Pharmacokinetic Profiles of Ticagrelor Orodispersible Tablets in Healthy Western and Japanese Subjects

Current and Future Roles of Glycoprotein IIb-IIIa Inhibitors in Primary Angioplasty for ST-Segment Elevation Myocardial Infarction

Acute myocardial infarction still represents the major cause of mortality in high-income countries. Therefore, considerable efforts have been focused on the treatment of myocardial infarctions in the acute and long-term phase, with special attention being paid to reperfusion strategies and adjunctive antithrombotic therapies. In fact, despite the successful mechanical recanalization of the epicardial conduit, a substantial percentage of patients still experience poor myocardial reperfusion or acute/subacute in-stent thrombosis. Due the delayed onset of action of currently available oral antiplatelet therapies, glycoprotein (GP) IIb-IIIa inhibitors could be expected to improve clinical outcomes, especially when administrated in the early phase of the infarction, due to the larger platelet composition of fresh thrombi, the dynamic nature of early thrombi, and the larger amount of viable myocardium existing in the early, as compared to a delayed, phase. Considerable evidence has accumulated regarding the benefits from GP IIb-IIIa inhibitors on mortality, especially among high-risk patients and when administered as an upstream strategy. Therefore, based on currently available data, GP IIb-IIIa inhibitors can be considered when the drug can be administered within the first 3 h of symptom onset and among high-risk patients (e.g., those with advanced Killip class or an anterior myocardial infarction). Even though it is not universally accepted, in our opinion, this strategy should be implemented in a pre-hospital setting (in an ambulance) or as soon as possible when arriving at the hospital (at the Emergency Room or Coronary Care Unit, irrespective of whether they are in spoke or hub hospitals). A new, second-generation GP IIb-IIIa inhibitor (zalunfiban) appears to be highly suitable as a pre-hospital pharmacological facilitation strategy at the time of first medical contact due to its favourable features, including its simple subcutaneous administration, rapid onset of action (15 min), and limited time of action (with a half-life of ~1 h), which is likely to minimize the risk of bleeding. The ongoing CELEBRATE trial, including 2499 STEMI patients, may potentially provide compelling data to support the upstream treatment of STEMI patients undergoing mechanical reperfusion. In fact, although the current therapeutic target of increased rates of timely reperfusion has been achieved, the future goal in myocardial infarction treatment should be to achieve the most rapid reperfusion prior to primary percutaneous coronary intervention, thus further minimizing myocardial damage, or, in some cases, even preventing it completely, and improving survival.

Platelet inhibition with orodispersible ticagrelor in acute coronary syndromes according to morphine use: the TASTER study final results

AIM

To date, it is still unknown whether orodispersible tablet (ODT) ticagrelor might represent a suitable way to reach a proper antiaggregation in acute coronary syndrome (ACS) patients receiving morphine. Aim of the present study was to evaluate platelet inhibition with 180 mg ticagrelor loading dose (LD) administered as ODT compared with standard coated tablet ticagrelor formulation in ACS patients undergoing percutaneous coronary intervention (PCI) according to morphine use.

METHODS AND RESULTS

One-hundred and 30 patients presenting with STEMI or very high-risk NSTE-ACS were randomly assigned to receive ODT or standard ticagrelor LD. Potential morphine-ticagrelor interaction was assessed by stratified randomization according to morphine use. Platelet reactivity was evaluated by Platelet Reactivity Units (PRU) VerifyNow™ 1, 2, 4, and 6 h after ticagrelor LD. The primary endpoint was residual platelet reactivity 1 h after LD across the two ticagrelor formulation and according to morphine use. Safety endpoints were major bleedings and other in-hospital ticagrelor administration-related adverse events. One hour after LD, PRU median value was higher in morphine-treated patients (N = 32) as compared with patients not receiving morphine (N = 98; PRU = 187 [70-217]) vs. 73 [7-187]; P = 0.012). In patients with morphine, 1-h PRU values were similar between study groups (192 [114-236] vs. 173 [16-215] in ODT and standard tablet ticagrelor, respectively). Similarly, in patients without morphine, 1-h PRU values were not significantly different between study groups (69 [8-152] vs. 110 [6-193] in ODT and standard tablet ticagrelor, respectively). Platelet reactivity appeared similar in the 2 study arms at 2, 4, and 6 h after LD. No significant difference was observed among patients with or without morphine regarding in-hospital adverse events or drug side-effects, even if a reinfarction due to acute stent thrombosis was observed in a patient treated with morphine.

CONCLUSIONS

There was no difference between ODT and standard ticagrelor tablets in terms of post-LD residual platelet reactivity, percentage of platelet inhibition or safety regardless to morphine use.

