Comparative effects of different antiplatelet strategies in carriers of CYP2C19 loss-of-function alleles: a network meta-analysis.

BACKGROUND: Carriers of cytochrome 2C19 (CYP2C19) loss of function (LoF) alleles treated with clopidogrel have impaired drug metabolism resulting in reduced active metabolite levels, high platelet reactivity (HPR), and an increased risk of thrombotic events. Several alternative antiplatelet therapies have been proposed to overcome HPR in these patients, but their comparative effects remain poorly explored. METHODS: Randomized controlled trials (RCTs) comparing different oral antiplatelet therapies in carriers of CYP2C19 LoF alleles undergoing percutaneous coronary interventions (PCI) were included. A frequentist network meta-analysis was conducted to estimate mean difference (MD) or odds ratios (OR) and 95% confidence intervals (CI). The primary outcome was platelet reactivity assessed by VerifyNow and reported as P2Y12 reaction unit (PRU). The secondary outcome was the rate of HPR. Standard-dose of clopidogrel (75 mg daily) was used as reference treatment. RESULTS: A total of 12 RCTs testing 6 alternative strategies (i.e., clopidogrel 150 mg, prasugrel 3.75 mg, 5 mg, and 10 mg, ticagrelor 90 mg bid, and adjunctive cilostazol 100 mg bid) were included in the network. Compared with standard-dose clopidogrel, the greatest reduction in PRU was observed with prasugrel 10 mg (MD -127.91; 95% CI -141.04; -114.78) and ticagrelor 90 mg bid (MD -124.91; 95% CI -161.78; -88.04), followed by prasugrel 5 mg (MD -76.33; 95% CI -98.01; -54.65) and prasugrel 3.75 mg (MD -73.00; 95% CI -100.28; -45.72). Among other strategies, adjunctive cilostazol (MD-42.64; 95% CI -64.72; -20.57) and high-dose clopidogrel (MD -32.11; 95% CI -51.33; -12.90) were associated with a modest reduction in PRU compared with standard-dose clopidogrel. CONCLUSION: Among carriers of CYP2C19 LoF alleles undergoing PCI, standard-dose prasugrel or ticagrelor are most effective in reducing platelet reactivity, while double-dose clopidogrel and additional cilostazol showed modest effects. Reduced-dose of prasugrel may represent a balanced strategy to overcome HPR without a significant increase in bleeding. The clinical implications of these pharmacodynamic findings warrant further investigation.

P2Y12 Inhibition in Patients Requiring Oral Anticoagulation after Percutaneous Coronary Intervention: The SWAP-AC-2 Study.

BACKGROUND: Among patients treated with a novel oral anticoagulant (NOAC) undergoing percutaneous coronary intervention (PCI), combination therapy with clopidogrel (i.e., known as dual antithrombotic therapy [DAT]) is the treatment of choice. However, there are concerns for individuals with impaired response to clopidogrel. OBJECTIVES: To assess the pharmacodynamic (PD) effects of clopidogrel vs. low-dose ticagrelor in patients with impaired clopidogrel response assessed by the ABCD-GENE score. METHODS: This was a prospective, randomized PD study of NOAC-treated patients undergoing PCI. Patients with an ABCD-GENE score ≥10 (n=39), defined as having impaired clopidogrel response, were randomized to low-dose ticagrelor (n=20; 60 mg/bid) or clopidogrel (n=19; 75 mg/qd). Patients with an ABCD-GENE<10 (n=42) were treated with clopidogrel (75 mg/qd; control cohort). PD assessments at baseline and 30 days post-randomization (trough and peak) were performed to assess P2Y12 signaling [VerifyNow P2Y12 reaction units (PRU), light transmittance aggregometry (LTA), and vasodilator-stimulated phosphoprotein (VASP)]; makers of thrombosis not specific to P2Y12 signaling were also assessed. The primary endpoint was PRU (trough levels) at 30 days. RESULTS: At 30 days, PRU levels were reduced with ticagrelor-based DAT compared with clopidogrel-based DAT at trough (23.0 [3.0-46.0] vs. 154.5 [77.5-183.0]; p<0.001) and peak (6.0 [4.0-14.0] vs. 129.0 [66.0-171.0]; p<0.001). Trough PRU levels in the control arm (104.0 [35.0-167.0]) were higher than ticagrelor-based DAT (p=0.005) and numerically lower than clopidogrel-based DAT (p=0.234). Results were consistent by LTA and VASP. Markers measuring other pathways leading to thrombus formation were largely unaffected. CONCLUSIONS: In NOAC-treated patients undergoing PCI with an ABCD-gene score ≥10, ticagrelor-based DAT using a 60 mg bid regimen reduced platelet P2Y12 reactivity compared to clopidogrel-based DAT.

