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

Evaluating the pharmacokinetic and pharmacodynamic impact of different modes of ticagrelor administration

INTRODUCTION

Alternative administration modes for oral P2Y12 inhibitors, particularly ticagrelor, have emerged as a potential alternative to overcome the limitations associated with the delayed onset of action of these drugs in patients who are unable to swallow or with impaired absorption.

AREAS COVERED

This comprehensive literature review aims to provide an overview of the current state of knowledge on the pharmacokinetics and administration modes of ticagrelor, including factors that may affect its action. It also compares the pharmacokinetics of ticagrelor with that of other drugs with similar uses to provide a comprehensive understanding of the potential advantages and limitations of different modalities of P2Y12 administration. For this purpose, Embase, Medline, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, Google Scholar, and ClinicalTrials.gov were searched from database inception to July 2023.

EXPERT OPINION

Among the different alternatives, crushed formulations, especially for ticagrelor, have emerged as the most promising option, showing early and robust platelet inhibition. However, important questions remain unanswered, such as the comparative clinical benefits of crushed ticagrelor versus standard administration, the cost-effectiveness of alternative modes compared to intravenous P2Y12 inhibitors such as cangrelor, and the important limitations associated with the concomitant use of opioids, who have been proven to impair even the action of crushed ticagrelor.

Randomized, Double-Blind, Active Comparator Pharmacodynamic Study of Platelet Inhibition with Crushed and Integral Formulations of Clopidogrel and Ticagrelor in Acute Coronary Syndrome

BACKGROUND

Crushed formulations of specific antiplatelet agents produce earlier and stronger platelet inhibition. We studied the platelet inhibitory effect of crushed clopidogrel in patients with acute coronary syndrome (ACS) and its relative efficacy compared with integral clopidogrel, crushed and integral ticagrelor.

OBJECTIVES

We aimed to compare the platelet inhibitory effect of crushed and integral formulations of clopidogrel and ticagrelor in patients with acute coronary syndrome (ACS).

METHODS

Overall, 142 patients with suspected ACS were randomly assigned to receive crushed or integral formulations of clopidogrel or ticagrelor. Platelet inhibition at baseline and 1 and 8 h was assessed using the VerifyNow assay. High on-treatment platelet reactivity (HTPR) ≥ 235 P2Y₁₂ reaction units (PRUs) 1 h after the medication loading dose was also determined.

RESULTS

The PRU and percentage inhibition median (interquartile range) at 1 h for the different formulations were as follows: crushed clopidogrel: 196.50 (155.50, 246.50), 9.36 (- 1.79, 25.10); integral clopidogrel: 189.50 (159.00, 214.00), 2.32 (- 2.67, 19.89); crushed ticagrelor: 59.00 (10.00, 96.00), 75.53 (49.12, 95.18); and integral ticagrelor: 126.50 (50.00, 168.00), 40.56 (25.59, 78.69). There was no significant difference in PRU or percentage platelet inhibition between the crushed and integral formulations of clopidogrel (p = 0.990, p = 0.479); both formulations of ticagrelor were superior to the clopidogrel formulations (p < 0.05). On paired comparison, crushed ticagrelor showed robust early inhibition of platelets compared with the integral formulation (p = 0.03). Crushed clopidogrel exhibited the maximal HTPR of 34.3%, but was < 3% for both formulations of ticagrelor.

CONCLUSIONS

The platelet inhibitory effect of crushed clopidogrel is not superior to integral preparation in patients with ACS. Crushed ticagrelor produced maximal platelet inhibition acutely. HTPR rates in ACS are similar and very low with both formulations of ticagrelor, and maximal with crushed clopidogrel. Clinical Trials Registry of India identifier number CTRI/2020/06/025647.

Dual Antiplatelet Therapy with Parenteral P2Y12 Inhibitors: Rationale, Evidence, and Future Directions

Dual antiplatelet therapy (DAPT), consisting of the combination of aspirin and an inhibitor of the platelet P2Y₁₂ receptor for ADP, remains among the most investigated treatments in cardiovascular medicine. While a substantial amount of research initially stemmed from the observations of late and very late stent thrombosis events in the first-generation drug-eluting stent (DES) era, DAPT has been recently transitioning from a purely stent-related to a more systemic secondary prevention strategy. Oral and parenteral platelet P2Y₁₂ inhibitors are currently available for clinical use. The latter have been shown to be extremely suitable in drug-naïve patients with acute coronary syndrome (ACS), mainly because oral P2Y₁₂ inhibitors are associated with delayed efficacy in patients with STEMI and because pre-treatment with P2Y₁₂ inhibitors is discouraged in NSTE-ACS, and in patients with recent DES implantation and in need of urgent cardiac and non-cardiac surgery. More definitive evidence is needed, however, about optimal switching strategies between parenteral and oral P2Y₁₂ inhibitors and about newer potent subcutaneous agents that are being developed for the pre-hospital setting.

