Study CHAMPIONs cangrelor antiplatelet
medwireNews: The fast-acting antiplatelet agent cangrelor significantly reduces the risk for ischemic events, including stent thrombosis, in patients during percutaneous coronary intervention (PCI), without significantly increasing severe bleeding, researchers report.
In their trial of 10,942 patients undergoing PCI and randomly assigned to receive cangrelor or clopidogrel, the researchers found that the odds for an ischemic event within 48 hours of the procedure was a significant 22% lower for those taking cangrelor, with the benefit consistent across all major subgroups.
This yielded a number needed to treat with cangrelor of 84 to prevent one primary endpoint event.
The reduction in ischemic events was largely driven by fewer periprocedural myocardial infarctions with cangrelor than with clopidogrel, note Deepak Bhatt (Veterans Affairs Boston Healthcare System, Massachusetts, USA) and fellow CHAMPION PHOENIX investigators.
The Cangrelor versus Standard Therapy to Achieve Optimal Management of Platelet Inhibition (CHAMPION) PHOENIX trial participants were randomly assigned to receive a bolus and infusion of cangrelor (30 µg/kg then 4 µg/kg per minute) for 2 hours or the duration of the procedure or a loading dose of clopidogrel 600 or 300 mg.
The rate of the composite primary efficacy endpoint of death from any cause, myocardial infarction, ischemia-driven revascularization, or stent thrombosis at 48 hours, was 4.7% in the cangrelor group and 5.9% in the clopidogrel group. The rates of stent thrombosis alone were 0.8% and 1.4%, respectively.
Results still favored cangrelor at 30 days, with a 15% lower risk for ischemic events and a 32% lower risk for stent thrombosis.
The rates of bleeding were equally low in both groups, at 0.16% for cangrelor-treated patients and 0.11% for clopidogrel-treated patients, although transient dyspnea occurred significantly more frequently following treatment with cangrelor than clopidogrel, at 1.2% versus 0.3%.
The results were unaffected by when the loading dose was received, ie, before or after PCI, and by which loading dose of clopidogrel was given, the researchers report.
Bhatt and colleagues comment in TheNew England Journal of Medicine that "beyond its role in reducing ischemic complications of PCI, cangrelor maybe useful in clinical situations in which ADP-receptor blockade is needed but a short-acting intravenous agent would be preferred."
But Richard Lange and David Hills, from the University of Texas Health Sciences Center in San Antonio, USA, note in an accompanying editorial that the study fails to definitely answer where cangrelor fits in the armamentarium of dual antiplatelet therapy.
They point out some concerns, including suboptimal antiplatelet effects in the clopidogrel group due to one-fourth of these patients receiving the inferior 300 mg loading dose and the variable timing of clopidogrel delivery. As a result, they say that "the routine use of this therapy [cangrelor] for all patients undergoing PCI is not yet justified."
By Lucy Piper, Senior medwireNews Reporter