Effectiveness of Clopidogrel vs Alternative P2Y12 Inhibitors Based on the ABCD-GENE Score.

BACKGROUND: An ABCD-GENE (age, body mass index, chronic kidney disease, diabetes, and CYP2C19 genetic variants) score ≥10 predicts reduced clopidogrel effectiveness, but its association with response to alternative therapy remains unclear. OBJECTIVES: The aim of this study was to evaluate the association between ABCD-GENE score and the effectiveness of clopidogrel vs alternative P2Y12 inhibitor (prasugrel or ticagrelor) therapy after percutaneous coronary intervention (PCI). METHODS: A total of 4,335 patients who underwent PCI, CYP2C19 genotyping, and P2Y12 inhibitor treatment were included. The primary outcome was major atherothrombotic events (MAE) within 1 year after PCI. Cox regression was performed to assess event risk in clopidogrel-treated (reference) vs alternatively treated patients, with stabilized inverse probability weights derived from exposure propensity scores after stratifying by ABCD-GENE score and further by CYP2C19 loss-of-function (LOF) genotype. RESULTS: Among patients with scores <10 (n = 3,200), MAE was not different with alternative therapy vs clopidogrel (weighted HR: 0.89; 95% CI: 0.65-1.22; P = 0.475). The risk for MAE also did not significantly differ by treatment among patients with scores ≥10 (n = 1,135; weighted HR: 0.75; 95% CI: 0.51-1.11; P = 0.155). Among CYP2C19 LOF allele carriers, MAE risk appeared lower with alternative therapy in both the group with scores <10 (weighted HR: 0.50; 95% CI: 0.25-1.01; P = 0.052) and the group with scores ≥10 (weighted HR: 0.48; 95% CI: 0.29-0.80; P = 0.004), while there was no difference in the group with scores <10 and no LOF alleles (weighted HR: 1.03; 95% CI: 0.70-1.51; P = 0.885). CONCLUSIONS: These data support the use of alternative therapy over clopidogrel in CYP2C19 LOF allele carriers after PCI, regardless of ABCD-GENE score, while clopidogrel is as effective as alternative therapy in non-LOF patients with scores <10.

Switching from Dual Antiplatelet Therapy with Aspirin Plus a P2Y12 Inhibitor to Dual Pathway Inhibition with Aspirin Plus Vascular-Dose Rivaroxaban: The Switching Anti-Platelet and Anti-Coagulant Therapy (SWAP-AC) Study.

