Małgorzata Ostrowska

Morphine delays and attenuates ticagrelor exposure and action in patients with myocardial infarction: the randomized, double-blind, placebo-controlled IMPRESSION trial

Abstract Aims The currently available data indicate a drug–drug interaction between morphine and oral P2Y12 receptor inhibitors, when administered together. The aim of this trial was to assess the influence of infused morphine on pharmacokinetics and pharmacodynamics of ticagrelor and its active metabolite (AR-C124910XX) in patients with acute myocardial infarction. Methods and results In a single-centre, randomized, double-blind trial, patients were assigned in a 1:1 ratio to receive intravenously either morphine (5 mg) or placebo, followed by a 180 mg loading dose of ticagrelor. Pharmacokinetics was determined with liquid chromatography tandem mass spectrometry and ticagrelor antiplatelet effects were measured with up to three different platelet function tests: vasodilator-stimulated phosphoprotein phosphorylation assay, multiple electrode aggregometry and VerifyNow. The pharmacokinetic and pharmacodynamic assessment was performed in 70 patients (35 in each study group). Morphine lowered the total exposure to ticagrelor and its active metabolite by 36% (AUC(0–12): 6307 vs. 9791 ng h/mL; P = 0.003), and 37% (AUC(0–12): 1503 vs. 2388 ng h/mL; P = 0.008), respectively, with a concomitant delay in maximal plasma concentration of ticagrelor (4 vs. 2 h; P = 0.004). Multiple regression analysis showed that lower AUC(0–12) values for ticagrelor were independently associated with the administration of morphine (P = 0.004) and the presence of ST-segment elevation myocardial infarction (P = 0.014). All three methods of platelet reactivity assessment showed a stronger antiplatelet effect in the placebo group and a greater prevalence of high platelet reactivity in patients receiving morphine. Conclusions Morphine delays and attenuates ticagrelor exposure and action in patients with myocardial infarction. ClinicalTrials.gov Identifier: NCT02217878.

Overview of pleiotropic effects of platelet P2Y12 receptor inhibitors.

Dual antiplatelet therapy consisting of one of the P2Y12 receptor inhibitors in conjunction with aspirin is the mainstay of treatment for patients with acute coronary syndromes (ACS) and those undergoing percutaneous coronary interventions (PCI). In recent years, multiple extra-platelet features of P2Y12 receptor antagonists have been reported in numerous clinical trials. The aim of this review is to summarise reported pleiotropic effects of clopidogrel, prasugrel, ticagrelor and other P2Y12 receptor blockers. We included observations made both in human and in animal models, together with proposed mechanisms of action for described features. If confirmed in randomised studies and properly applied to everyday practice, the observed extra-platelet actions could enable us to improve efficacy of ACS and post-PCI treatment, as well as to confine mortality and occurrence rate of cardiovascular events.

New directions for pharmacotherapy in the treatment of acute coronary syndrome

ABSTRACT Introduction: Acute coronary syndromes (ACS) are one of the leading causes of death worldwide. Several landmark trials, followed by a widespread introduction of new agents, have significantly improved ACS outcomes in recent years. However, despite the use of contemporary therapy, a substantial number of ACS patients continue to suffer from cardiovascular events. Areas covered: The aim of this review was to summarize available data on innovative drugs and pharmacological strategies that have potential to amend the current ACS therapy. We present the results of recent large clinical trials, as well as insights from ongoing phase III and phase IV studies, exploring the value of new strategies for the improvement of outcomes in ACS. Expert opinion: More potent platelet inhibition, more profound lipid reduction and possibly anti-inflammatory action are considered to have potential to further reduce the rates of adverse cardiovascular and thrombotic events in ACS patients. ‘Hit fast, hit hard’ approach regarding novel antiplatelet and lipid-lowering therapy seems attractive, but it has to be considered that these strategies may be associated with increased adverse events rate. Introduction of cangrelor and ezetimibe, and potentially future recognition of proprotein convertase subtilisin/kexin type 9 antibodies, are likely to alter the landscape of ACS pharmacotherapy.

