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.

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.

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).

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.

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).

1157 WITCHING 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

Aims

To assess the feasibility of switching from dual antiplatelet therapy (DAPT) to dual pathway inhibition (DPI) and to compare the pharmacodynamic (PD) profiles of these treatment regimens.

Methods and results

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, and a combination of collagen, ADP, and TF (CATF, maximum platelet aggregation %); thrombelastograph coagulation analyzer; thrombin generation (TG). Assays were performed at baseline (on DAPT) and 30 days post-randomization (trough and peak). 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.

Pharmacokinetic and pharmacodynamic profiles of a novel phospholipid-aspirin complex liquid formulation and low dose enteric-coated aspirin: results from a prospective, randomized, crossover study

Low dose enteric-coated aspirin (EC-ASA) is routinely used for secondary cardiovascular event prevention. However, absorption of EC tablets is poor, which can result in subtherapeutic antiplatelet effects. Phospholipid-aspirin liquid filled capsules (PL-ASA) are a novel FDA-approved immediate-release formulation designed to reduce gastrointestinal (GI) injury by limiting direct contact with the stomach lining. We compared the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of PL-ASA versus EC-ASA at a low dose. This randomized, open-label, crossover study assessed PK and PD following a single 81-mg dose of PL-ASA versus EC-ASA under fasting conditions in 36 volunteers without cardiovascular disease between 18 and 75 years of age. Volunteers were randomly assigned 1:1 to either PL-ASA then EC-ASA or vice versa with a minimum 14-day washout. Assessments included PK parameters for acetylsalicylic acid and salicylic acid, platelet aggregation in response to arachidonic acid (AA), and serum thromboxane B2 (TxB₂) assessments over 24 h. PL-ASA was rapidly absorbed. PL-ASA reached T_max 3 h earlier (1.01 vs. 4.00 h, p < 0.0001), with almost double the C_max (720 vs. 368 ng/mL, p < 0.0001) and overall 44% higher exposure of acetylsalicylic acid (AUC_0-t: 601 vs. 416 h*ng/mL, p = 0.0013) compared with EC-ASA. Within 1 h of dosing, PL-ASA achieved significantly lower residual platelet aggregation, which persisted for the full 24 h (median AA-LTA was 47% with PL-ASA vs. 80.5% with EC-ASA; p = 0.0022 at hour-24). Treatment with PL-ASA also resulted in significantly lower serum TxB₂ concentrations at each time point compared with EC-ASA (all p-values < 0.05). PL-ASA resulted in faster and more complete aspirin absorption paralleled by more prompt and potent platelet inhibition compared with EC-ASA after a single 81 mg dose. PL-ASA represents an attractive novel aspirin formulation for the secondary prevention of cardiovascular events.

Clinical Trial Registration ClinicalTrials.gov identifier: NCT04811625.

Platelet P2Y12 inhibiting therapy in adjunct to vascular dose of rivaroxaban or aspirin: A pharmacodynamic study of dual pathway inhibition versus dual antiplatelet therapy

AIM

Dual-pathway inhibition (DPI) by adding a vascular dose of rivaroxaban to a single antiplatelet agent has emerged as a promising antithrombotic strategy. However, in most studies the antiplatelet agent of choice used in adjunct to a vascular dose of rivaroxaban was aspirin, and data with a P2Y12 inhibitor and how this DPI regimen compares with standard dual antiplatelet therapy (DAPT) is limited.

METHODS AND RESULTS

This investigation was a sub-study analysis conducted in selected cohorts of patients with stable atherosclerotic disease enrolled from a larger prospective, open-label, parallel-group pharmacodynamics (PD) study. We analyzed data from 40 patients treated with either clopidogrel or ticagrelor-based DAPT first, and clopidogrel or ticagrelor-based DPI thereafter. PD measures explored key pathways involved in thrombus formation and included markers of: 1) P2Y12 reactivity, 2) platelet-mediated global thrombogenicity, 3) cyclooxygenase-1 activity, 3) TRAP-induced platelet aggregation; 4) tissue factor (TF)-induced platelet aggregation, and 5) thrombin generation. As compared to DAPT, on a background of the same P2Y12 inhibitor (clopidogrel or ticagrelor), DPI was associated with reduced thrombin generation, increased markers of cyclooxygenase-1 activity and TRAP-induced platelet aggregation and no differences in markers of P2Y12 signaling, platelet-mediated global thrombogenicity and TF-induced platelet aggregation. In an analysis according to P2Y12 inhibitor type, ticagrelor reduced markers of platelet-mediated global thrombogenicity, P2Y12 signaling and rates of high platelet reactivity compared to clopidogrel.