BACKGROUND: To date, there are no data on switching to dual pathway inhibition (DPI) patients who have completed a guideline-recommended dual antiplatelet therapy (DAPT) regimen. OBJECTIVES: To assess the feasibility of switching from DAPT to DPI and to compare the pharmacodynamic (PD) profiles of these treatments. METHODS: This was a prospective, randomized, PD study conducted in 90 patients with chronic coronary syndrome (CCS) on DAPT with aspirin (81 mg/qd) plus a P2Y12 inhibitor (clopidogrel [75 mg/qd; n = 30], ticagrelor [90 mg/bid; n = 30], or prasugrel [10 mg/qd; n = 30]). Patients in each cohort were randomized to maintain DAPT or switch to DPI (aspirin 81 mg/qd plus rivaroxaban 2.5 mg/bid). PD assessments included: VerifyNow P2Y12 reaction units; light transmittance aggregometry following stimuli with adenosine diphosphate (ADP), tissue factor (TF), and a combination of collagen, ADP, and TF (maximum platelet aggregation %); thrombin generation (TG). Assays were performed at baseline and 30 days postrandomization. RESULTS: Switching from DAPT to DPI occurred without major side effects. DAPT was associated with enhanced P2Y12 inhibition, while DPI with reduced TG. Platelet-mediated global thrombogenicity (primary endpoint) showed no differences between DAPT and DPI in the ticagrelor (14.5% [0.0-63.0] vs. 20.0% [0.0-70.0]; p = 0.477) and prasugrel (20.0% [0.0-66.0] vs. 4.0% [0.0-70.0]; p = 0.482), but not clopidogrel (27.0% [0.0-68.0] vs. 53.0% [0.0-81.0]; p = 0.011), cohorts. CONCLUSION: In patients with CCS, switching from different DAPT regimens to DPI was feasible, showing enhanced P2Y12 inhibition with DAPT and reduced TG with DPI, with no differences in platelet-mediated global thrombogenicity between DPI and ticagrelor- and prasugrel-, but not clopidogrel-, based DAPT. CLINICAL TRIAL REGISTRATION: http://www. CLINICALTRIALS: gov Unique Identifier: NCT04006288.

Bivalirudin in acute coronary syndromes.

INTRODUCTION: Bivalirudin, a bivalent direct thrombin inhibitor, has been developed to reduce bleeding without any trade-off in thrombotic events in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI). AREAS COVERED: Despite showing a superior safety profile compared with unfractionated heparin (UFH), bivalirudin is not considered the anticoagulant of choice in ACS patients undergoing PCI, mainly because of an increased rate of acute stent thrombosis (ST) shown by several randomized controlled trials (RCTs), in addition to limited availability in certain countries and increased costs. However, RCTs on bivalirudin have been characterized by several confounding factors hindering the interpretation of its safety and efficacy compared with UFH among the spectrum of ACS patients. Furthermore, a significant body of evidence has demonstrated that the risk of acute ST can be mitigated by a full-dose infusion regimen following PCI, without compromising the favorable safety profile compared to UFH. EXPERT OPINION: In light of the increased understanding of the prognostic relevance of bleeding events and the excellent safety profile of bivalirudin, recent trial evidence may allow for this anticoagulant agent to reemerge and have a more prominent role in the management of ACS patients undergoing PCI.

Effect of lipid-lowering therapy on platelet reactivity in patients treated with and without antiplatelet therapy.

Circulating lipoproteins may interact with platelets, increasing platelet sensitivity to aggregating agonists and their tendency towards activation and thrombus formation. In particular, patients with hypercholesterolemia exhibit a higher degree of platelet reactivity compared to normolipidemic. Moreover, accruing evidence report that lipid-lowering therapies can reduce thrombus formation, particularly in the absence of concomitant antiplatelet therapy. However, the underlying biological mechanism(s) explaining these clinical observations are not completely understood. Baseline platelet reactivity and high on-treatment platelet reactivity while on antiplatelet therapy (e.g., aspirin and clopidogrel) are associated with poor clinical outcomes. Therefore, strategies to reduce baseline platelet reactivity or improve the pharmacodynamic profile of antiplatelet therapies are an unmet clinical need. The potential use of lipid-lowering therapies for optimizing platelet reactivity provides several advantages as there is strong evidence that reducing circulating lipoproteins can improve clinical outcomes, and they may avoid the need for potent antiplatelet therapies that, although more effective, are associated with increased bleeding risk. This review will provide a systematic overview of the effects of lipid-lowering therapy on platelet reactivity in patients treated with and without antiplatelet therapy. We will focus on the potential biological mechanism(s) of action and the effect of statins, ezetimibe, proprotein convertase subtilisin/kexin 9 inhibitors, omega-3 fatty acids, and recombinant high-density lipoprotein on platelet reactivity. Ultimately, we will assess the current gaps in the literature and future perspective in the field.