Comparison of Ticagrelor Pharmacokinetics and Pharmacodynamics in STEMI and NSTEMI Patients (PINPOINT): protocol for a prospective, observational, single-centre study

Introduction The most common classification of acute myocardial infarction (AMI) is based on electrocardiographic findings and distinguishes ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI). Both types of AMI differ concerning their epidemiology, clinical approach and early outcomes. Ticagrelor is a P2Y12 receptor inhibitor, constituting the first-line treatment for STEMI and NSTEMI. According to available data, STEMI may be associated with lower plasma concentration of ticagrelor in the first hours of AMI, but currently there are no studies directly comparing ticagrelor pharmacokinetics or antiplatelet effect in patients with STEMI versus NSTEMI. Methods and analysis The PINPOINT study is a phase IV, single-centre, investigator-initiated, prospective, observational study designed to compare the pharmacokinetics and pharmacodynamics of ticagrelor in patients with STEMI and NSTEMI assigned to the invasive strategy of treatment. Based on an internal pilot study, the trial is expected to include at least 23 patients with each AMI type. All subjects will receive a 180 mg loading dose of ticagrelor. The primary end point of the study is the area under the plasma concentration-time curve (AUC(0–6)) for ticagrelor during the first 6 hours after the loading dose. Secondary end points include various pharmacokinetic features of ticagrelor and its active metabolite (AR-C124910XX), and evaluation of platelet reactivity by the vasodilator-stimulated phosphoprotein assay and multiple electrode aggregometry. Blood samples for the pharmacokinetic and pharmacodynamic assessment will be obtained at pretreatment, 30 min, 1, 2, 3, 4, 6 and 12 hours post-ticagrelor loading dose. Ethics and dissemination The study received approval from the Local Ethics Committee (Komisja Bioetyczna Uniwersytetu Mikołaja Kopernika w Toruniu przy Collegium Medicum im. Ludwika Rydygiera w Bydgoszczy; approval reference number KB 617/2015). The study results will be disseminated through conference presentations and peer-reviewed journals. Trial registration number NCT02602444; Pre-results.

Which platelet function test best reflects the in vivo plasma concentrations of ticagrelor and its active metabolite

Aim of this study was assessment of the relationship between concentrations of ticagrelor and its active metabolite (AR-C124910XX) and results of selected platelet function tests. In a single-centre, cohort study, patients with myocardial infarction underwent blood sampling following a 180 mg ticagrelor loading dose intake (predose, 1, 2, 3, 4, 6, 12, 24 hours postdose) to perform pharmacokinetic and pharmacodynamic assessments. Platelet reactivity was evaluated using the VASP-assay, the VerifyNow device and the Multiplate analyzer. Analysis of 36 patients revealed high negative correlations between ticagrelor concentrations and platelet reactivity evaluated with all three platelet function tests (the VASP-assay: RS=-0.722; p<0.0001; the VerifyNow device: RS=-0.715; p<0.0001; the Multiplate analyzer: RS=-0.722; p<0.0001), with no significant differences between correlation coefficients. Similar results were found for AR-C124910XX. Platelet reactivity values assessed with all three methods generally correlated well with each other; however, a significantly higher correlation (p<0.02) was demonstrated between the VerifyNow and Multiplate tests (RS=0.707; p<0.0001) than in other assay combinations (the VASP-assay and the VerifyNow device: RS=0.595; p<0.0001; the VASP-assay and the Multiplate analyzer: RS=0.588; p<0.0001). With respect to the recognition of high platelet reactivity, we found higher measurement concordance between the VerifyNow and Multiplate tests compared with other assay combinations, while for low platelet reactivity, only results of the VerifyNow and Multiplate assay were related to each other. Platelet reactivity measurements performed with the VASP, VerifyNow and Multiplate tests show comparably strong negative correlations with ticagrelor and AR-C124910XX concentrations.

Comparison of bioavailability and antiplatelet action of ticagrelor in patients with ST-elevation myocardial infarction and non-ST-elevation myocardial infarction: A prospective, observational, single-centre study