CONCLUSIONS

Compared to DAPT with aspirin and a P2Y12 inhibitor, the use of a P2Y12 inhibitor in adjunct to a vascular dose of rivaroxaban as part of a DPI strategy is associated with similar effects on platelet-mediated global thrombogenicity but reduced thrombin generation. A DPI strategy with ticagrelor is associated with enhanced antithrombotic efficacy, the clinical implications of which warrant larger scale investigations.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03718429.

Pharmacodynamic profiles of dual-pathway inhibition with or without clopidogrel vs dual antiplatelet therapy in patients with atherosclerotic disease

AIM

Inhibition of thrombin-mediated signaling processes using a vascular dose of rivaroxaban in adjunct to antiplatelet therapy, known as dual-pathway inhibition (DPI), reduces atherothrombotic events in patients with stable atherosclerotic disease. However, there are limited data on the pharmacodynamic (PD) effects of this strategy.

METHODS AND RESULTS

This investigation was conducted in selected cohorts of patients (n=40) with stable atherosclerotic disease enrolled within a larger prospective PD study who were treated with either aspirin plus clopidogrel (DAPT), aspirin plus rivaroxaban 2.5 mg/bid (DPI) or DAPT plus rivaroxaban 2.5 mg/bid. Multiple PD assays assessing of markers of thrombosis were used. PD endpoints included platelet-mediated global thrombogenicity measured by light transmittance aggregometry (LTA) following stimuli with CATF [collagen-related peptide +adenosine diphosphate (ADP) +tissue factor (TF)], markers of P2Y12 reactivity, markers of platelet aggregation using LTA following several stimuli (arachidonic acid, ADP, collagen, TF, and TRAP), thrombin generation and thrombus formation. There was no difference in platelet-mediated global thrombogenicity between groups. Rivaroxaban significantly reduced thrombin generation and was associated with a trend towards reduced TF-induced platelet aggregation. Clopidogrel-based treatments reduced markers of P2Y12 signaling and TRAP-induced platelet aggregation. There were no differences between groups on markers of cyclooxygenase-1 mediated activity.

CONCLUSIONS

Compared with DAPT, DPI does not result in any differences in platelet-mediated global thrombogenicity, but reduces thrombin generation. These PD observations support that modulating thrombin generation by means of factor Xa inhibition in adjunct to antiplatelet therapy provides effective antithrombotic effects, supporting the efficacy and safety findings of DPI observed in clinical.

10 Pharmacodynamic profiles of aspirin versus dual-pathway inhibition with either aspirin or clopidogrel among patients with stable atherosclerotic disease

Aims

Inhibition of thrombin-mediated signalling processes using a vascular dose of rivaroxaban in adjunct to single antiplatelet therapy, known as dual-pathway inhibition (DPI), reduces atherothrombotic events in patients with stable atherosclerotic disease. However, there is limited data on the pharmacodynamic (PD) effects of this strategy.

Methods

This investigation was conducted in selected cohorts of patients (n = 40) with stable atherosclerotic disease enrolled from a larger prospective, open-label, parallel-group PD study who were treated with either aspirin, aspirin plus rivaroxaban 2.5 mg/bid or clopidogrel plus rivaroxaban 2.5 mg/bid. Multiple PD assays providing a comprehensive assessment of markers of thrombosis were used. The primary endpoint was the comparison between groups of platelet-mediated global thrombogenicity by light transmittance aggregometry (LTA) following stimuli with collagen-related peptide + adenosine diphosphate + tissue factor (CATF).

