Pharmacokinetic evaluation of rivaroxaban for the treatment of acute coronary syndromes

INTRODUCTION: Arterial and venous thrombotic states, including myocardial infarction (MI), stroke and deep vein thrombosis with subsequent pulmonary embolism, are a significant cause of cardiovascular mortality and morbidity. Factor Xa (FXa) plays a pivotal role in thrombus formation. Its inhibition following acute coronary syndromes (ACS) blocks amplification of thrombin generation and subsequent clot formation, resulting in a risk reduction in recurrent MI, stroke and death. For this reason, a predictable form of oral anticoagulation continues to be an ongoing need. Rivaroxaban , the first oral FXa inhibitor, acts by direct inhibition of FXa and does not require an antithrombin cofactor for its activity. AREAS COVERED: This paper describes the pharmacokinetics (PK) of low-dose rivaroxaban tested in patients with ACS. Age, gender, renal function and body weight have no clinically significant effects on the PK of the drug in treatment of ACS. Caution should be maintained during co-administration of strong CYP3A4 inducers and inhibitors. Among patients with moderate and severe hepatic impairment and in those with associated coagulopathies, rivaroxaban however is contraindicated. EXPERT OPINION: The mortality benefit with low-dose rivaroxaban in ACS patients was first demonstrated in ATLAS ACS2 TIMI-51 trial. With its rapid oral bioavailability, predictable PK, low drug-drug interaction and no need for monitoring, the use of low-dose rivaroxaban in addition to dual antiplatelet therapy offers an appealing new option in improving outcomes following ACS in the modern era of novel oral FXa inhibitors.     

Review of pharmacoeconomic evaluation of genotype-guided antiplatelet therapy

Introduction: Clopidogrel is an antiplatelet agent widely prescribed for acute coronary syndrome (ACS), and it is activated by the CYP enzyme system to active metabolite. CYP2C19 loss-of-function (LOF) allele(s) affect the responsiveness of clopidogrel, but not the new antiplatelet agents (prasugrel and ticagrelor). We reviewed the pharmacoeconomic studies on genotype-guided use of new antiplatelet agents.

Areas covered: A literature search was conducted between the period of 2000 and 2014. Seven studies including cost-effectiveness and risk-benefit analyses of CYP2C19 genotype-guided antiplatelet therapy in ACS patients were reviewed. Genotype-guided prasugrel was found to be cost-effective when compared with universal antiplatelet therapy in four studies. Three studies showed genotype-guided ticagrelor to be cost-effective in ACS patients with percutaneous coronary intervention (PCI), and universal ticagrelor to be cost-effective in ACS patients. Drug cost of antiplatelet agents and relative risk of the new antiplatelet versus clopidogrel for clinical events were common influential factors of cost-effectiveness analyses.

Expert opinion: All studies in the present review focused on selecting antiplatelet agents for carriers of CYP2C19 LOF allele(s). Cost-effectiveness of genotype-guided use of antiplatelets was demonstrated in high-risk ACS patients.     

Antiplatelet therapy in acute coronary syndromes

Introduction: Coronary thrombosis is a frequent cause of death and myocardial infarction most often explained by superimposition of a platelet-rich thrombus on existing coronary artery disease. Therefore, antiplatelet drugs are essential in the treatment and secondary prevention of acute coronary syndromes (ACS) and during percutaneous coronary intervention. Several novel antiplatelet drugs are now available.

Areas covered: For several years, aspirin and clopidogrel remained the cornerstone of treatment for ACS. However, prasugrel and ticagrelor have a more consistent, faster-acting and more potent antiplatelet effect than clopidogrel, which translates into improved clinical outcomes, although at the expense of an increased bleeding risk. Importantly, some patients experience cardiovascular events despite current antiplatelet treatment, because platelet activation may occur via pathways not inhibited by these agents. Therefore, improved antiplatelet strategies are warranted.

