Diurnal Variability of Platelet Aggregation in Patients with Myocardial Infarction Treated with Prasugrel and Ticagrelor.

Background: Contemporary antiplatelet treatment in acute myocardial infarction (AMI) is based on one of two P2Y12 receptor inhibitors, prasugrel or ticagrelor. The aim of this study was to compare diurnal variability of platelet reactivity between patients receiving prasugrel and ticagrelor during the initial phase of maintenance treatment after AMI.

Methods: It was a prospective, two-center, pharmacodynamic, observational study.

A new approach to ticagrelor-based de-escalation of antiplatelet therapy after acute coronary syndrome. A rationale for a randomized, double-blind, placebo-controlled, investigator-initiated, multicenter clinical study.

The risk of ischemic events gradually decreases after acute coronary syndrome (ACS), reaching a stable level after 1 month, while the risk of bleeding remains steady during the whole period of dual antiplatelet treatment (DAPT). Several de-escalation strategies of antiplatelet treatment aiming to enhance safety of DAPT without depriving it of its efficacy have been evaluated so far. We hypothesized that reduction of the ticagrelor maintenance dose 1 month after ACS and its continuation until 12 months after ACS may improve adherence to antiplatelet treatment due to better tolerability compared with the standard dose of ticagrelor.

Oral NAloxone to overcome the moRphine effect in acute COronary syndrome patients treated with TICagrelor - NARCOTIC trial.

Background: Numerous worldwide clinical trials have proven the indisputably negative influence of morphine on the pharmacokinetics and pharmacodynamics of P2Y12 receptor inhibitors in patients presenting with acute coronary syndromes. The aim of this trial was to evaluate whether oral coadministration of an anti-opioid agent, naloxone, can be considered a successful approach to overcome 'the morphine effect'.

Methods: Consecutive unstable angina patients receiving ticagrelor and morphine with or without orally administered naloxone underwent assessment of platelet reactivity using Multiplate analyzer as well as evaluation of the pharmacokinetic profile of ticagrelor and its active metabolite, AR-C124910XX, at 9 pre-defined time points within the first 6 hours following oral intake of the ticagrelor loading dose.

Determinants of high platelet reactivity in patients with acute coronary syndromes treated with ticagrelor.

High platelet reactivity (HPR) is a risk factor for stent thrombosis, a potentially lethal complication of percutaneous coronary intervention. HPR is also associated with increased risk of myocardial infarction and death in invasively-treated patients with acute coronary syndrome (ACS). HPR occurs even in ACS patients treated with ticagrelor, a state-of-the-art antiplatelet agent, especially during the first hours of treatment.

Platelet inhibition with standard vs. lower maintenance dose of ticagrelor early after myocardial infarction (ELECTRA): a randomized, open-label, active-controlled pharmacodynamic and pharmacokinetic study.

Aims: Currently available data indicate that reduction of ticagrelor maintenance dose (MD) 1-3 years after acute myocardial infarction (AMI) not only provides sufficient platelet inhibition but also can improve ticagrelor's safety profile. The aim of this study was to compare the antiplatelet effect of reduced and standard ticagrelor MD in stable patients beginning 1 month after AMI.

Methods And Results: In a single-centre, randomized, open-label, active-controlled trial, on Day 30 following AMI, 52 patients (26 in each study arm) were assigned in a 1:1 ratio to receive either reduced (60 mg b.

METoclopramide Administration as a Strategy to Overcome MORPHine-ticagrelOr Interaction in PatientS with Unstable Angina PectorIS-The METAMORPHOSIS Trial.

Extensive search for methods of overcoming morphine-related delay of the absorption and onset of action of oral P2Y inhibitors in patients presenting with acute coronary syndrome is on-going. The aim of the trial was to investigate whether metoclopramide co-administration could reduce this delay and improve the pharmacokinetics (PKs) and pharmacodynamics (PDs) of ticagrelor and its active metabolite AR-C124900XX. Plasma concentration of both compounds and platelet reactivity were evaluated in nine pre-defined time points within 6 hours after administration of ticagrelor loading dose.

Metabolism of ticagrelor in patients with acute coronary syndromes.

Ticagrelor is a state-of-the-art antiplatelet agent used for the treatment of patients with acute coronary syndromes (ACS). Unlike remaining oral P2Y12 receptor inhibitors ticagrelor does not require metabolic activation to exert its antiplatelet action. Still, ticagrelor is extensively metabolized by hepatic CYP3A enzymes, and AR-C124910XX is its only active metabolite.

Crushed sublingual versus oral ticagrelor administration strategies in patients with unstable angina. A pharmacokinetic/pharmacodynamic study.

Oral administration of crushed ticagrelor tablets turned out to be an efficacious method that improves its pharmacokinetics and pharmacodynamics. This strategy, however, is unlikely to eliminate the drug-drug interaction in patients receiving intravenous morphine, as the impairment of the P2Y12 inhibitor absorption related to decreased propulsive motility of the gastro-intestinal tract is the most likely mechanism of interaction. Thus, we designed a pharmacokinetic and pharmacodynamic study setting the feasibility of platelet inhibition with a loading dose of ticagrelor given as crushed tablets sublingually compared with two other ticagrelor loading dose administration strategies: integral tablet given orally and crushed tablet given orally in patients with unstable angina.