Results

There were no differences in the primary endpoint between aspirin vs. aspirin plus rivaroxaban 2.5 mg/bid (P = 0.110), aspirin vs. clopidogrel plus rivaroxaban 2.5 mg/bid (P = 0.611) or aspirin plus rivaroxaban 2.5 mg/bid vs. clopidogrel plus rivaroxaban 2.5 mg/bid (P = 0.315). Rivaroxaban-based treatments significantly reduced markers of thrombin generation (peak thrombin and thrombin velocity index). Clopidogrel-based treatments reduced markers of P2Y12 signalling (LTA ADP 20 max and VerifyNow). Aspirin-based treatments reduced markers of markers of cyclooxygenase-1 activity (LTA collagen).

Conclusions

Compared with aspirin alone, DPI with either aspirin or clopidogrel might provide superior ischaemic protection by targeting pathways alternative to those affected by antiplatelet agents with only a moderate trade-off in bleeding as supported by similar platelet-mediated global thrombogenicity between treatments.

Impact Of Chronic Kidney Disease On The Pharmacodynamic And Pharmacokinetic Effects Of Ticagrelor In Patients With Diabetes Mellitus And Coronary Artery Disease

AIMS

Patients with diabetes mellitus (DM) and chronic kidney disease (CKD) are at increased risk of atherothrombotic events. Ticagrelor reduces ischaemic events compared to clopidogrel, with the greatest risk reduction in patients with both DM and CKD. How CKD status affects the pharmacodynamic (PD) and pharmacokinetic (PK) profiles of different ticagrelor maintenance dose regimens in patients with DM is unknown.

METHODS AND RESULTS

In this randomized, cross-over study, patients with DM on treatment with dual antiplatelet therapy (aspirin and clopidogrel) were stratified according to CKD status and randomized to ticagrelor 90 mg bid or 60 mg bid. PK/PD assessments were performed at baseline, after 7-10 days of ticagrelor (peak and trough), and after 7-10 days of alternative ticagrelor regimen (peak and trough). PK assessments included plasma concentrations of ticagrelor and its major metabolite. PD assessments included VASP-PRI, VerifyNow P2Y12, and LTA.A total of 92 patients with DM (CKD, n = 44; non-CKD, n = 48) were randomized. Levels of platelet reactivity were lower with the 90 mg compared with the 60 mg ticagrelor dose, which was statistically significant in non-CKD but not in CKD patients for most PD measures. There were no significant differences in the primary endpoint (trough levels of VASP-PRI following ticagrelor 90 mg dosing) between cohorts (31 ± 20 vs 25 ± 14; p = 0.105). VerifyNow and LTA provided similar findings. PK assessments tracked PD profiles showing increased plasma concentrations of ticagrelor and its major metabolite in CKD compared to non-CKD patients.

CONCLUSION

In patients with DM, although ticagrelor maintenance dose regimens (60 mg and 90 mg) yield potent P2Y12 inhibition, levels of platelet reactivity tended to be higher and subject to broader variability in non-CKD compared with CKD patients.

CLINICAL TRIAL REGISTRATION

http://www.clinicaltrials.gov Unique Identifier: NCT02539160.

Use of the VerifyNow point of care assay to assess the pharmacodynamic effects of loading and maintenance dose regimens of prasugrel and ticagrelor

Prasugrel and ticagrelor are potent oral platelet P2Y₁₂ inhibitors and are recommended over clopidogrel in patients with acute coronary syndrome (ACS). Oral platelet P2Y₁₂ inhibitors are characterized by varying degrees of pharmacodynamic response profiles as assessed by a variety of commercially available assays. Because of its ease of use, rapid turnaround times and ability to provide results specific to P2Y₁₂ inhibitory effects, VerifyNow has emerged as one of the most commonly utilized platelet function assays. However, reference ranges with VerifyNow have been reported mainly for clopidogrel and there has not yet been any study specifically conducted to provide the expected on treatment reference ranges following administration of prasugrel and ticagrelor. This was a prospective single center investigation conducted in 120 patients with ACS who were treated with prasugrel or ticagrelor as per standard of care. Patients who underwent percutaneous coronary interventions (PCI) were treated with a loading dose of prasugrel (60 mg) or ticagrelor (180 mg), and patients who were on maintenance therapy were taking prasugrel (10 mg qd or 5 mg qd) or ticagrelor (90 mg bid). Platelet function testing was performed using the VerifyNow™ PRUTest™. The overall range of PRUTest values was lower than that observed in studies of patients treated with clopidogrel. The use of a maintenance dose regimen had a wider range of PRUTest values compared to the use of a loading dose for both prasugrel (1–179 vs. 2–128) and ticagrelor (1–196 vs. 1–177). The average PRUTest values in patients on prasugrel and ticagrelor maintenance dosing were 20% and 9% higher those observed in patients treated with a loading dose. PRUTest results following loading dose administration were very similar between drugs, but were 20% higher with prasugrel compared with ticagrelor during maintenance dosing. This study establishes expected PRUTest ranges for patients taking loading and maintenance doses of prasugrel and ticagrelor.