Expert opinion: Despite undisputable benefits of current antiplatelet strategies, a considerable number of patients continue to experience adverse thrombotic events, although clinical outcomes have been improved with new oral P2Y₁₂ antagonists. New drugs have been developed, including intravenous P2Y₁₂ antagonists and oral antagonist targeting the protease-activated receptor-1 platelet activation pathway stimulated by thrombin. This review provides an overview of current and novel antiplatelet strategies and also discusses unmet needs related to antiplatelet therapy for ACS.     

Developments in antiplatelet therapy for acute coronary syndromes and considerations for long-term management

ABSTRACT

Objective: This article reviews the currently available antiplatelet therapies and emerging investigational drugs in the treatment of acutecoronary syndrome (ACS), and considerations for primary and secondary prevention in the long-term management of ACS patients undergoing percutaneous coronary intervention (PCI).

Research design and methods: Primary studies and reviews in the peer-reviewed, English-language literature were identified through searches of MEDLINE (1966–2008) using the terms ‘acute coronary syndrome’, ‘antiplatelet’, ‘aspirin’, ‘long-term management’, ‘P2Y₁₂ receptor’, and ‘thienopyridine’. Additional references were obtained by searching the reference lists of the identified articles. Articles were included if they were recently published and pertinent, patient-focused, and authors were recognized as leaders in the field. Current review is limited by literature search on single database.

Results: Platelets play a major role in atherogenesis and the formation of thrombi, the main events in the pathogenesis of ACS. Although aspirin is an effective antiplatelet agent, efficacy and safety data from a number of randomized clinical trials on atherothrombotic disease support the use of dual antiplatelet therapies such as aspirin and thienopyridines over single antiplatelet therapy for ACS and up to 1?year following ACS. Antiplatelet agents reduce, but do not eliminate, ischemic events after ACS due, in part, to variable individual response (or resistance) in antiplatelet agents, non-compliance, progression of atherosclerosis, modest inhibition of platelet aggregation (IPA) levels and other factors. Several antiplatelet agents, including novel P2Y₁₂-receptor antagonists and thrombin-receptor antagonists, are currently under investigation for ACS and primary and secondary prevention in the long-term management of patients undergoing PCI.

Conclusions: Current antiplatelet therapies have clinical benefits such as reducing immediate and long-term cardiovascular risk, but substantial residual risk remains indicating a need for new therapeutic agents. Additional large randomized trials are necessary to determine the most appropriate treatment regimens for ACS patients.     

Safety evaluation of tirofiban

Importance of the field: Heightened platelet activity is pivotal in the thrombosis underlying acute coronary syndrome (ACS). The glycoprotein IIb/IIIa inhibitor tirofiban is a powerful platelet inhibitor with demonstrated efficacy and safety across the spectrum of ACS. Despite tirofiban's impact on the platelet compared with placebo, only an excess in minor and importantly not major bleeding has been observed. Thrombocytopenia with tirofiban seems to be extremely rare and immediately reversible on infusion discontinuation.

Areas covered in this review: The review includes the rationale for potent antiplatelet therapy in the management of ACS, particularly patients at high risk for ischemic complications. Additionally, it provides an overview of tirofiban's pharmacology and summary of the clinical efficacy and safety data of two dosing regimens.

What the reader will gain: The reader will gain a perspective on the efficacy and safety data from the key trials of tirofiban.

Take home message: Tirofiban is safe and effective in patients with ACS. The single bolus dose regimen produces potent platelet inhibition resulting in significant improvement in clinical events over placebo when initiated just prior to percutaneous coronary intervention and at first medical contact. When compared with abciximab, tirofiban demonstrates similar efficacy though significantly lower rates of thrombocytopenia.     