Current and Future Insights for Optimizing Antithrombotic Therapy to Reduce the Burden of Cardiovascular Ischemic Events in Patients with Acute Coronary Syndrome

The pharmacological treatment strategies for acute coronary syndrome (ACS) in recent years are constantly evolving to develop more potent antithrombotic agents, as reflected by the introduction of more novel P2Y₁₂ receptor inhibitors and anticoagulants to reduce the ischemic risk among ACS patients. Despite the substantial improvements in the current antithrombotic regimen, a noticeable number of ACS patients continue to experience ischemic events. Providing effective ischemic risk reduction while balancing bleeding risk remains a clinical challenge. This updated review discusses the currently approved and widely used antithrombotic agents and explores newer antithrombotic treatment strategies under development for the initial phase of ACS.

Crushed/chewed administration of potent P2Y12 inhibitors in ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: Systematic review and meta-analysis

Crushed or chewed potent P2Y₁₂ inhibitors are commonly used in the hope of bridging the gap of platelet inhibition in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI). The study aimed to investigate the efficacy and safety of this alternative oral administration strategy by performing a meta-analysis of available randomized clinical trials (RCTs). PubMed, Embase, the Cochrane Library and Web of Science medical literature databases were searched for RCTs comparing crushed/chewed vs. integral administration of loading dose potent P2Y₁₂ inhibitors in patients with STEMI undergoing pPCI with no language restrictions from inception to January 20th, 2021. The primary efficacy endpoints of high on treatment platelet reactivity (HPR) and P2Y₁₂ reaction units (PRU) at 1 hour together with safety and additional clinical endpoints were evaluated by pooled odds ratio (OR) or mean differences (MD) with 95% confidence intervals (95% CI). A total of 973 patents in six RCTs were eligible for analysis, while 876 patients present baseline and procedural characteristics. HPR and PRU at 1 hour were significantly reduced in the group receiving crushed/chewed P2Y₁₂ inhibitors compared with integral tablets (OR 0.28, 95% CI 0.16 to 0.49, P < .0001; MD -60.62, 95% CI -97.06 to -24.19, P = .001, respectively). Safety endpoints of major bleeding (OR 0.54, 95% CI 0.11 to 2.73, P = .46) and any bleeding (OR 0.84, 95% CI 0.43 to 1.64, P = .61), as well as additional clinical endpoints of cardiovascular death, myocardial infarction, and stroke were not affected by the oral administration strategy. In STEMI patients undergoing pPCI, crushed or chewed administration of potent P2Y₁₂ inhibitors are associated with enhanced early platelet inhibition and appear to be safe. The clinical profile transformed from this pharmacodynamic benefit need to be determined by further researches.

Clinical efficacy and safety of tirofiban combined with conventional dual antiplatelet therapy in ACS patients undergoing PCI

Challenges remain for clinicians over balancing the efficacy of active antithrombotic therapy and simultaneous bleeding reduction in patients. The clinical data of 347 patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) were retrospectively analyzed. On the basis of the given tirofiban, the patients were assigned into three different dose groups: high dose group (group H), medium dose group (group M), and low dose group (group L). The tirofiban efficacy was evaluated in terms of major adverse cardiovascular event (MACE) parameters and lab endpoints, including platelet count and function. The tirofiban safety was assessed by the occurrence of bleeding events. The patients were followed up for 1 month after the PCI. No significant difference in MACE events was evident among these groups (p > 0.05). Groups H and M reported an obvious reduction in platelet count (p < 0.05 for both) and an increased platelet inhibition rate (p < 0.05 for both). Group H showed a higher rate of total bleeding events than the other groups (Group H vs. Group M: 34.4% vs. 16.5%; Group H vs. Group L: 34.4% vs. 10.3%; p < 0.05 for both). A proper administration of a low dose of tirofiban may be a superior alternative in treating ACS patients, which can produce a similar favorable clinical outcome and a decrease in bleeding complication.