Clinical Trial Registrationhttp://www.clinicaltrials.gov Unique Identifier: NCT04492423, registered July 2020 retrospectively registered.

Effects of D-allulose on glucose tolerance and insulin response to a standard oral sucrose load: results of a prospective, randomized, crossover study

INTRODUCTION

Current dietary guidelines recommend limiting sugar intake for the prevention of diabetes mellitus (DM). Reduction in sugar intake may require sugar substitutes. Among these, D-allulose is a non-calorie rare monosaccharide with 70% sweetness of sucrose, which has shown anti-DM effects in Asian populations. However, there is limited data on the effects of D-allulose in other populations, including Westerners.

RESEARCH DESIGN AND METHODS

This was a prospective, randomized, double-blind, placebo-controlled, crossover study conducted in 30 subjects without DM. Study participants were given a standard oral (50 g) sucrose load and randomized to placebo or escalating doses of D-allulose (2.5, 5.0, 7.5, 10.0 g). Subjects crossed-over to the alternate study treatment after 7-14 days of wash out. Plasma glucose and insulin levels were measured at five time points: before and at 30, 60, 90 and 120 min after ingestion.

RESULTS

D-allulose was associated with a dose-dependent reduction of plasma glucose at 30 min compared with placebo. In particular, glucose was significantly lower with the 7.5 g (mean difference: 11; 95% CI 3 to 19; p=0.005) and 10 g (mean difference: 12; 95% CI 4 to 20; p=0.002) doses. Although glucose was not reduced at the other time points, there was a dose-dependent reduction in glucose excursion compared with placebo, which was significant with the 10 g dose (p=0.023). Accordingly, at 30 min D-allulose was associated with a trend towards lower insulin levels compared with placebo, which was significant with the 10 g dose (mean difference: 14; 95% CI 4 to 25; p=0.006). D-allulose did not reduce insulin at any other time point, but there was a significant dose-dependent reduction in insulin excursion compared with placebo (p=0.028), which was significant with the 10 g dose (p=0.002).

CONCLUSIONS

This is the largest study assessing the effects of D-allulose in Westerners demonstrating an early dose-dependent reduction in plasma glucose and insulin levels as well as decreased postprandial glucose and insulin excursion in subjects without DM. These pilot observations set the basis for large-scale investigations to support the anti-DM effects of D-allulose.

TRIAL REGISTRATION NUMBER

NCT02714413.

Prasugrel Versus Ticagrelor in Patients With CYP2C19 Loss-of-Function Genotypes: Results of a Randomized Pharmacodynamic Study in a Feasibility Investigation of Rapid Genetic Testing

The feasibility of rapid genetic testing in patients undergoing percutaneous coronary intervention (PCI) and the comparison of the pharmacodynamic effects of prasugrel versus ticagrelor among carriers of cytochrome P450 2C19 loss-of-function alleles treated with PCI has been poorly explored. Rapid genetic testing using the Spartan assay was shown to be feasible and provides results in a timely fashion in a real-world setting of patients undergoing coronary angiography (n = 781). Among patients (n = 223, 28.5%), carriers of at least 1 loss-of-function allele treated with PCI (n = 65), prasugrel, and ticagrelor achieve similar levels of platelet inhibition. (A Pharmacodynamic Study Comparing Prasugrel Versus Ticagrelor in Patients Undergoing PCI With CYP2C19 Loss-of-function [NCT02065479]).