Synthesis and evaluation of chitosan based controlled release nanoparticles for the delivery of ticagrelor

The aim of this contemporary work was to formulate a controlled release mucoadhesive nanoparticle formulation for enhancing the oral bioavailability of Ticagrelor (TG), a BCS class IV drug, having low oral bioavailability of about 36%. The nanoparticles can act as efficient carriers for hydrophobic drugs, due to having high surface area and hence can improve their aqueous solubility due to their hydrophilic nature. The nanoparticles (NPs) of TG were formulated using chitosan (CH) as polymer and sodium tripolyphosphate (TPP) as cross-linker, by ionic gelation technique with varying concentrations of polymer with respect to TG and TPP. Characterization of prepared nanoparticles was carried out to assess zeta potential, size, shape, entrapment efficiency (EE) and loading capacity (LC), using zeta sizer, surface morphology and chemical compatibility analysis. Drug release was observed using UV-Spectrophotometer. By increasing concentration of CH the desired size of particles (106.9 nm), zeta potential (22.6 mv) and poly dispersity index (0.364) was achieved. In vitro profiles showed a controlled and prolonged release of TG in both lower pH-1.2 and neutral pH-7.4 mediums, with effective protection of entrapped TG in simulated gastric conditions. X-ray diffraction patterns (XRD) showed the crystalline nature of formed NPs. Hence, this effort showed that hydrophobic drugs can be effectively encapsulated in nanoparticulate systems to enhance their solubility and stability, ultimately improving their bioavailability and effectiveness with better patient compliance by reducing dosing frequencies as well.

Effects of lignocaine vs. opioids on antiplatelet activity of ticagrelor: the LOCAL trial

AIMS

We assessed the impact of intravenous fentanyl and lignocaine on the pharmacokinetics and pharmacodynamics of ticagrelor in patients with unstable angina and non-ST-elevation myocardial infarction and their procedural analgesic efficacy and safety.

METHODS AND RESULTS

Seventy patients undergoing coronary angiography with ticagrelor loading were included in the pharmacokinetic and pharmacodynamic analyses of this randomized trial. Plasma ticagrelor levels 2 h post-loading dose were significantly lower in the fentanyl arm than in the lignocaine treatment arm (598 vs. 1008 ng/mL, P = 0.014). The area under the plasma-time curves for ticagrelor (1228 vs. 2753 ng h/mL, P < 0.001) and its active metabolite (201 vs. 447 ng h/mL, P = 0.001) were both significantly lower in the fentanyl arm. Expression of activated platelet glycoprotein IIb/IIIa receptor (2829 vs. 1426 mean fluorescence intensity, P = 0.006) and P-selectin (439 vs. 211 mean fluorescence intensity, P = 0.001) was significantly higher at 60 min in the fentanyl arm. A higher proportion of patients had high on-treatment platelet reactivity in the fentanyl arm at 60 min using the Multiplate Analyzer (41% vs. 9%, P = 0.002) and 120 min using the VerifyNow (30% vs. 3%, P = 0.003) and VASP (37% vs. 6%, P = 0.002) assays. Both drugs were well tolerated with a high level of patient satisfaction.

CONCLUSIONS

Unlike fentanyl, lignocaine does not impair the bioavailability or delay the antiplatelet effect of ticagrelor. Both drugs were well tolerated and effective with a high level of patient satisfaction for procedural analgesia. Routine procedural analgesia during percutaneous coronary intervention should be reconsidered and if performed, lignocaine is a beneficial alternative to fentanyl.

Blunting periprocedural myocardial necrosis: Rationale and design of the randomized ALPHEUS study

BACKGROUND

Clopidogrel associated with aspirin is the recommended treatment for patients undergoing elective percutaneous coronary intervention (PCI). Although severe PCI-related events are rare, evidence suggests that PCI-related myocardial infarction and myocardial injury are frequent complications that can impact the clinical prognosis of the patients. Antiplatelet therapy with a potent P2Y12 receptor inhibitor such as ticagrelor may reduce periprocedural ischemic complications while maintaining a similar safety profile as compared with conventional dual antiplatelet therapy by aspirin and clopidogrel in this setting.

METHODS

Assessment of Loading with the P2Y12 inhibitor ticagrelor or clopidogrel to Halt ischemic Events in patients Undergoing elective coronary Stenting (ALPHEUS) (NCT02617290) is an international, multicenter, randomized, parallel-group, open-label study in patients with stable coronary artery disease who are planned for an elective PCI. In total, 1,900 patients will be randomized before a planned PCI to a loading dose of ticagrelor 180 mg or a loading dose of clopidogrel (300 or 600 mg) in addition to aspirin. Patients will then receive a dual antiplatelet therapy with aspirin and ticagrelor 90 mg twice daily or clopidogrel 75 mg once daily for 30 days. The primary ischemic end point is PCI-related myocardial infarction (myocardial infarction type 4a or 4b) or major myocardial injury within 48 hours (or at hospital discharge if earlier) after elective PCI/stent. Safety will be evaluated by major bleeding events (Bleeding Academic Research Consortium type 3 or 5) at 48 hours (or discharge if it occurs earlier).

CONCLUSION

ALPHEUS is the first properly sized trial comparing ticagrelor to clopidogrel in the setting of elective PCI and is especially designed to show a reduction in periprocedural events, a surrogate end point for mortality.