Novel oral anticoagulants: focus on the direct factor Xa inhibitor darexaban

Introduction: Inhibition of the pathways of anticoagulation is widely used for the prevention and treatment of arterial and venous thrombosis. Vitamin K antagonists (VKAs) have been the mainstay of oral anticoagulation for more than 60 years. Their safety and effectiveness have been established in multiple clinical trials, for a variety of clinical indications. However, there are several limitations to the use of VKAs including delayed onset of action and dosage titration, numerous food and drug interactions and need for regular laboratory monitoring. To overcome some of the limitations of traditional agents, new oral anticoagulants (OACs) have been developed and evaluated.

Areas covered: In the present review article, the pharmacokinetic properties of darexaban are presented, along with the available preliminary clinical data. The performance of darexaban in respect to safety and efficacy compared with its competitors is further discussed.

Expert opinion: Darexaban is a potent direct factor Xa inhibitor that demonstrated impressive pharmacokinetic properties in pre-clinical studies. It was further successfully evaluated in the ONYX program for the prevention of venous thromboembolism in patients undergoing hip replacement. Finally, in the Phase II RUBY-1 trial, darexaban was tested on the top of standard antiplatelet therapy for the prevention of ischemic events in acute coronary syndrome (ACS) patients. Despite the fact that darexaban had a relatively uneventful clinical evaluation program, its further development was recently discontinued. This decision could probably reflect the non-favorite results in commercially attractive indications, such as secondary prevention post-ACS and the increased competition for less common or short-term indications such stroke prevention in AF or VTE prophylaxis respectively.     

Thrombin receptor antagonism –the potential of antiplatelet medication SCH 530348

Importance of the field: Coronary artery disease is a leading cause of morbidity and mortality worldwide. Platelet activation and subsequent thrombus formation play a central role in disease progression and development of acute coronary syndromes (ACS). Despite widespread use of single and dual antiplatelet therapies in atherothrombotic disease, ischemic complications remain common. Therefore, the need exists for new antiplatelet agents that are more effective, but with acceptable safety profiles (i.e., do not increase risk of bleeding). Antiplatelet agents available at present are effective in blocking the cyclo-oxygenase, ADP-mediated and final common (IIb/IIIa receptor) pathways for platelet activation. Recently, there has been more interest in inhibition of the proteinase-activated receptor-1 (PAR-1), which blocks thrombin-mediated platelet activation.

Areas covered in this review: This review covers the pharmacology, pharmacokinetics and development of the new PAR₁ antagonist, SCH 530348 in a review of all publications relevant to the topic over the last 10 years. Phase II clinical trials indicate that addition of this agent to current antiplatelet regimens may provide additional antithrombotic protection without an increase in bleeding. Results of the ongoing Phase III trials, examining the use of SCH 530348 in patients with ACS and for secondary prevention of ischemic events are anxiously awaited.

What the reader will gain: The review is a summary of all pharmacologic properties and current clinical data available on the PAR1 antagonist SCH 530348. The readers will be introduced to its novel mechanism of action, advantages over current antiplatelet agents and potential future applications should ongoing clinical trials confirm its efficacy in reducing platelet activity.

Take home message: SCH 530348 is a new, orally administered antiplatelet agent that blocks the protease-activated thrombin receptor on the platelet. Early clinical data indicate that it is associated with a lower risk of bleeding. However, its efficacy in improving clinical outcomes in patients with coronary disease remains to be confirmed in ongoing Phase III clinical trials.     

Predictors of high-cost managed care patients with acute coronary syndrome

ABSTRACT

Objective: To develop predictive models of high-cost acute coronary syndrome (ACS) patients using demographic, disease, and treatment characteristics.

Study design: This was a retrospective, administrative claims analysis utilizing pharmacy, medical, and eligibility data from a large US managed care organization.

Methods: ACS was defined by ICD-9 codes for unstable angina (UA) or acute myocardial infarction (AMI). New onset patients (without ACS claims) in the prior six months were identified for the time period 07/01/99–06/30/01, and followed up to 12 months, health plan disenrollment, or death. Cost was measured as that incurred during the initial episode plus subsequent follow-up or during the subsequent follow-up only. Patients were dichotomized as high-cost (top 20%) or low-cost (bottom 80%), based on total costs. Logistic regression was used to examine the association for being classified as high-cost.