Pharmacodynamic Effects of Vorapaxar in Prior Myocardial Infarction Patients Treated With Potent Oral P2Y12 Receptor Inhibitors With and Without Aspirin: Results of the VORA-PRATIC Study

Background Vorapaxar as an adjunct to dual antiplatelet therapy (DAPT) reduces thrombotic events in patients with prior myocardial infarction at the expense of increased bleeding. Withdrawal of aspirin has emerged as a bleeding reduction strategy. The pharmacodynamic effects of vorapaxar with potent P2Y12 inhibitors as well as the impact of dropping aspirin is unexplored and represented the aim of the VORA-PRATIC (Vorapaxar Therapy in Patients With Prior Myocardial Infarction Treated With Newer Generation P2Y12 Receptor Inhibitors Prasugrel and Ticagrelor) study. Methods and Results Post-myocardial infarction patients (n=130) on standard DAPT (aspirin+prasugrel or ticagrelor) were randomized to 1 of 3 arms: (1) triple therapy: aspirin+prasugrel/ticagrelor+vorapaxar; (2) dual therapy (drop aspirin): prasugrel/ticagrelor+vorapaxar; (3) DAPT: aspirin+prasugrel/ticagrelor. Pharmacodynamic assessments were performed at 3 time points (baseline and 7 and 30 days). Vorapaxar reduced CAT (collagen-ADP-TRAP)-induced platelet aggregation, a marker of platelet-mediated global thrombogenicity (triple therapy versus DAPT at 30 days: mean difference=-27; 95% CI,-35 to -19; P<0.001; primary end point). This effect was attenuated but still significant in the absence of aspirin (dual therapy versus DAPT at 30 days: mean difference=-15; 95% CI,-23 to -7; P<0.001; between-group comparisons, P<0.05). Vorapaxar abolished TRAP-induced aggregation (P<0.001), without affecting thrombin generation and clot strength. There were no differences in markers of P2Y12 reactivity. Markers sensitive to aspirin-induced effects increased (P<0.001) in the dual-therapy arm. Conclusions In post-myocardial infarction patients treated with potent P2Y12 inhibitors, vorapaxar reduces platelet-driven global thrombogenicity, an effect that persisted, albeit attenuated, in the absence of aspirin and without affecting markers of P2Y12 reactivity or clot kinetics. The clinical implications of these PD observations warrant future investigation. Registration URL: https://www.clini​caltr​ials.gov. Unique identifier: NCT02545933.

Platelet Inhibition With Cangrelor and Crushed Ticagrelor in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

BACKGROUND

The platelet inhibitory effects induced by oral P2Y₁₂ receptor antagonists are delayed in patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention (P-PCI). In turn, this leads to a gap in platelet inhibition, exposing patients to an increased risk of early thrombotic complications and underscoring the need to define strategies associated with more effective platelet inhibition in the peri-primary percutaneous coronary intervention period. Cangrelor is an intravenous P2Y₁₂ inhibitor with prompt and potent antiplatelet effects. However, to date, there are limited data on the effects of cangrelor used in combination with ticagrelor in patients undergoing primary percutaneous coronary intervention. Moreover, questions have emerged on the potential for drug-drug interactions during the transition from cangrelor to oral P2Y₁₂ inhibitors.

METHODS

This was a prospective, randomized, double-blind, placebo-controlled pharmacodynamic study conducted in patients undergoing primary percutaneous coronary intervention (n=50) who were randomized to treatment with either cangrelor or matching placebo (bolus followed by 2-hour infusion). All patients received ticagrelor 180-mg loading dose administered as crushed tablets at the time of cangrelor/placebo bolus administration. Pharmacodynamic analyses were performed at 8 time points. Pharmacodynamic effects were measured as P2Y₁₂ reaction units by VerifyNow and platelet reactivity index by vasodilator-stimulated phosphoprotein.

RESULTS

Compared with placebo, cangrelor was associated with reduced P2Y₁₂ reaction units as early as 5 minutes after bolus, which persisted during the entire duration of drug infusion, including at 30 minutes (63 [32-93] versus 214 [183-245]; mean difference, 152 [95% CI, 108-195]; P<0·001; primary end point). Parallel findings were shown with platelet reactivity index. Accordingly, high on-treatment platelet reactivity rates were reduced with cangrelor. After discontinuation of cangrelor/placebo infusion, there were no differences in levels of platelet reactivity between groups, ruling out a drug-drug interaction when cangrelor and ticagrelor are concomitantly administered.

