Stent thrombosis with ticagrelor versus clopidogrel in patients with acute coronary syndromes: an analysis from the prospective, randomized PLATO trial

BACKGROUND We aimed to describe the effects of ticagrelor versus clopidogrel on stent thrombosis in the Platelet Inhibition and Patient Outcomes (PLATO) trial. METHODS AND RESULTS Of 18 624 patients hospitalized for acute coronary syndromes, 11 289 (61%) had at least 1 intracoronary stent. Ticagrelor reduced stent thrombosis compared with clopidogrel across all definitions: definite, 1.37% (n=71) versus 1.93% (n=105; hazard ratio [HR], 0.67; 95% confidence interval [CI], 0.50-0.90; P=0.0091); definite or probable, 2.21% (n=118) versus 2.87% (n=157; HR, 0.75; 95% CI, 0.59-0.95; P=0.017); and definite, probable, and possible, 2.94% (n=154) versus 3.77 (n=201; HR, 0.77; 95% CI, 0.62-0.95). The reduction in definite stent thrombosis was consistent regardless of acute coronary syndrome type, presence of diabetes mellitus, stent type (drug-eluting or bare metal stent), CYP2C19 genetic status, loading dose of aspirin, dose of clopidogrel before randomization, and use of glycoprotein IIb/IIIa inhibitors at randomization. The reduction in stent thrombosis with ticagrelor was numerically greater for late (>30 days; HR, 0.48; 95% CI, 0.24-0.96) and subacute (4 hours-30 days; HR, 0.60; 95% CI, 0.39-0.93) compared with acute (<24 hours; HR, 0.94; 95% CI, 0.43-2.05) stent thrombosis or for patients compliant to therapy (ie, taking blinded study treatment ≥80% of the time) compared with less compliant patients. Randomization to ticagrelor was a strong independent inverse predictor of definite stent thrombosis (HR, 0.65; 95% CI, 0.48-0.88). CONCLUSION Ticagrelor compared with clopidogrel reduces the incidence of stent thrombosis in patients with acute coronary syndromes, with consistent benefit across a broad range of patient, stent, and treatment characteristics.

Effect of ticagrelor on the outcomes of patients with prior coronary artery bypass graft surgery: insights from the PLATelet inhibition and patient outcomes (PLATO) trial

BACKGROUND Patients with prior coronary artery bypass graft surgery (CABG) who present with an acute coronary syndrome have a high risk for recurrent events. Whether intensive antiplatelet therapy with ticagrelor might be beneficial compared with clopidogrel is unknown. In this substudy of the PLATO trial, we studied the effects of randomized treatment dependent on history of CABG. METHODS Patients participating in PLATO were classified according to whether they had undergone prior CABG. The trial's primary and secondary end points were compared using Cox proportional hazards regression. RESULTS Of the 18,613 study patients, 1,133 (6.1%) had prior CABG. Prior-CABG patients had more high-risk characteristics at study entry and a 2-fold increase in clinical events during follow-up, but less major bleeding. The primary end point (composite of cardiovascular death, myocardial infarction, and stroke) was reduced to a similar extent by ticagrelor among patients with (19.6% vs 21.4%; adjusted hazard ratio [HR], 0.91 [0.67, 1.24]) and without (9.2% vs 11.0%; adjusted HR, 0.86 [0.77, 0.96]; P(interaction) = .73) prior CABG. Major bleeding was similar with ticagrelor versus clopidogrel among patients with (8.1% vs 8.7%; adjusted HR, 0.89 [0.55, 1.47]) and without (11.8% vs 11.4%; HR, 1.08 [0.98, 1.20]; P(interaction) = .46) prior CABG. CONCLUSIONS Prior-CABG patients presenting with acute coronary syndrome are a high-risk cohort for death and recurrent cardiovascular events but have a lower risk for major bleeding. Similar to the results in no-prior-CABG patients, ticagrelor was associated with a reduction in ischemic events without an increase in major bleeding.

Extent of coronary artery disease and outcomes after ticagrelor administration in patients with an acute coronary syndrome: Insights from the PLATelet inhibition and patient Outcomes (PLATO) trial.

BACKGROUND Extensive coronary artery disease (CAD) is associated with higher risk. In this substudy of the PLATO trial, we examined the effects of randomized treatment on outcome events and safety in relation to the extent of CAD. METHODS Patients were classified according to presence of extensive CAD (defined as 3-vessel disease, left main disease, or prior coronary artery bypass graft surgery). The trial's primary and secondary end points were compared using Cox proportional hazards regression. RESULTS Among 15,388 study patients for whom the extent of CAD was known, 4,646 (30%) had extensive CAD. Patients with extensive CAD had more high-risk characteristics and experienced more clinical events during follow-up. They were less likely to undergo percutaneous coronary intervention (58% vs 79%, P < .001) but more likely to undergo coronary artery bypass graft surgery (16% vs 2%, P < .001). Ticagrelor, compared with clopidogrel, reduced the composite of cardiovascular death, myocardial infarction, and stroke in patients with extensive CAD (14.9% vs 17.6%, hazard ratio [HR] 0.85 [0.73-0.98]) similar to its reduction in those without extensive CAD (6.8% vs 8.0%, HR 0.85 [0.74-0.98], Pinteraction = .99). Major bleeding was similar with ticagrelor vs clopidogrel among patients with (25.7% vs 25.5%, HR 1.02 [0.90-1.15]) and without (7.3% vs 6.4%, HR 1.14 [0.98-1.33], Pinteraction = .24) extensive CAD. CONCLUSIONS Patients with extensive CAD have higher rates of recurrent cardiovascular events and bleeding. Ticagrelor reduced ischemic events to a similar extent both in patients with and without extensive CAD, with bleeding rates similar to clopidogrel.

Cost-effectiveness of ticagrelor and generic clopidogrel in patients with acute coronary syndrome in Switzerland

QUESTION UNDER STUDY The aim of this study was to evaluate the cost-effectiveness of ticagrelor and generic clopidogrel as add-on therapy to acetylsalicylic acid (ASA) in patients with acute coronary syndrome (ACS), from a Swiss perspective. METHODS Based on the PLATelet inhibition and patient Outcomes (PLATO) trial, one-year mean healthcare costs per patient treated with ticagrelor or generic clopidogrel were analysed from a payer perspective in 2011. A two-part decision-analytic model estimated treatment costs, quality-adjusted life years (QALYs), life years and the cost-effectiveness of ticagrelor and generic clopidogrel in patients with ACS up to a lifetime at a discount of 2.5% per annum. Sensitivity analyses were performed. RESULTS Over a patient's lifetime, treatment with ticagrelor generates an additional 0.1694 QALYs and 0.1999 life years at a cost of CHF 260 compared with generic clopidogrel. This results in an Incremental Cost Effectiveness Ratio (ICER) of CHF 1,536 per QALY and CHF 1,301 per life year gained. Ticagrelor dominated generic clopidogrel over the five-year and one-year periods with treatment generating cost savings of CHF 224 and 372 while gaining 0.0461 and 0.0051 QALYs and moreover 0.0517 and 0.0062 life years, respectively. Univariate sensitivity analyses confirmed the dominant position of ticagrelor in the first five years and probabilistic sensitivity analyses showed a high probability of cost-effectiveness over a lifetime. CONCLUSION During the first five years after ACS, treatment with ticagrelor dominates generic clopidogrel in Switzerland. Over a patient's lifetime, ticagrelor is highly cost-effective compared with generic clopidogrel, proven by ICERs significantly below commonly accepted willingness-to-pay thresholds.