Results: A total of 13?731 patients were included: 51.7% with UA, 39.6% with AMI and 8.7% with both UA and AMI. The mean age was 54.2 years and 68.2% were male. A number of co-morbidities (hypertension, diabetes, heart failure, etc.) predicted high-cost patients. Among medications, prior ACE inhibitor use predicted high-cost patients. While revascularization procedures, in general, were strong predictors of high-cost, revascularization during the index ACS episode (opposed to revascularization during the follow-up) decreased the odds of being high-cost (odds ratio [95% CI] 0.615 [0.506–0.748]).

Conclusion: High-cost patients with new onset ACS can be predicted by some characteristics, but many of these characteristics are non-modifiable co-morbidities. Payers and providers may find opportunities for clinical and cost-saving interventions for these patients.     

Developing drugs for use before,during and soon after percutaneous coronary intervention

Introduction: Percutaneous coronary intervention (PCI) is a milestone for treating coronary artery disease (CAD). Antithrombotic therapy is essential to prevent ischemic complications, including the microvascular no-reflow, while minimizing bleeding events.

Areas covered: This overview discusses available and developing drugs for PCI including anticoagulants, antiplatelets and treatment of no-reflow.

Expert opinion: For years unfractionated heparin (UFH) has been the unique anticoagulant to be used before and during PCI. Enoxaparin showed similar efficacy and safety, yet, based on recent trials, bivalirudin has been shown to have some benefits, particularly for patients with ST-segment elevation myocardial infarction (STEMI). The evidence concerning new anticoagulants is still preliminary, except for new oral anticoagulants, particularly rivaroxaban that showed intriguing findings and is currently under investigation. Dual antiplatelet therapy (DAPT) is the standard of care after PCI, but new developments have recently emerged. Indeed, ticagrelor and prasugrel are currently recommended over clopidogrel due to their significant reduction of ischemic events in acute coronary syndrome (ACS) whereas clopidogrel remains the choice in stable CAD. Among new agents, vorapaxar and cangrelor showed positive but limited evidence and might be considered at least in selected patients. Conversely, evidence on effective treatments for no-reflow remains limited and would require future dedicated research.     

Oral anticoagulant use in cardiovascular disorders: a perspective on present and potential indications for rivaroxaban

Background: Four non-vitamin-K-antagonist oral anticoagulants (NOACs) have been approved for use in various cardiovascular indications. The direct thrombin inhibitor dabigatran and the direct factor Xa inhibitors apixaban, edoxaban and rivaroxaban are now increasingly used in clinical practice. For some of these agents, available data from real-world studies support the efficacy and safety data in phase III clinical trials.

Objectives: This review aims to summarize the current status of trials and observational studies of oral anticoagulant use over the spectrum of cardiovascular disorders (excluding venous thrombosis), provide a reference source beyond stroke prevention for atrial fibrillation (AF) and examine the potential for novel applications in the cardiovascular field.

Methods: We searched the recent literature for data on completed and upcoming trials of oral anticoagulants with a particular focus on rivaroxaban.

Results: Recent data in specific patient subgroups, such as patients with AF undergoing catheter ablation or cardioversion, have led to an extended approval for rivaroxaban, whereas the other NOACs have ongoing or recently completed trials in this setting. However, there are unmet medical needs for several arterial thromboembolic-related conditions, including patients with: AF and acute coronary syndrome, AF and coronary artery disease undergoing elective percutaneous coronary intervention, coronary artery disease and peripheral artery disease, implanted cardiac devices, and embolic stroke of unknown source.

Conclusion: NOACs may provide alternative treatment options in areas of unmet need, and numerous studies are underway to assess their benefit–risk profiles in these settings.     