CONCLUSIONS

In patients undergoing primary percutaneous coronary intervention, cangrelor is an effective strategy to bridge the gap in platelet inhibition associated with the use of oral P2Y₁₂ inhibition induced by ticagrelor. Ticagrelor can be administered as a crushed formulation concomitantly with cangrelor without any apparent drug-drug interaction. The clinical implications of these pharmacodynamic findings warrant investigation in an adequately powered clinical trial.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT03247738.

Effects of Edoxaban on the Cellular and Protein Phase of Coagulation in Patients with Coronary Artery Disease on Dual Antiplatelet Therapy with Aspirin and Clopidogrel: Results of the EDOX-APT Study

In patients requiring dual antiplatelet therapy (DAPT) who also have an indication to be treated with oral anticoagulant (OAC) drugs, aspirin withdrawal reduces the risk of bleeding. There is limited data on the pharmacodynamic effects associated with adding a nonvitamin K antagonist OAC on a background of aspirin and a P2Y12 inhibitor as well as dropping aspirin. Seventy-five patients on DAPT (aspirin plus clopidogrel) were randomized to DAPT plus high-dose edoxaban (60 mg once daily, Group A), DAPT plus low-dose edoxaban (30 mg once daily, Group B), or DAPT only (Group C) for 10 ± 2 days (Phase I). Afterwards, Groups A and B interrupted aspirin and maintained clopidogrel plus edoxaban for 10 ± 2 days, while patients in Group C maintained DAPT (Phase II). Platelet aggregation and clot kinetics were assessed at baseline, end of Phase I, and end of Phase II using thrombelastography (TEG), light transmittance aggregometry (LTA), VerifyNow P2Y12, and serum thromboxane-B2. The primary endpoint was the comparison of maximum amplitude (MA) measured by TEG, a measure of clot strength, between patients on DAPT plus high-dose edoxaban and patients on DAPT only. Edoxaban prolonged in a dose-dependent manner speed of thrombin generation (TEG R; Group A: 7.7 [6.8–8.7] vs. Group B: 7.4 [6.4–8.5] vs. Group C: 6.3 [5.7–7.0]; p = 0.05) but did not affect other markers of clot kinetics, including TEG MA (Group A: 63 [61–64] vs. Group B: 65 [63–67] vs. Group C: 64 [63–65]; p = 0.10). After aspirin discontinuation, platelet reactivity assessed by LTA using thrombin receptor activating peptide as agonist increased to a greater extent with low-dose edoxaban. Stopping aspirin did not affect markers of P2Y12 reactivity and had no or marginal effects on clot kinetics, but increased markers sensitive to cyclooxygenase-1 blockade.

Effects of Methylnaltrexone on Ticagrelor-Induced Antiplatelet Effects in Coronary Artery Disease Patients Treated With Morphine

OBJECTIVES

The aim of this study was to assess if intravenous methylnaltrexone can counteract the effects of morphine on the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of ticagrelor.

BACKGROUND

Morphine delays the onset of action of oral P2Y₁₂ receptor inhibitors, including ticagrelor, by inhibiting gastric emptying and leading to delayed drug absorption. Methylnaltrexone is a peripheral opioid receptor antagonist that has the potential to prevent opioid-induced peripherally mediated side effects (e.g., gastric emptying inhibition) without affecting analgesia.

METHODS

In this prospective, randomized, double-blind, placebo-controlled, crossover study, aspirin-treated patients with stable coronary artery disease (n = 30) were randomized to receive methylnaltrexone (0.3 mg/kg intravenous) or matching placebo. After methylnaltrexone or placebo administration, all patients received morphine (5 mg intravenous). This was followed 15 min later by a 180-mg loading dose of ticagrelor. Patients crossed over to the alternative study treatment after 7 ± 2 days of washout. PK and PD assessments were performed at 12 time points (6 pre- and 6 post-crossover). PK analysis included measurement of plasma levels of ticagrelor and its major active metabolite (AR-C124910XX). PD assessments included VerifyNow P2Y₁₂, light transmittance aggregometry, and vasodilator-stimulated phosphoprotein.