Switching From Cangrelor to Prasugrel in Patients Undergoing Percutaneous Coronary Intervention: The Switching Antiplatelet-6 (SWAP-6) Study.

BACKGROUND: A drug-drug interaction (DDI) may occur when transitioning from intravenous P2Y12 inhibition with cangrelor to oral P2Y12 inhibition with prasugrel. However, this has never been tested in patients undergoing percutaneous coronary intervention (PCI). OBJECTIVES: This study sought to rule out a DDI when cangrelor and prasugrel are concomitantly administered in PCI patients. METHODS: SWAP-6 (Switching Antiplatelet-6) was a prospective, randomized, 3-arm, open-label pharmacokinetic (PK) and pharmacodynamic (PD) study. Patients (N = 77) were randomized to 1) prasugrel only at the start of PCI, 2) cangrelor plus prasugrel concomitantly at the start of PCI, or 3) cangrelor at the start of PCI plus prasugrel at the end of infusion. Cangrelor infusion was maintained for 2 hours. PK/PD assessments were performed at baseline and 6 time points postrandomization. The primary endpoint was noninferiority in VerifyNow (Werfen) P2Y12 reaction units measured at 4 hours after randomization between cangrelor plus prasugrel concomitantly administered vs prasugrel only. PK assessments included plasma levels of the active metabolite of prasugrel. RESULTS: Compared with prasugrel, cangrelor further enhances P2Y12 inhibitory effects. At 4 hours postrandomization, P2Y12 reaction unit levels were significantly lower with prasugrel only compared to cangrelor and prasugrel concomitantly administered (least squares means difference = 130; 95% CI: 85-176), failing to meet the prespecified noninferiority margin. Findings were corroborated by multiple PD assays. The active metabolite of prasugrel levels were not affected by concomitant administration of cangrelor and were low at the end of cangrelor infusion. CONCLUSIONS: In patients undergoing PCI, concomitant administration of prasugrel with cangrelor leads to a marked increase in platelet reactivity after stopping cangrelor infusion, supporting the presence of a DDI. (Switching Antiplatelet Therapy-6 [SWAP-6]; NCT04668144).

Novel Tissue Factor Inhibition for Thromboprophylaxis in COVID-19: Primary Results of the ASPEN-COVID-19 Trial.

BACKGROUND: Thrombo-inflammation is central to COVID-19-associated coagulopathy. TF (tissue factor), a driver of disordered coagulation and inflammation in viral infections, may be a therapeutic target in COVID-19. The safety and efficacy of the novel TF inhibitor rNAPc2 (recombinant nematode anticoagulation protein c2) in COVID-19 are unknown. METHODS: ASPEN-COVID-19 was an international, randomized, open-label, active comparator clinical trial with blinded end point adjudication. Hospitalized patients with COVID-19 and elevated D-dimer levels were randomized 1:1:2 to lower or higher dose rNAPc2 on days 1, 3, and 5 followed by heparin on day 8 or to heparin per local standard of care. In comparisons of the pooled rNAPc2 versus heparin groups, the primary safety end point was major or nonmajor clinically relevant International Society of Thrombosis and Haemostasis bleeding through day 8. The primary efficacy end point was proportional change in D-dimer concentration from baseline to day 8, or discharge if before day 8. Patients were followed for 30 days. RESULTS: Among 160 randomized patients, median age was 54 years, 43.1% were female, and 38.8% had severe baseline COVID-19. There were no significant differences between rNAPc2 and heparin in bleeding or other safety events. Overall, median change in D-dimer was -16.8% (interquartile range, -45.7 to 36.8; P=0.41) with rNAPc2 treatment and -11.2% (-36.0 to 34.4; P=0.91) with heparin (Pintergroup=0.47). In prespecified analyses, in severely ill patients, D-dimer levels tended to increase more within the heparin (median, 29.0% [-14.9 to 145.2]; P=0.02) than the rNAPc2 group (median, 25.9% [-49.1 to 136.4]; P=0.14; Pintergroup=0.96); in mildly ill patients, D-dimer levels were reduced within each group with a numerically greater reduction with rNAPc2 versus heparin (rNAPc2 median, -32.7% [-44.7 to 4.3]; P=0.007 and heparin median, -16.8% [-36.0 to 0.5]; P=0.008, Pintergroup=0.34). CONCLUSIONS: rNAPc2 treatment in hospitalized patients with COVID-19 was well tolerated without excess bleeding or serious adverse events but did not significantly reduce D-dimer more than heparin at day 8. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04655586.