Pharmacokinetics and pharmacodynamics of ticagrelor in the treatment of cardiac ischemia

Introduction: After acute coronary syndromes (ACS), the so-called dual antiplatelet therapy (DAPT), which usually consists of low-dose of aspirin in combination with a thienopyridine (clopidogrel, prasugrel) or with a cyclopentyltriazolopyrimidine (ticagrelor), reduces the risk of ischemic events. Ticagrelor, un particular, is an effective drug as it isn’ a prodrug, doesn’t require metabolic activation and demonstrates a rapid onset and faster offset of action.

Areas covered: This article evaluates the pharmacokinetics, efficacy, safety and tolerability of ticagrelor during DAPT after ACS and its potential use beyond the canonical twelve months after PCI. The review discusses studies comparing: ticagrelor and clopidogrel (DISPERSE, DISPERSE-2, PLATO, RESPOND Trial, ONSET/OFFSET Trials), ticagrelor and placebo (PEGASUS TIMI 54 Trial).

Expert opinion: For ACS patients, the PLATO trial showed that ticagrelor was superior to clopidogrel in the reduction of cardiovascular death, myocardial infarction and stroke. PEGASUS TIMI 54 showed that patients in whom ischemic events and cardiovascular death outweigh the risk of life-threatening bleeding, may benefit from prolonged ticagrelor-based dual antiplatelet therapy, over 12 months. This strategy has been recently approved by the ACC/AHA guidelines. Further studies are needed to evaluate and eventually validate the role of the prolonged DAPT in patients treated with new generation stents.     

Changing anticoagulant paradigms for atrial fibrillation: dabigatran,apixaban and rivaroxaban

Introduction: Vitamin K antagonists (VKAs) are the main therapeutic agents used to prevent embolic events in patients with atrial fibrillation (AF). Despite their proven efficacy, VKAs are underused and have several limitations. In recent years, there has been great interest in the development of new oral anticoagulants with a more efficient pharmacological profile, first tested in venous thromboembolism prevention and later in AF.

Areas covered: The authors review the pharmacological differences between dabigatran, rivaroxaban and apixaban, and potential subgroups of patients in whom these new drugs would constitute a possible alternative to VKA therapy. Pharmacodynamic and pharmacokinetic data from each compound are analyzed in respect to their potential use in AF. This article provides an exhaustive review of the current status of this topic and the controversies still regarding each drug.

Expert opinion: Apixaban and rivaroxaban are under evaluation for thromboembolic prevention in AF; dabigatran was recently approved for this indication. Therefore, it is important to know the characteristics of these drugs as a potential alternative to VKAs.     

Effect of clopidogrel besylate on platelet reactivity in patients with acute coronary syndromes. Comparison with clopidogrel hydrogen sulfate

Objective: The efficacy of clopidogrel therapy in patients with an acute coronary syndrome (ACS) has been established using the clopidogrel hydrogen sulfate (CHS) formulation. In this study we compared the antiplatelet effectiveness of a generic clopidogrel salt, clopidogrel besylate (CB), with the original CHS in patients with an ACS.

Research design and methods: Ninety-six ACS patients were randomized to receive a 600-mg loading dose of either CHS (n = 45) or CB (n = 51), followed by 75 mg/day. Sixty-eight patients underwent a percutaneous coronary intervention (PCI), whereas 28 were treated conservatively. Platelet aggregatory response, vasodilator-stimulated phosphoprotein (VASP) phosphorylation, P-selectin expression and platelet–leucocyte conjugates were determined before clopidogrel loading (baseline), as well as at 5 days and at 1 month afterwards.

Results: No difference in the clopidogrel response variability was observed between patients receiving CHS or CB either at 5 days or at 1 month of follow-up. Similarly, no difference in the inhibition of platelet aggregation, P-selectin expression or in the platelet–leucocyte conjugates was observed between CHS and CB group during the follow-up.

Conclusions: There is no overall significant difference in the antiplatelet efficacy between CB and CHS during their administration in ACS patients for up to 1 month after the episode.     

