Because about 90% of patients had been pretreated with clopidogrel, the study primarily compared the effect of staying on clopidogrel with switching to ticagrelor, the investigators noted. “Our trial was an investigator- initiated trial with limited funding that did not allow a double-dummy design,” they added. “We attempted to minimize the risk of bias associated with the open-label nature of the study by performing blinded outcome adjudication.”
In terms of secondary endpoints, 23 patients (1.2%) on ticagrelor developed major bleeding according to PLATO criteria and Bleeding Academic Research Consortium (BARC) criteria, as did 26 patients (1.4%) on clopidogrel at 30-day follow-up (absolute difference, −0.18%; 95% CI, −0.89% to 0.54; P = .001 for noninferiority). Ticagrelor and clopidogrel also resembled each other in terms of fatal bleeds (0.16% versus 0.11%, respectively; P = .67) and intracranial bleeds (0.42% versus 0.37%; P = .82).
However, minimal PLATO bleeding was significantly more common with ticagrelor (3.2%) than with clopidogrel (2%; P = .02), the researchers reported. Clinically significant TIMI bleeding requiring medical attention occurred in 2% of the ticagrelor group and 1.2% of the clopidogrel group (P = .06), and ticagrelor was no more effective than clopidogrel in terms of preventing death from vascular causes, myocardial infarction, or stroke, with a composite rate of 4% in each arm and a statistically insignificant hazard ratio of (0.91; 95% CI, 0.67 to 1.25; P = .57).
Additionally, while similar proportions of patients stopped treatment because of adverse events, dyspnea was more common with ticagrelor (13.9%) than clopidogrel (7.6%). “Based on our findings, patients with STEMI younger than 75 years who initially received clopidogrel can be safely switched to ticagrelor in the first 24 hours after fibrinolysis,” the researchers wrote. “Whether this strategy will result in fewer cardiovascular events in the long term remains to be determined.”
AstraZeneca makes ticagrelor and funded the trial. Dr. Berwanger disclosed grants and personal fees from AstraZeneca and several other pharmaceutical companies.
Source: JAMA Cardiol. doi:10.1001/jamacardio.2018.0612
© Frontline Medical Communications 2018-2021. Reprinted with permission, all rights reserved.