Defining Strategies of Modulation of Antiplatelet Therapy in Patients With Coronary Artery Disease: A Consensus Document from the Academic Research Consortium.

Antiplatelet therapy is the mainstay of pharmacologic treatment to prevent thrombotic or ischemic events in patients with coronary artery disease treated with percutaneous coronary intervention and those treated medically for an acute coronary syndrome. The use of antiplatelet therapy comes at the expense of an increased risk of bleeding complications. Defining the optimal intensity of platelet inhibition according to the clinical presentation of atherosclerotic cardiovascular disease and individual patient factors is a clinical challenge. Modulation of antiplatelet therapy is a medical action that is frequently performed to balance the risk of thrombotic or ischemic events and the risk of bleeding. This aim may be achieved by reducing (ie, de-escalation) or increasing (ie, escalation) the intensity of platelet inhibition by changing the type, dose, or number of antiplatelet drugs. Because de-escalation or escalation can be achieved in different ways, with a number of emerging approaches, confusion arises with terminologies that are often used interchangeably. To address this issue, this Academic Research Consortium collaboration provides an overview and definitions of different strategies of antiplatelet therapy modulation for patients with coronary artery disease, including but not limited to those undergoing percutaneous coronary intervention, and consensus statements on standardized definitions.

Clinical and Pre-Clinical Pharmacokinetics and Pharmacodynamics of Bentracimab.

Antiplatelet agents are among the most frequently used medications in cardiovascular medicine. Although in patients with atherosclerotic disease manifestations, in particular those treated by percutaneous coronary intervention, antiplatelet agents are beneficial for the prevention of ischemic events, they inevitably increase the risk of bleeding. Furthermore, 5-15% of patients treated by percutaneous coronary intervention may need a surgical procedure within 2 years, creating challenges to safe and effective antiplatelet drug management. Importantly, major spontaneous or procedural-related bleedings are associated with increased hospital admission, length, costs, and poor prognosis. Although the effects of other antithrombotic therapies, such as direct oral anticoagulants, can be reversed by approved specific agents, there are no approved reversal agents for any antiplatelet drugs. The fact that many antiplatelet agents, such as aspirin and thienopyridines (i.e., clopidogrel and prasugrel), bind irreversibly to their targets represents a challenge for the development of a drug-specific reversal agent. In contrast, ticagrelor is a non-thienopyridine with a plasma half-life of 7-9 h that reversely binds the P2Y12 receptor producing potent signaling blockage. In 2015, bentracimab (also known as PB2452 or MEDI2452), a neutralizing monoclonal antibody fragment that binds free plasma ticagrelor and its major active metabolite, was identified. This systematic overview provides a comprehensive summary of the drug development program of bentracimab, focusing on its pharmacodynamic, pharmacokinetic, and safety profiles.

Factor XI Inhibitors in Early Clinical Trials: A Meta-analysis.