Background Data from available studies suggest that the presence of ST-elevation myocardial infarction (STEMI) may be associated with delayed and attenuated ticagrelor bioavailability and effect compared with non-ST-elevation myocardial infarction (NSTEMI). Methods In a single-center, prospective, observational trial 73 patients with myocardial infarction (STEMI n = 49, NSTEMI n = 24) underwent a pharmacokinetic and pharmacodynamic assessment after a 180 mg ticagrelor loading dose (LD). Ticagrelor and its active metabolite (AR-C124910XX) plasma concentrations were determined with liquid chromatography tandem mass spectrometry, and their antiplatelet effect was measured with the VASP assay and multiple electrode aggregometry. Results During the first six hours after ticagrelor LD, STEMI patients had 38% and 34% lower plasma concentration of ticagrelor and AR-C124910XX, respectively, than NSTEMI (ticagrelor AUC(0–6): 2491 [344–5587] vs. 3991 [1406–9284] ng*h/mL; p = 0.038; AR-C124910XX AUC(0–6): 473 [0–924] vs. 712 [346–1616] ng*h/mL; p = 0.027). STEMI patients also required more time to achieve maximal concentration of ticagrelor (tmax: 4.0 [3.0–12.0] vs. 2.5 [2.0–6.0] h; p = 0.012). Impaired bioavailability of ticagrelor and AR-C124910XX seen in STEMI subjects was associated with diminished platelet inhibition in this group, which was most pronounced during the initial hours of treatment. Conclusions Plasma concentrations of ticagrelor and AR-C124910XX during the first hours after ticagrelor LD were one third lower in STEMI than in NSTEMI patients. This reduced and delayed ticagrelor bioavailability was associated with weaker antiplatelet effect in STEMI. Clinical trial registration ClinicalTrials.gov identifier: NCT02602444 (November 09, 2015)

Prediction of high risk of non-adherence to antiplatelet treatment

BACKGROUND Dual antiplatelet therapy with acetylsalicylic acid (ASA) and clopidogrel is the standard of care for secondary prevention. Premature discontinuation of clopidogrel is associated with an increased risk of myocardial infarction (MI) or death, and greater health care expenditure. AIM To develop an objective method for identification of patients with high risk of non-adherence to clopidogrel after MI. METHODS A total of 189 patients were enrolled into a prospective, observational, single-centre study with a nine-month follow-up. Patients received a 600-mg loading dose and 75-mg maintenance dose of clopidogrel in combination with ASA doses of 300 mg and 75 mg, respectively. Adenosine diposphate-induced platelet aggregation (ADP-PA) was assessed during baseline hospitalisation and at three, six, and nine months after discharge. Adherence to medication with clopidogrel was defined as the proportion of drug availability based on data from the National Health Fund regarding prescribed drug purchases. Adherence was arbitrarily judged adequate when the proportion exceeded 80%. RESULTS According to our hypothesis, ADP-PA in non-adherent patients should be higher at follow-up visits (at least once) as compared with measurement at hospitalisation. Based on the ROC curve analysis, the optimal cut-off point equal to 4 U was defined (p < 0.0001, 95% CI 0.562-0.654; sensitivity: 60.6%, specificity: 57.1%, positive predictive value: 63.3%, negative predictive value: 54.2%). The prevalence of true adherence to medication in groups of high and low probability of adherence defined according to developed criteria amounted 60 (50.8%) and 23 (32.4%) cases, respectively (p = 0.01). CONCLUSIONS The newly developed method of objective identification of patients with high risk of non-adherence to clopidogrel after MI is easily applicable and cheap, and, despite relatively low sensitivity and specificity, it efficiently differentiates patients with regard to clinical end-points during follow-up.

Does morphine administration affect ticagrelor conversion to its active metabolite in patients with acute myocardial infarction? A sub-analysis of the randomized, double-blind, placebo- -controlled IMPRESSION trial

Background. Therapy with aspirin and one of the platelet P2Y12 receptor inhibitors, preferably ticagrelor or prasugrel, is the mainstay of acute myocardial infarction (AMI) treatment. Morphine is the most commonly used analgesic in AMI patients. The IMPRESSION study was the first randomized trial to confirm that morphine use in this clinical setting leads to a delayed and attenuated exposure to ticagrelor and its active metabolite (AR-C124910XX). The mechanism underlying this drug-drug interaction remains hypothetical. Material and methods. A post hoc sub-analysis of the IMPRESSION study, a phase IV, single center, randomized, double-blind, placebo-controlled trial, was performed to examine whether morphine administration interferes with the proportion of AR-C124910XX produced from ticagrelor in AMI patients. Pharmacokinetic results of all subjects pretreated with placebo (n = 35) and morphine (n = 35) were analyzed. The ratio of total exposure to AR-C124910XX to total exposure to ticagrelor for 12 h was used to illustrate the rate of ticagrelor metabolism. Total exposure to investigated compounds was measured as the area under the plasma concentration-time curve (AUC). Results. The ratios of AUC(0–12) for AR-C124910XX to AUC(0–12) for ticagrelor were comparable between morphine and placebo pretreated patients (20.9 [13.9–34.6] v. 24.7 [18.1–29.6] %; p = 0.58). Importantly, visual inspection of the relationship between AUC(0–12) for AR-C124910XX and AUC(0–12) for ticagrelor revealed that regression lines for the morphine and placebo groups were located closely to each other, with a tendency for superimposing. Additionally, we observed similar values of slope coefficients for both study arms in the linear regression equations illustrating the relationship between AUC(0–12) for AR-C124910XX and AUC(0–12) for ticagrelor (0.19 [± 0.03] v. 0.21 [± 0.04]; p for the statistical significance of both slope coefficients < 0.0001). Conclusions. In the IMPRESSION study, conversion of ticagrelor to AR-C124910XX in AMI patients was not affected by morphine administration.