A physiologically-based drug absorption modeling for orally disintegrating tablets

The aim of this research was to simulate oral pharmacokinetic (PK) profiles of atorvastatin from orally disintegrating tablets (ODTs) dosed without water ingestion in fasted humans. The in vitro dissolution profiles of three different formulations of ODTs were evaluated with fasted state biorelevant media using a paddle dissolution apparatus, and the results were coupled with an in silico model to simulate the in vivo oral PK profiles of ODTs following administration to humans. Since the dissolution rates of the ODTs in the intestinal medium (FaSSIF-V2) were highly affected by pre-exposure of the tablets to the stomach medium (FaSSGF), the simulation model took account of the relationship between the gastric emptying time and the dissolution performance of the tablets in the small intestine. The ODTs were formulated with drug-containing pellets. After oral dosing of the ODTs without water ingestion, gastric emptying of the pellets was assumed to follow first order kinetics. Thus, rate constants ranging between 0.69 and 8.3 h^-1 were applied in the PK simulations. The simulation model was built using Stella Professional® software. The results of the PK simulations suggest that the plasma concentration profiles of the ODTs can be described using the prediction model, but that different gastric emptying parameters for each ODT formulation are needed in humans.

Evaluation of cytochrome P450 3A4‑mediated drug‑drug interaction potential between P2Y12 inhibitors and statins

Ticagrelor and prasugrel are widely used in the treatment of acute coronary syndrome. The co‑administration of ticagrelor or prasugrel with statins in the clinic has already drawn a great deal of attention. The aims of the present study were to evaluate the safety and effectiveness, and guide the rational clinical use of, co‑administration of ticagrelor or prasugrel with statins by exploring potential drug interactions. The activity of cytochrome P450 family 3 subfamily A member 4 (CYP3A4) was detected, and its protein and mRNA expression levels were measured in a rat model and liver microsomes to evaluate the effect of the drug combinations on CYP3A4. High performance liquid chromatography, western blotting and reverse transcription‑quantitative PCR were used to perform these investigations. The in vitro experiments suggested that ticagrelor inhibited CYP3A4 activity, with IC50 and inhibitor constant (Ki) values of 68.74 and 26.47 µM, respectively; prasugrel also inhibited CYP3A4, activity with IC50 and Ki values of 16.24 and 10.84 µM, respectively. When different dosages of the antagonists were combined with simvastatin or atorvastatin, the metabolic rate was reduced more effectively at higher dosages when compared with lower dosages. An in vivo pharmacokinetic study demonstrated that the co‑administration of ticagrelor or prasugrel with simvastatin caused an increase in the principal pharmacokinetic parameters of the probe drug dapsone [area under the concentration/time curve (AUC)0‑t, AUC0‑∞ and t1/2] and a decrease in clearance compared with ticagrelor, prasugrel or simvastatin alone. Additional studies confirmed that the two investigated P2Y12 inhibitors were able to decrease the protein level of CYP3A4 by promoting protein degradation through the proteasomal pathway, and combination with statins such as simvastatin had a synergistic inhibitory effect on CYP3A4 activity. These results demonstrated that the co‑administration of P2Y12 inhibitors with simvastatin could markedly inhibit the activity of CYP3A4, and these findings will further influence the assessment of the clinical effectiveness (reduced or enhanced efficacy) and safety (bleeding and rhabdomyolysis) in the clinic.

Efficacy and safety of alternative oral administrations of P2Y12-receptor inhibitors: Systematic review and meta-analysis

BACKGROUND

Early administration of P2Y12-receptor inhibitors is recommended in all patients with acute coronary syndrome undergoing invasive management, with the aim to achieve the fastest and most effective platelet inhibition. Several trials investigated alternative methods of P2Y12-receptor inhibitor administration (mainly chewed or crushed) aimed at ensuring faster and higher platelet inhibition. Thus, we decided to perform a systematic review and meta-analysis analyzing efficacy and safety of alternative P2Y12-receptor inhibitor administration strategies.

METHODS

Systematic research was performed on Pubmed, Cochrane Library, Biomed Central, and Web of Science databases. We included randomized or observational trials testing at least one P2Y12-receptor inhibitor alternative administration. The primary outcome of the study was the value of the platelet reactivity unit (PRU) at 1 h after drug administration, assessed by VerifyNow P2Y12 test (Accumetrics, Inc., San Diego, CA). Secondary outcomes were adverse bleeding events (safety outcome).

RESULTS AND DISCUSSION

Fourteen studies were selected for qualitative analysis. Five studies, all focused on ticagrelor, were selected for quantitative efficacy analyses. These five studies compared the administration of crushed/chewed ticagrelor 180 mg loading dose (LD) with the standard whole tablets LD. The pooled mean difference between the two administrations was -59.24 PRU (95% CI from -30.61 to -87.87 PRU) in favor of the crushed/chewed administration, corresponding to a 25% mean relative PRU reduction between alternative and standard P2Y12-receptor inhibitor administrations at 1 h after drug intake. A similar relationship was found in other studies on alternative administration of clopidogrel and prasugrel, not included in the quantitative analysis.