BACKGROUND: Phase II randomized controlled trials (RCTs) on factor(F)XI inhibitors have shown promising results but they were burdened by low statistical power for clinical outcomes. METHODS: We performed a systematic review and meta-analysis of RCT comparing FXI inhibitors versus other anticoagulants (enoxaparin or direct oral anticoagulants, DOACs) or versus placebo on top of antiplatelet therapy. RESULTS: Eight RCTs testing FXI inhibitors (ISIS 416858, osocimab, abelacimab, milvexian, asundexian) and enrolling 9,216 patients were included. Compared with enoxaparin, FXI inhibitors were associated with reduced any-bleeding (risk ratio [RR]: 0.49, 95% confidence interval [CI]: 0.31-0.77), no difference in major bleeding (RR: 0.96, 95% CI: 0.41-2.28), and reduced trial-defined efficacy endpoint (RR: 0.62, 95% CI: 0.49-0.79), the latter driven by the high-dose regimens. Compared with DOACs, FXI inhibitors were associated with a trend toward reduced any-bleeding (RR: 0.66, 95% CI: 0.31-1.38) and no difference in major bleeding (RR: 1.03, 95% CI: 0.22-4.78) or in trial-defined efficacy endpoint (RR: 1.23, 95% CI: 0.88-1.70). Compared with placebo, FXI inhibitors were associated with increased any-bleeding (RR: 1.25, 95% CI: 1.08-1.43) and a trend toward increased major bleeding (RR: 1.21, 95% CI: 0.75-1.93), both driven by high-dose regimens, with no difference in trial-defined efficacy endpoint (RR: 1.02, 95% CI: 0.92-1.13). CONCLUSION: Results of this meta-analysis on FXI inhibitors suggest increased safety and efficacy compared with enoxaparin and modest increased safety compared with DOACs. The use of FXI inhibitors in adjunct to antiplatelet therapy versus placebo appears to be associated with a dose-dependent increase in bleeding without any difference in efficacy. STUDY REGISTRATION: This study is registered in PROSPERO (CRD42022367706).

Impact of evolocumab on the pharmacodynamic profiles of clopidogrel in patients with atherosclerotic cardiovascular disease: a randomised, double-blind, placebo-controlled study.

BACKGROUND: The impact of intense low-density lipoprotein cholesterol (LDL-C) reduction using a proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor on profiles of platelet reactivity has yet to be explored. AIMS: Our aim was to investigate the effects of the PCSK9 inhibitor, evolocumab, on platelet reactivity in patients with atherosclerotic cardiovascular disease (ASCVD) on clopidogrel treatment. METHODS: This was a prospective, randomised, double-blind, placebo-controlled pharmacodynamic study in patients with ASCVD on clopidogrel treatment and with LDL-C levels ≥70 mg/dL despite a maximally tolerated statin dose. Patients were stratified according to levels of platelet reactivity using VerifyNow P2Y12 reactivity units (PRU) into high platelet reactivity (HPR; PRU >208) or normal platelet reactivity (NPR; PRU >85 and ≤208). Each cohort was randomised to receive evolocumab 420 mg or placebo. The primary endpoint was the difference in PRU at 30 days. RESULTS: A total of 84 patients (HPR, n=37 [19 evolocumab vs 18 placebo]; NPR, n=47 [22 evolocumab vs 25 placebo]) were included. Evolocumab significantly reduced LDL-C compared to placebo at 14 (p<0.001) and 30 (p=0.001) days. At 14 days, PRU levels were significantly lower with evolocumab compared to placebo in the HPR (218.2±29.7 vs 246.6±35.2; p=0.017), but not in the NPR cohort (141.2±42.8 vs 148.2±41.7; p=0.578). At 30 days, there were no significant differences in PRU in the HPR (219.3±38.3 vs 240.9±51.8; p=0.161) or NPR (141.5±54.3 vs 158.6±40.8; p=0.229) cohorts. CONCLUSIONS: Compared to placebo, evolocumab in adjunct to statin therapy did not significantly reduce platelet reactivity at 30 days in ASCVD patients on clopidogrel treatment despite intense LDL-C reduction. ClinicalTrials.gov: NCT03096288.

Influence of body weight and body mass index on the chronic pharmacokinetic and pharmacodynamic responses to clinically available doses of ticagrelor in patients with chronic coronary syndromes.

