The U.S. Department of Justice (DoJ) closed its investigation into the pivotal PLATO trial and will take no further action, according the drug maker AstraZeneca.

In 2013, the civil division of the DoJ requested that AstraZeneca provide access to documents and information about PLATO (PLatelet Inhibition And paTient Outcomes). PLATO showed that ticagrelor (Brilinta) significantly reduced the rate of death from vascular causes, MI or stroke without an increase in the rate of overall major bleeding compared with clopidogrel (Plavix, Bristol-Myers Squibb) in patients with acute coronary syndrome.

Ticagrelor is an oral, reversible, direct-acting inhibitor of the adenosine diphosphate receptor P2Y12 that received FDA approval in 2011 based on the results of PLATO. The FDA postponed its decision several times before approving the antiplatelet treatment for patients with acute coronary syndrome.

AstraZeneca announced that it is proceeding with several other trials, including SOCRATES, which will evaluate ticagrelor in patients with acute ischemic stroke or transient ischemic attack; EUCLID, for patients with peripheral artery disease; and PEGASUS, as secondary prevention in patients with a previous MI.