Not-high before-treatment platelet reactivity in patients with STEMI: prevalence, clinical characteristics, response to therapy and outcomes

Platelet reactivity (PR) has been indicated as a pathophysiological key element for ST-Elevation Myocardial Infarction (STEMI) development. Patients with not-high before-treatment platelet reactivity (NHPR) have been poorly studied so far. The aim of this study is to investigate the prevalence, clinical characteristics, response to therapy and outcomes of baseline prior to treatment NHPR among patients with STEMI undergoing primary PCI.We analyzed the data from 358 STEMI patients with assessment of PR by VerifyNow before P2Y₁₂ inhibitor loading dose (LD). Blood samples were obtained at baseline, and after 1 hour, 2 hours, 4-6 hours and 8-12 hours after LD. High platelet reactivity (HPR) was defined as Platelet Reactivity Unit values ≥208, while patients with values <208 at baseline were defined as having NHPR.Overall, 20% patients had NHPR. Age and male gender both resulted independent predictors of NHPR, even after propensity score adjustment. The percentage of inhibition of PR after ticagrelor or prasugrel LD was similar between HPR and NHPR patients at each time point. However, patients with HPR showed worse in-hospital clinical outcomes, and the composite adverse outcome endpoint of death, reinfarction, stroke, acute kidney injury or heart failure was significantly higher (10.0% vs 1.4%; p = .017) as compared with the NHPR group.In conclusion, a significant proportion of patients presenting with STEMI has a baseline NHPR that is associated with better in-hospital outcomes as compared with patients with HPR. Further studies are needed to better elucidate the potential therapeutic implications of NHPR in terms of secondary prevention.

Bridging the gap: Current and future insights for improving suboptimal platelet inhibition in STEMI

Antiplatelet therapy is one of the cornerstones in the acute treatment of patients with ST-elevation myocardial infarction (STEMI) who undergo primary percutaneous coronary intervention (PCI). However, hemodynamic changes and delayed intestinal absorption of P2Y₁₂ inhibitors leads to a delay in the onset of antiplatelet effects resulting in a gap of platelet inhibition. Several strategies have been proposed to bridge this gap, such as pre-hospital administration of antiplatelet therapy, higher loading doses of P2Y₁₂ inhibitors, crushing or chewing tablets, subcutaneous or intravenous administration of platelet inhibitors, or use of pain relievers alternative to opioids that do not delay intestinal absorption of oral platelet inhibitors. These strategies may improve platelet inhibition with the goal of optimizing clinical outcomes in the acute phase of STEMI. In this review we present current and future insights for bridging the gap in platelet inhibition in STEMI patients undergoing primary PCI.

Unravelling the puzzle of antithrombotic therapies for complex percutaneous coronary intervention

Percutaneous coronary intervention (PCI) has remarkably evolved in the last decades. This has resulted in a larger number of patients treated with PCI, including those with more complex anatomic lesions. Several studies demonstrated that PCI involving complex lesions is associated with increased rate of procedural complications and adverse clinical outcomes. In this setting, optimal adjunctive antithrombotic regimens still need to be defined. In this review, we sought to summarize and discuss the recent evidence deriving from analyses appraising antithrombotic therapies in patients undergoing complex PCI.

Cangrelor, Tirofiban, and Chewed or Standard Prasugrel Regimens in Patients With ST-Segment-Elevation Myocardial Infarction: Primary Results of the FABOLUS-FASTER Trial

Supplemental Digital Content is available in the text.

Background:

Standard administration of newer oral P2Y₁₂ inhibitors, including prasugrel or ticagrelor, provides suboptimal early inhibition of platelet aggregation (IPA) in patients with ST-segment–elevation myocardial infarction undergoing primary percutaneous coronary intervention. We aimed to investigate the effects of cangrelor, tirofiban, and prasugrel, administered as chewed or integral loading dose, on IPA in patients undergoing primary percutaneous coronary intervention.