Ticagrelor has multiple indications, including for some patients with chronic coronary syndromes (CCS) at high risk of ischaemic events. Body mass can potentially affect pharmacodynamics (PD) and pharmacokinetics (PK). We investigated the influence of body mass (range 53-172 kg, 20.8-46.9 kg/m2) on PD/PK in 221 CCS patients receiving ticagrelor 60 mg or 90 mg twice-daily (BD) during two randomised-controlled trials. Correlations between body weight (BW) or body mass index (BMI) and PD/PK measurements obtained during maintenance treatment at trough ('pre-dose') and peak effect ('post-dose') were assessed. BW and BMI correlated with P2Y12 reactivity units at pre-dose (e.g. BW:R = 0.26, p = 0.008) but not post-dose timepoints. BW affected ticagrelor active metabolite (TAM) levels (e.g. 60 mg BD, post-dose:R = -0.39, p < 0.0001) and there was evidence of an inverse power law relationship between BW and TAM-to-ticagrelor ratio. PK with ticagrelor 60 mg correlated significantly with BMI. BW and BMI did not affect the chance of high platelet reactivity, which remained very low across the whole cohort. There was no difference in PRU between the two doses of ticagrelor within each weight or BMI group. Body mass has modest effects on the PK/PD response to ticagrelor in patients with CCS but currently-used regimens appear adequate across the range of BW/BMI studied.

Dual pathway inhibition in atherothrombosis prevention: yes, now we can!

Despite ongoing developments, prevention and treatment of atherothrombotic cardiovascular disease remains a common challenge. Antithrombotic options for cardiocerebrovascular disease prevention involves a choice between dual antiplatelet therapy (DAPT) and dual pathway inhibition (DPI), which includes an antiplatelet agent and a reduced dose anticoagulant agent. In selected patients at high risk of event and low risk of bleeding, especially those undergoing recent and complex coronary revascularization using drug-eluting stents (DES) ("revascularization-driven effect"), DAPT is superior to single antiplatelet therapy with aspirin. DPI involves a wider potential range of treatment and is superior to single antiplatelet therapy with aspirin, particularly in patients with atherothrombotic involvement in different vascular beds both previously revascularized and not ("no revascularization-driven effect"). After nearly thirty years of randomized trials and observational registries, we have sufficient data to customize antithrombotic therapy in patients at high cardiovascular risk. Therefore, "atherothrombosis stakeholders" must identify the right patient for the right therapy to ensure high levels of efficacy and safety with the best of current therapeutic opportunities.

Role of platelet function and genetic testing in patients undergoing percutaneous coronary intervention.

Dual antiplatelet therapy (DAPT) represents the standard of care for patients undergoing percutaneous coronary intervention (PCI). Increasing evidence indicates that a "one-size-fits-all" approach with the use of a standard DAPT regimen for all patients undergoing PCI could lead to either suboptimal efficacy or prohibitively high bleeding in specific cohorts of patients. Moreover, the broad interindividual variability in response to P2Y12 inhibitors can impact outcomes and resource utilization. Among the strategies proposed to provide a more balanced trade-off between bleeding and ischemic events at a single patient level, a guided selection of P2Y12 inhibitors, by using platelet function or genetic testing, has shown promising results. In this review, we provide a focused summary of the rationale and evidence on the use of platelet function and genetic testing-guided antiplatelet therapy, and we explore the implications for their use in the modern setting of patients undergoing PCI.

Cangrelor in Patients With Coronary Artery Disease Pretreated With Ticagrelor: The Switching Antiplatelet (SWAP)-5 Study.