RESULTS

Only marginal changes in plasma levels of ticagrelor (and its major active metabolite) were observed with ticagrelor: maximum plasma concentration and area under the plasma concentration versus time curve from time 0 to the last measurable concentration were 38% and 30% higher, respectively, in patients receiving methylnaltrexone compared with those receiving placebo, but no differences in time to maximum plasma concentration were observed. There were no differences in P2Y₁₂ reaction units by VerifyNow P2Y₁₂ between groups at each time point, including 2 h (the primary endpoint; p = 0.261). Similarly, there were no differences in PD markers assessed by light transmittance aggregometry and vasodilator-stimulated phosphoprotein.

CONCLUSIONS

In patients with coronary artery disease receiving morphine, intravenous administration of the peripheral opioid receptor antagonist methylnaltrexone leads to only marginal changes in plasma levels of ticagrelor and its major metabolite, without affecting levels of platelet reactivity. (Effect of Methylnaltrexone on the PK/PD Profiles of Ticagrelor in Patients Treated With Morphine; NCT02403830).

Clinical implementation of rapid CYP2C19 genotyping to guide antiplatelet therapy after percutaneous coronary intervention

BACKGROUND

The CYP2C19 nonfunctional genotype reduces clopidogrel effectiveness after percutaneous coronary intervention (PCI). Following clinical implementation of CYP2C19 genotyping at University Florida (UF) Health Shands Hospital in 2012, where genotype results are available approximately 3 days after PCI, testing was expanded to UF Health Jacksonville in 2016 utilizing a rapid genotyping approach. We describe metrics with this latter implementation.

METHODS

Patients at UF Health Jacksonville undergoing left heart catheterization with intent to undergo PCI were targeted for genotyping using the Spartan RX™ system. Testing metrics and provider acceptance of testing and response to genotype results were examined, as was antiplatelet therapy over the 6 months following genotyping.

RESULTS

In the first year, 931 patients, including 392/505 (78%) total patients undergoing PCI, were genotyped. The median genotype test turnaround time was 96 min. Genotype results were available for 388 (99%) PCI patients prior to discharge. Of 336 genotyped PCI patients alive at discharge and not enrolled in an antiplatelet therapy trial, 1/6 (17%) poor metabolizers (PMs, with two nonfunctional alleles), 38/93 (41%) intermediate metabolizers (IMs, with one nonfunctional allele), and 119/237 (50%) patients without a nonfunctional allele were prescribed clopidogrel (p = 0.110). Clopidogrel use was higher among non-ACS versus ACS patients (78.6% vs. 42.2%, p < 0.001). Six months later, among patients with follow-up data, clopidogrel was prescribed in 0/4 (0%) PMs, 33/65 (51%) IMs, and 115/182 (63%) patients without a nonfunctional allele (p = 0.008 across groups; p = 0.020 for PMs versus those without a nonfunctional allele).

CONCLUSION

These data demonstrate that rapid genotyping is clinically feasible at a high volume cardiac catheterization facility and allows informed chronic antiplatelet prescribing, with lower clopidogrel use in PMs at 6 months. Trial registration ClinicalTrials.gov Identifier: NCT02724319; registered March 31, 2016; https://www.clinicaltrials.gov/ct2/show/NCT02724319?term=angiolillo&rank=7.

Pharmacodynamic Comparison of Prasugrel Versus Ticagrelor in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease: The OPTIMUS (Optimizing Antiplatelet Therapy in Diabetes Mellitus)-4 Study

BACKGROUND

Patients with diabetes mellitus (DM) are at increased risk of atherothrombotic events, underscoring the importance of effective platelet inhibiting therapies. Prasugrel and ticagrelor reduce thrombotic complications to a greater extent than clopidogrel. Subgroup analyses of pivotal clinical trials testing prasugrel and ticagrelor versus clopidogrel showed DM patients to have benefits that were consistent with the overall trial populations, although the magnitude of the ischemic risk reduction appeared to be enhanced with prasugrel. Whether these findings may be attributed to differences in the pharmacodynamic profiles of these drugs in DM patients remains poorly explored and represented the aim of this study.