Methods:

The FABOLUS-FASTER trial (Facilitation Through Aggrastat or Cangrelor Bolus and Infusion Over Prasugrel: A Multicenter Randomized Open-Label Trial in Patients with ST-Elevation Myocardial Infarction Referred for Primary Percutaneous Intervention) is an investigator-initiated, multicenter, open-label, randomized study. A total of 122 P2Y₁₂-naive patients with ST-segment–elevation myocardial infarction were randomly allocated (1:1:1) to cangrelor (n=40), tirofiban (n=40) (both administered as bolus and 2-hour infusion followed by 60 mg of prasugrel), or 60-mg loading dose of prasugrel (n=42). The latter group underwent an immediate 1:1 subrandomization to chewed (n=21) or integral (n=21) tablets administration. The trial was powered to test 3 hypotheses (noninferiority of cangrelor compared with tirofiban using a noninferiority margin of 9%, superiority of both tirofiban and cangrelor compared with chewed prasugrel, and superiority of chewed prasugrel as compared with integral prasugrel, each with α=0.016 for the primary end point, which was 30-minute IPA at light transmittance aggregometry in response to 20 μmol/L adenosine diphosphate.

Results:

At 30 minutes, cangrelor did not satisfy noninferiority compared with tirofiban, which yielded superior IPA over cangrelor (95.0±8.9 versus 34.1±22.5; P<0.001). Cangrelor or tirofiban were both superior to chewed prasugrel (IPA, 10.5±11.0; P<0.001 for both comparisons), which did not provide higher IPA over integral prasugrel (6.3±11.4; P=0.47), despite yielding higher prasugrel active metabolite concentration (ng/mL; 62.3±82.6 versus 17.1±43.5; P=0.016).

Conclusions:

Cangrelor provided inferior IPA compared with tirofiban; both treatments yielded greater IPA compared with chewed prasugrel, which led to higher active metabolite concentration but not greater IPA compared with integral prasugrel.

Registration:

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02978040; URL: https://www.clinicaltrialsregister.eu; EudraCT 2017-001065-24.

Facilitation Through Aggrastat or Cangrelor Bolus and Infusion Over PrasugreL: a MUlticenter Randomized Open-label Trial in PatientS with ST-elevation Myocardial InFarction Referred for PrimAry PercutaneouS InTERvention (FABOLUS FASTER) Trial: Design and Rationale : The FABOLUS FASTER Trial

Antithrombotic therapy is a critical component of the management of ST-elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention (PCI). Rapid and profound inhibition of platelet reactivity has been shown to mitigate the ischemic risks and improve myocardial salvage. High residual platelet reactivity (HRPR) has been reported up to 4 or 6 h after loading dose of prasugrel or ticagrelor; therefore, multiple alternative strategies, including crushed or chewed oral tables or intravenous agents, have been investigated to provide a more rapid and sustained inhibition of platelet function and bridge the initial treatment gap. The FABOLUS FASTER is the first investigator-initiated, multicentre, open-label, prospective, randomized study to directly compare the pharmacodynamics effects of cangrelor, tirofiban, chewed or integer prasugrel. This study will add new insights in the management of antiplatelet therapy in patients with STEMI undergoing primary PCI and might be hypothesis-generating for future clinical trials in this field. The trial is registered on clinicaltrials.gov NCT02978040, and EudraCT 2017-001065-24.

P2Y12 inhibitors for the treatment of acute coronary syndrome patients undergoing percutaneous coronary intervention: current understanding and outcomes

Introduction: Inhibition of P2Y₁₂ platelet receptors consists a crucial target of pharmacologic treatment in acute coronary syndrome patients. Several controversial issues however still remain and these are analyzed.Areas covered: The significance of early and strong platelet inhibition in the early phase of STEMI and the role of pretreatment are discussed. Concerns regarding morphine administration are raised. The role of crushing integral tablets to expedite the onset of action of oral P2Y₁₂ inhibitors is emphasized. New data on the intravenous cangrelor are reported. Antiplatelet therapies as adjunct to thrombolysis, as well as the role of de-escalation antiplatelet therapy are analyzed.Expert opinion: Pharmacodynamic studies convincingly demonstrate a gap in the onset of antiplatelet action in STEMI cases, even when prasugrel or ticagrelor loading dose is used. The clinical benefit, however, of the early platelet inhibition and pretreatment is not entirely clear. Morphine delays the onset of action of oral agents, while this is expedited by crushing the integral tablets. Cangrelor devoids of these deficiencies by achieving fast and strong platelet inhibition in all clinical scenarios. Concomitant administration of novel antiplatelet agents with thrombolysis and de-escalation of antiplatelet treatment necessitate further study to reach definite conclusion.