2Y12 antagonist over the other(s). It was the purpose of this study to scrutinise the evidence leading to the current ESC ACS Guidelines on oral antiplatelet agents and compare them with US recommendations. Matching the evidence from TRITON and PLATO primary publications with the data reported in the Food and Drug Administration (FDA) official reviews in light of their impact on current regional ACS Guidelines on antiplatelet P2Y12 inhibitors. The available body of evidence on the efficacy and safety of the new oral P2Y12 inhibitors challenge the ESC Guidelines, and supports the US recommendations. Some of the pivotal data with regard to the newer P2Y12 inhibitors (prasugrel and ticagrelor) on event definition, adjudication, questionable efficacy, and serious safety concerns were ignored by the European Task Force Members, while the other "beneficial" findings were exaggerated to a disproportional extent. We conclude that current ESC Guidelines, with regard to their recommendation of superiority of prasugrel or ticagrelor over clopidogrel, in contrast to the US, are overoptimistic, and not evidence based. Low clinical utilisation of prasugrel and especially ticagrelor worldwide in general, and Europe in particular suggests mismatch of prescription habits with issued ESC recommendations.