July 26, 2021
Keio University School of Medicine
A research group led by Collaborative Researcher Satoshi Shoji and Senior Lecturer Shun Kohsaka of the Division of Cardiology, Department of Internal Medicine, Keio University School of Medicine, has announced the results of a network meta-analysis on the administration of antiplatelet agents, which are essential after an acute myocardial infarction. They have revealed that the optimal strategy is not to continue administering the same drug at the same dose, but to gradually reduce the dosage (a de-escalation strategy).
After an acute myocardial infarction, dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor for approximately one year is recommended to prevent thrombotic reocclusion. In addition to clopidogrel (Plavix®), the earliest approved P2Y12 inhibitor, more potent agents like ticagrelor (Brilinta®) and prasugrel (Effient®) have been newly approved, making a total of three such drugs available today. Of these, the more potent ticagrelor and prasugrel are recommended worldwide, but many studies have also reported that their long-term administration is associated with an increased risk of bleeding.
In this context, reports began to emerge on the effectiveness of a de-escalation strategy, which involves administering a newly approved P2Y12 inhibitor (ticagrelor or prasugrel) for one month after an acute myocardial infarction and then switching to clopidogrel or low-dose prasugrel (aspirin is continued for one year). However, as individual studies were small and had not reached a firm conclusion, our research group conducted an integrated analysis of the efficacy and safety of five dual antiplatelet therapy strategies, including the de-escalation method, using a network meta-analysis.
The results showed that the de-escalation strategy—switching to a more modest dual antiplatelet therapy one month after an acute myocardial infarction rather than continuing it indefinitely—is the most beneficial in terms of both efficacy and safety. This finding is considered particularly important for the Japanese population, which has a high risk of bleeding.
While the utility of dynamically changing the type and dosage of medication has recently become evident in various fields, it is considered extremely rare to obtain results like those of this study, which embody the 'Less is More' principle—that 'dose reduction' is ultimately beneficial for the patient.
These findings were published in the online edition of the international academic journal "Journal of the American College of Cardiology" on July 15, 2021 (Eastern Time).
Please see below for the full press release.