METHODS

In this prospective, randomized, double-blind, double-dummy, crossover pharmacodynamic study, aspirin-treated DM patients (n=50) with coronary artery disease were randomly assigned to receive prasugrel (60 mg loading dose [LD]/10 mg maintenance dose once daily) or ticagrelor (180 mg LD/90 mg maintenance dose twice daily) for 1 week. Pharmacodynamic assessments were conducted using 4 different assays, including VerifyNow P2Y12, vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate, which allowed us to explore ADP- and non-ADP-induced (arachidonic acid-, collagen-, thrombin receptor-activating, peptide-induced) platelet signaling pathways. The acute (baseline, 30 minutes, and 2 hours post-LD) and maintenance (1 week) effects of therapy were assessed. The primary end point of the study was the comparison of P2Y12 reaction units determined by VerifyNow P2Y12 at 1 week between prasugrel and ticagrelor.

RESULTS

ADP- and non-ADP-induced measures of platelet reactivity reduced significantly with both prasugrel and ticagrelor LD and maintenance dose. P2Y12 reaction units defined by VerifyNow were similar between prasugrel and ticagrelor at 30 minutes and 2 hours post-LD. At 1 week, P2Y12 reaction units were significantly lower with ticagrelor than with prasugrel (52 [32-72] versus 83 [63-103]; least-square means difference: -31; 95% confidence interval, -57 to -4; P=0.022; primary end point). Pharmacodynamic assessments measured by vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate were similar between prasugrel and ticagrelor at each time point, including at 1 week. Rates of high on-treatment platelet reactivity were similar between groups with all assays at all time points.

CONCLUSIONS

In DM patients with coronary artery disease, ticagrelor exerts similar or greater inhibition of ADP-induced platelet reactivity in comparison with prasugrel in the acute and chronic phases of treatment, whereas the inhibition of measures of non-ADP-induced platelet reactivity was not significantly different between the 2 agents.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01852214.

PPARG and ADIPOQ gene polymorphisms increase type 2 diabetes mellitus risk in Asian Indian Sikhs: Pro12Ala still remains as the strongest predictor

We have examined the association of 14 tagging single nucleotide polymorphisms (tagSNPs) in peroxisome proliferator activated receptor-gamma transcripts 1 and 2 (PPARG1 and 2) and 5 tagSNPs in adiponectin (ADIPOQ) genes for their effect on type 2 diabetes mellitus (T2D) risk in Asian Indian Sikhs. A total of 554 T2D cases and 527 normoglycemic controls were examined for association with T2D and other subphenotypes of T2D. With the exception of a strong association of PPARG2/Pro12Ala with T2D (odds ratio, 0.13; 95% confidence interval, 0.03-0.56; P = .0007), no other tagSNP in the PPARG locus revealed any significant association with T2D in this population. Similarly, none of the tagSNPs in the ADIPOQ gene was associated with T2D susceptibility in single-site analysis. However, haplotype analysis provided strong evidence of association of these loci with T2D. Three-site haplotype analysis in the PPARG locus using the 2 marginally associated SNPs (P/rs11715073 and P/rs3892175) in combination with Pro12 Ala (P/rs1801282) revealed a strong association of 1 "risk" (CGC) (P = .003, permutation P = .015) and 1 "protective" (CAC) (P = .001, permutation P = .005) haplotype associated with T2D. However, the major effect still appears to be driven by Pro12Ala, as the association of these haplotypes did not remain significant when analyzed conditional upon Pro12Ala (P = .262). In addition, 2-site haplotype analysis in the ADIPOQ locus using only 2 marginally associated SNPs (AD/rs182052 and AD/rs7649121) revealed a significant protective association of the GA haplotype with T2D (P = .009, permutation P = .026). Multiple linear regression analysis also revealed significant association of an ADIPOQ variant (AD/rs12495941) with total body weight (P = .010), waist (P = .024), and hip (P = .021), although these associations were not significant after adjusting for multiple testing. Our new findings strongly suggest that the genetic variation in PPARG and ADIPOQ loci could contribute to the risk for the development of T2D in Indian Sikhs. Identification of causal SNPs in these important biological and positional candidate genes would help determine the true physiologic significance of these loci in T2D and obesity.