Basic laboratory parameters as predictors of in-hospital death in patients with acute decompensated heart failure: data from a large single-centre cohort

BACKGROUND Heart failure (HF) is a growing cause of hospitalisation worldwide, and despite significant progress in its treat-ment it is still associated with high mortality. AIM The aim of this study was to find factors predicting in-hospital death in acute decompensated HF by analysis of basic laboratory data and echocardiography, routinely collected on admission to the hospital. METHODS To this single-centre retrospective study we involved 638 consecutive patients hospitalised in the years 2007-2008 due to acute decompensated HF. To the initial univariate analysis we included the results of echocardiography and 36 basic laboratory tests performed at hospital admission. Parameters significantly associated with in-hospital death in univariate analysis were taken to multivariate regression analysis. RESULTS In-hospital death occurred in 119 cases (median age 75 years; 40.3% females). The multivariate analysis revealed sig-nificant association between in-hospital death and: higher leukocyte count (death [D]: 13.5 vs. survival [S]: 8.8 G/L, p < 0.01), higher neutrophil count (D: 10.5 vs. S: 5.9 G/L, p < 0.01), lower lymphocyte count (D: 1.3 vs. S: 1.7 G/L, p < 0.05), higher C-reactive protein concentration (D: 20.8 vs. S: 6.7 mg/dL, p < 0.01), higher serum glucose concentration (D: 167.0 vs. S: 116.0 mg/dL, p < 0.00001), higher serum creatinine concentration (D: 1.5 vs. S: 1.2 mg/dL, p < 0.0001), higher blood urea nitrogen concentration (D: 29.0 vs. S: 22.0 mg/dL, p < 0.00001), and higher aspartate aminotransferase (D: 72.0 vs. S: 27.0 U/L, p < 0.0001). Surprisingly, there was no significant association with echocardiographic parameters. CONCLUSIONS Analysis of basic laboratory data collected on admission to the hospital may help to identify patients with acute decompensated HF, who are at high risk of in-hospital death.

Off-target effects of glycoprotein IIb/IIIa receptor inhibitors.

Soon after identification of the platelet membrane glycoprotein (GP) IIb/IIIa, it has become a target of antiplatelet therapy. There are 3 intravenous GP IIb/IIIa receptor inhibitors, namely- eptifibatide, tirofiban and abciximab, used in the contemporary clinical practice, particularly in patients with acute coronary syndrome undergoing percutaneous coronary intervention (PCI). The aim of the current review is to summarize available knowledge concerning off-target effects of GP IIb/IIIa receptor inhibitors. All 3 drugs have similar antithrombotic properties, but differ with respect to pharmacodynamics, pharmacokinetics and off-target effects. Eptifibatide and tirofiban are highly specific GP IIb/IIIa receptor inhibitors, while abciximab is unselectiveand cross-reacts with integrin avb3 - a vitronectin receptor and leukocyte-associatedi ntegrin Mac-1. As a result of these interactions, abciximab seems to reduce the development of clinical restenosis, decrease infarct size, inhibit adhesion of monocytes to medical steel and modulate the inflammatory response. Intracoronary administration of abciximab provides higher drug concentration in the target area, increasing dose-dependent interactions with other integrins. Off-target effects of small molecule GP IIb/IIIa receptor inhibitors (i.e. eptifibatide and tirofiban) are predominantly connected with their suppressive influence on the inflammatory response. All in all, although GP IIb/IIIa receptor inhibitors are not recommended as a routine therapy during PCI, their antiplatelet properties and potential off-target effects may bebeneficial in certain subsets of patients.