Investigational new drugs for the treatment of acute coronary syndrome

Introduction: Ischemic heart disease is the most common cause of death worldwide. Despite improvements in interventional and pharmacological therapy for acute coronary syndrome (ACS), the risk of recurrent myocardial ischemia and mortality early after ACS remains high. Our improved understanding of the increasing role of inflammation in the pathogenesis of ACS and its relationship to atherosclerotic plaque rupture and thrombosis has led to the development of more potent anti-thrombotic and novel anti-inflammatory therapies for the treatment of ACS.

Areas covered: In this review, the authors explore: the developing pharmacotherapy in the field of cardiology for ACS; antiplatelet agents (both further development of classical modalities together with pioneering agents); evolving use of anticoagulation in its treatment, and exploration in the use of novel anti-inflammatories and biological agents.

Expert opinion: Data from trials involving the use of immunological and cellular-based treatments show promising results and herald further possible reduction in infarct burden in ACS alongside the possibility of recovery in cardiac function following infarction.     

Direct oral anticoagulants in the treatment of pulmonary embolism

Objective: The objective of this review is to examine the management strategies for pulmonary embolism (PE) with an emphasis of the role of direct oral anticoagulants (DOACs).

Methods: PubMed was searched to identify relevant journal articles published through April 2017. Additional references were obtained from articles discovered during the database search.

Results: Initial heparinization followed by long-term anticoagulation with vitamin K antagonists has been considered the mainstay for the treatment of PE. However, DOACs now offer comparably effective and potentially safer alternatives for both acute and long-term treatment of PE using a monotherapy approach without the need for initial heparinization for rivaroxaban or apixaban. Advantages to using DOACs include oral availability, rapid onset of action, minimal drug and food interactions, predictable pharmacokinetics, and lack of need for routine monitoring. Limitations of using these agents include a limited availability of assays to quickly and efficiently measure their anticoagulant effects and the lack of widely available reversal agents for the direct oral factor Xa inhibitors; although idarucizumab has recently been approved for the reversal of dabigatran’s anticoagulant effects.

Conclusions: Advantages to using DOACs render them an attractive alternative to conventional therapy in PE treatment that may simplify acute and long-term treatment paradigms, improve patient outcomes, and increase patient compliance. However, questions remain pertaining to the use of DOACs in PE patients with high-risk features and in cancer patients and fragile populations. Clinical studies are under way to address many of these issues.     

Long-term follow-up of antithrombotic management patterns in patients with acute coronary syndrome in Russia: an observational study (EPICOR-RUS study)

Objective: This study sought to describe the short- and long-term (up to 2 years) antithrombotic management patterns in a real-life setting for patients hospitalized for an acute coronary syndrome (ACS) event, and to document clinical outcomes.

Research design and methods: EPICOR-RUS was a multicenter (34 centers), prospective, observational, longitudinal cohort study conducted across Russia on antithrombotic management in hospitalized (within 24?hours of symptom onset) ACS patients with 2 year follow-up.

Clinical trial registration: NCT01373957.

Results: A total of 600 ACS patients (71.1% male, mean age 60 years) were enrolled; 599 were included for analysis. Diagnosis comprised STEMI (n?=?375, 62.6%), NSTEMI (n?=?147, 24.5%), and unstable angina (UA) (n?=?77, 12.9%). Percutaneous coronary intervention (PCI) was conducted in 64.3% of patients with STEMI (with or without thrombolysis), 36.7% with NSTEMI, and 58.4% with UA. There was undertreatment with dual antiplatelet therapy (DAPT) for STEMI, NSTEMI, and UA: 14.7%, 25.9% and 16.9% of patients, respectively, were not receiving DAPT during hospitalization, and 10.1%, 21.8% and 16.9% at discharge. Post-discharge, of the STEMI group, only 72.4% of patients who were managed by PCI and 39.8% of conservatively treated patients received DAPT at 12 months. The respective figures in the NSTEMI group were 77.3% and 26.4%. In the STEMI cohort the cumulative incidence of all-cause mortality was 3.2% at 1 year and 5.1% at 2 years of follow-up; in the NSTEMI cohort this was 2.7% and 4.8%, respectively. There were no deaths by 12 months and one death by 24 months (1.3%) in the UA population.