BACKGROUND: There are no studies specifically designed to rule out a drug-drug interaction (DDI) when cangrelor is used among patients who have been pretreated with ticagrelor. OBJECTIVES: This study sought to rule out a DDI among cangrelor-treated patients who have been pretreated with ticagrelor. METHODS: In this prospective, randomized, double-blind, placebo-controlled, crossover, pharmacokinetic (PK) and pharmacodynamic (PD) study, patients with coronary artery disease (N = 20) were pretreated with a 180-mg ticagrelor loading dose and after 1 hour randomized to placebo or cangrelor (bolus and infusion for 2 hours). Patients crossed over after 1 to 4 weeks of washout. PK analysis included ticagrelor plasma levels and its active metabolite. PD assessments included VerifyNow P2Y12 reaction units (PRU), light transmittance aggregometry, vasodilator-stimulated phosphoprotein, and Total Thrombus-Formation Analysis System. PK/PD assessments were performed at 7 time points. RESULTS: Compared with placebo, adding cangrelor to patients pretreated with ticagrelor resulted in a significant reduction in PRU at 30 minutes and 1 hour after starting infusion. At 2 hours after stopping cangrelor/placebo infusion, PRU were low and similar in both groups (16.9 vs 12.6; mean difference: 4.3; 95% CI: -28.6 to 37.3), meeting the noninferiority primary endpoint (predefined noninferiority margin 45 PRU). Consistent findings were shown with all PD assays. PK tracked PD findings with no differences between groups in plasma levels of ticagrelor and its metabolite. CONCLUSIONS: Compared with placebo, the use of cangrelor in patients pretreated with ticagrelor results in enhanced platelet inhibition with no differences in PK/PD profiles after discontinuation of drug infusion indicating the absence of a DDI. (PD and PK Profiles of Switching Between Cangrelor and Ticagrelor Following Ticagrelor Pre-treatment [SWAP-5]; NCT04634162).

Dual pathway inhibition in patients with atherosclerotic disease: pharmacodynamic considerations and clinical implications.

INTRODUCTION: The persistence of elevated rates of ischemic recurrences despite the use of antiplatelet therapy among patients with atherosclerotic disease together with the understanding of the pivotal role of coagulation in the thrombo-inflammatory processes involved in the pathogenesis of atherosclerosis and its complications has fostered the development of treatments targeting both platelets and coagulation, a strategy known as dual-pathway inhibition (DPI). AREAS COVERED: In this review we discuss the recent advancements in the understanding of the interplay between coagulation, platelets and inflammation involved in the pathophysiology of atherosclerosis and atherothrombosis, as the rationale for the implementation of a DPI strategy. We also discuss the available pharmacodynamic (PD) evidence and clinical implications with the use of DPI in patients with atherosclerotic disease. EXPERT OPINION: The implementation of a DPI by adding the so-called 'vascular dose of rivaroxaban' (i.e. 2.5 mg bis in die), on top of antiplatelet therapy has consistently been associated with reduced levels of thrombin generation in PD studies and with reduced ischemic event rates at the cost of increased bleeding compared to antiplatelet therapy alone. Further research is warranted to best define patients in whom a DPI regimen has the best safety and efficacy profile.

Evaluation of Potential Racial Disparities in CYP2C19-Guided P2Y12 Inhibitor Prescribing After Percutaneous Coronary Intervention.

Black patients suffer worse outcomes after percutaneous coronary intervention (PCI) than White patients. Inequities in antiplatelet prescribing may contribute to this health disparity. We compared P2Y12 inhibitor prescribing by race following CYP2C19 genotyping to guide antiplatelet therapy selection after PCI. Patients from 9 sites that performed clinical CYP2C19 genotyping after PCI were included. Alternative therapy (e.g., prasugrel or ticagrelor) was recommended for CYP2C19 no-function allele carriers, in whom clopidogrel is predicted to be less effective. The primary outcome was choice of P2Y12 inhibitor (clopidogrel vs. alternative therapy) based on genotype. Of 3,342 patients included, 2,448 (73%) were White, and 659 (20%) were Black. More Black than White patients had a no-function allele (34.3% vs. 29.7%, P = 0.024). At hospital discharge following PCI, 44.2% of Black and 44.0% of White no-function allele carriers were prescribed alternative therapy. At the time of the last follow-up within 12 months, numerically fewer Black (51.8%) than White (56.7%) no-function allele carriers were prescribed alternative therapy (P = 0.190). However, the difference was not significant after accounting for other factors associated with P2Y12 inhibitor selection (odds ratio 0.79, 95% confidence interval 0.58-1.08). Alternative therapy use did not differ between Black (14.3%) and White (16.7%) patients without a no-function allele (P = 0.232). Among real-world patients who received CYP2C19 testing after PCI, P2Y12 inhibitor prescribing rates did not differ between Black and White patients. Our data suggest an absence of racial disparity in genotype-guided antiplatelet prescribing among patients receiving CYP2C19 testing.