Rivaroxaban monotherapy versus combination therapy according to patient risk of stroke and bleeding in atrial fibrillation and stable coronary disease: AFIRE trial subanalysis.

BACKGROUND: In the AFIRE trial, rivaroxaban monotherapy was noninferior to combination therapy with rivaroxaban and an antiplatelet agent for thromboembolic events or death, and superior for major bleeding in patients with atrial fibrillation (AF) and stable coronary artery disease. Little is known about impacts of stroke and bleeding risks on the efficacy and safety of rivaroxaban monotherapy. METHODS: In this subanalysis of the AFIRE trial, we assessed the risk of stroke and bleeding by the CHADS2, CHA2DS2-VASc, and HAS-BLED scores. The primary efficacy end point was the composite of stroke, systemic embolism, myocardial infarction (MI), unstable angina requiring revascularization, or death from any cause. The primary safety end point was major bleeding defined by the International Society on Thrombosis and Haemostasis. RESULTS: Rivaroxaban monotherapy significantly reduced the primary efficacy and safety end points with no evidence of differential effects by stroke risk (CHADS2, p for interaction = 0.727 for efficacy, 0.395 for safety; CHA2DS2-VASc, p for interaction = 0.740 for efficacy, 0.265 for safety) or bleeding risk (HAS-BLED, p for interaction = 0.581 for efficacy, 0.225 for safety). There was also no evidence of statistical heterogeneity across patient risk categories for other end points; stroke or systemic embolism, ischemic stroke, hemorrhagic stroke, MI, MI or unstable angina, death from any cause, any bleeding, or net adverse clinical events. CONCLUSIONS: The advantages of rivaroxaban monotherapy compared with those of combination therapy with respect to all prespecified end points, including thromboembolism, bleeding, and mortality were similar across patients with AF and stable coronary artery disease, irrespective of their risk for stroke and bleeding. CLINICAL TRIAL REGISTRATION: UMIN Clinical Trials Registry number, UMIN000016612, and ClinicalTrials.gov number, NCT02642419.

Comparative Effectiveness and Safety Analysis of Dual Antiplatelet Therapies Within an Integrated Delivery System.

BACKGROUND: Dual antiplatelet therapy is a mainstay of care for percutaneous coronary intervention (PCI) patients; however, uncertainty exists in real-world practice about comparative effectiveness and safety outcomes. OBJECTIVE: To evaluate outcomes of different oral P2Y12 inhibitors in PCI patients. METHODS: We retrospectively studied patients treated between July 1, 2010, and December 31, 2013. Patients received clopidogrel, prasugrel, ticagrelor, or more than 1 antiplatelet (switch) during PCI. Outcomes were evaluated for major adverse cardiovascular events (MACE) and bleeding at 1 year. Propensity score matching with Cox proportional hazards analysis was used to determine predictors of MACE and bleeding. RESULTS: A total of 8127 patients were included: clopidogrel (n = 6872), prasugrel (n = 605), ticagrelor (n = 181), and switch (n = 469). Treatment with prasugrel was associated with the lowest risk of MACE using multivariate regression (odds ratio [OR] = 0.57; 95% CI = 0.36-0.92; P = 0.02). In the propensity score-matched analysis, only the prasugrel group was associated with a lower risk of MACE compared with the clopidogrel group. Clopidogrel was associated with the lowest risk of major bleeding using multivariate regression (OR = 0.64; 95% CI = 0.42-0.98; P = 0.042). Both ticagrelor (hazard ratio [HR] = 2.00; 95% CI = 1.11-3.59) and the switch groups (HR = 1.65; 95% CI = 1.09-2.50) were associated with a greater risk of major bleeding compared with clopidogrel. However, no differences were found in the propensity score-matched analysis. CONCLUSIONS: Dual antiplatelet therapies differed in both MACE and bleeds in a real-world setting of PCI. Prasugrel was associated with fewer MACE, whereas clopidogrel had fewer major bleeding events.

A randomized trial assessing the impact of three different glycoprotein IIb/IIIa antagonists on glycoprotein IIb/IIIa platelet receptor inhibition and clinical endpoints in patients with acute coronary syndromes.

AIMS: To compare three glycoprotein IIb/IIIa receptor antagonists (GPIs) in terms of platelet inhibition and major adverse cardiac events (MACEs), and assess the rate of bleeding and MACEs between GPIs and coadministered P2Y12 agents. METHODS: Eighty-three acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) with planned GPI use were randomized to receive high-dose bolus tirofiban, double-bolus eptifibatide, or abciximab followed by a 12-hour infusion. Glycoprotein IIb/IIIa platelet receptor inhibition was measured at baseline and at 10 minutes, 1 hour, and 24 hours postbolus dose. Major adverse cardiac events and bleeding complications at 30 days were documented. The incidence of MACEs and bleeding in patients receiving ticagrelor or prasugrel were compared to those given clopidogrel. RESULTS: There were no statistically significant differences in platelet inhibition between GPIs at 10 minutes (P=.085) and 1 hour (P=.337). At 24 hours, abciximab achieved statistically significantly higher median [interquartile range] platelet inhibition (75 [65-88]%) compared to tirofiban (28 [3-56]%; P<.0001) and eptifibatide (44 [31-63]%; P=.007). There were no differences in bleeding or MACEs depending on GPI or P2Y12 inhibitor administered. CONCLUSIONS: Glycoprotein receptor inhibitors achieve similar levels of platelet inhibition at 10 minutes and 1 hour; however, abciximab maintains this benefit 24 hours after bolus dose. We did not witness an increased rate of bleeding in patients given new potent P2Y12 inhibitors and a GPI in the modern era.

Solid cancers after antiplatelet therapy: Confirmations, controversies, and challenges.

The role of anticoagulants and antiplatelet agents in tumour growth and prognosis is not new, and currently under intense investigation. Some randomised data strongly suggest that this association exists, but it is complex, and not necessarily pointed at the same direction. The potential mechanisms responsible for such harmful association include a direct hazard of novel antithrombotics on cancer, indirect promotion of tumour growth, easier metastatic dissemination due to instability of platelet-tumour cell aggregates, or/and inability to keep cancer cells locally in situ are considered. The latest randomised evidence ultimately rejected the drug-specific cancer risks, clearly indicating the class-effect. In lay terms "cancers follow bleeding", which seems to be true for antithrombotic agents in general. Significant excess of solid cancers which was similar after prasugrel in TRITON, and with vorapaxar in TRACER trials was confirmed by the FDA reviews. Later, extra cancer deaths reported following clopidogrel and prasugrel in DAPT, and after ticagrelor in PEGASUS are also of concern. However, there are remaining controversies with regard to published cancer risks after ticagrelor (PLATO), or another vorapaxar trial (TRA2P), while full disclosure of separate clopidogrel and prasugrel cancer data in DAPT is still lacking. In short, if we apply moderate antiplatelet strategies for over two years, or aggressive regimens including triple therapy for much less than one year, the solid cancer risks emerge. Currently, more delicate platelet inhibition, and shorter exposure to dual oral antiplatelet agents should prevail.