Conclusion: Despite evidence-based guidelines for the management of ACS, the real-world setting in Russia shows discrepancies in clinical practice, highlighting the need for improvements for the optimal management of high-risk patients with ACS.     

An early evaluation of bleeding-related hospital readmissions among hospitalized patients with nonvalvular atrial fibrillation treated with direct oral anticoagulants

Objective:

Clinical trials have demonstrated that direct oral anticoagulants (DOACs) are efficacious in reducing stroke risk among patients with nonvalvular atrial fibrillation (NVAF) with differences in the reduction of bleeding risks vs. warfarin. The objective of this study was to assess bleeding-related hospital readmissions among hospitalized NVAF patients treated with dabigatran, rivaroxaban, and apixaban in the US.

Research design and methods:

Patients (≥18 years) with a discharge diagnosis of NVAF who received apixaban, dabigatran, or rivaroxaban during hospitalization were identified from the Premier Hospital database (1 January 2012–31 March 2014) and the Cerner Health Facts hospital database (1 January 2012–31 August 2014). Patients identified from each database were analyzed separately and grouped into three cohorts depending on which DOAC was received. Patient characteristics, hospital resource use and costs, and frequency of readmissions within 1 month were evaluated.

Results:

Among study populations identified from the Premier database (N?=?74,730) and the Cerner database (N?=?14,201), patients who received apixaban were older, had greater comorbidity, and had higher stroke and bleeding risks. After controlling for patient characteristics, including comorbidity and stroke and bleeding risks, compared with patients who received apixaban during their index hospitalizations, the odds of bleeding-related hospital readmissions were significantly greater by 1.4-fold (p?<?0.01) for patients who received rivaroxaban and 1.2-fold (p?=?0.16) numerically greater for patients who received dabigatran among patients identified from the Premier Hospital database. Among patients in the Cerner Health Facts hospital database, bleeding-related hospital readmissions were significantly greater by 1.6-fold (p?=?0.04) for patients who received rivaroxaban and 1.3-fold (p?=?0.30) numerically greater for patients who received dabigatran compared to patients who received apixaban.

Limitations:

No causal relationship between treatment and outcomes can be concluded.

Conclusions:

NVAF patients using different DOACs had different characteristics, including stroke and bleeding risks. Use of rivaroxaban, compared to apixaban was associated with significantly greater risk of bleeding-related readmissions across two database claims analyses.     

New directions for pharmacotherapy in the treatment of acute coronary syndrome

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.     

Effect of various treatments on leptin,adiponectin, ghrelin and neuropeptide Y in patients with type 2 diabetes mellitus

Introduction: Several peptides are involved in the regulation of food intake and energy expenditure, among which are leptin, adiponectin, ghrelin and neuropeptide Y (NPY). These peptides may be implicated in the obesity seen in the majority of patients with type 2 diabetes mellitus (T2DM).

Areas covered: The present review considers: i) the role of leptin, adiponectin, ghrelin and NPY in patients with T2DM, and, ii) the effect of insulin as well as oral hypoglycemic, antihypertensive, hypolipidemic, antiobesity and antiplatelet agents on these peptides in patients with T2DM.

Expert opinion: Patients with T2DM have either lower or similar leptin levels, decreased adiponectin and ghrelin levels, and increased NPY circulating levels compared with nondiabetic controls. Treatment with insulin, oral hypoglycemic, antihypertensive, hypolipidemic, antiobesity and antiplatelet drugs may influence the levels of these peptides. It is not widely appreciated that several drugs commonly administered to patients with T2DM can influence adipokine levels. The clinical relevance of these effects needs to be evaluated.