Bioavailability of aspirin in fasted and fed states of a novel pharmaceutical lipid aspirin complex formulation

Rapid identification of potential nonsteroidal anti-inflammatory drug overdose-induced liver toxicity and prediction of follow-up exposure: Integrating bioanalytical and population pharmacokinetic assay

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most frequently used drugs that can cause liver toxicity. The aim of this study was to integrate bioanalytical and population pharmacokinetic (PopPK) assay to rapidly screen and quantify the concentrations of NSAIDs in plasma and monitor clinical safety. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous quantification of acetaminophen (APAP), flurbiprofen (FLB), aspirin (ASP), and ibuprofen (IBP), four commonly used NSAIDs. The PopPK model of the signature toxicant was analyzed based on the published literature. The LC-MS/MS method was successfully validated and applied to determine NSAID concentrations in patient plasma samples. APAP, ASP, and IBP data were best fitted using a one-compartment model, and FLB data were best fitted using a two-compartment model. Bootstrapping and visual predictive checks suggested that a robust and reliable pharmacokinetic model was developed. A fast, simple, and sensitive LC-MS/MS method was developed and validated for determining APAP, FLB, ASP, and IBP in human plasma. Combined with the PopPK model, this method was applied to rapidly analyze the concentrations of NSAIDs in clinical samples from patients presenting to the emergency department with acute liver dysfunction and monitored NSAIDs clinical safety.

Age and Aspirin Dosing in Secondary Prevention of Atherosclerotic Cardiovascular Disease

BACKGROUND

In patients with atherosclerotic cardiovascular disease, increasing age is concurrently associated with higher risks of ischemic and bleeding events. The objectives are to determine the impact of aspirin dose on clinical outcomes according to age in atherosclerotic cardiovascular disease.

METHODS AND RESULTS

In the ADAPTABLE (Aspirin Dosing: A Patient-Centric Trial Assessing Benefits and Long-Term Effectiveness) trial, patients with atherosclerotic cardiovascular disease were randomized to daily aspirin doses of 81 mg or 325 mg. The primary effectiveness end point was death from any cause, hospitalization for myocardial infarction, or hospitalization for stroke. The primary safety end point was hospitalization for bleeding requiring transfusion. A total of 15 076 participants were randomized to aspirin 81 mg (n=7540) or 325 mg (n=7536) daily (median follow-up: 26.2 months; interquartile range: 19.0-34.9 months). Median age was 67.6 years (interquartile range: 60.7-73.6 years). Among participants aged <65 years (n=5841 [38.7%]), a primary end point occurred in 226 (7.54%) in the 81 mg group, and in 191 (6.80%) in the 325 mg group (adjusted hazard ratio [HR], 1.23 [95% CI, 1.01-1.49]). Among participants aged ≥65 years (n=9235 [61.3%]), a primary end point occurred in 364 (7.12%) in the 81 mg group, and in 378 (7.96%) in the 325 mg group (adjusted HR, 0.95 [95% CI, 0.82-1.10]). The age-dose interaction was not significant (P=0.559). There was no significant interaction between age and the randomized aspirin dose for the secondary effectiveness and the primary safety bleeding end points (P>0.05 for all).

CONCLUSIONS

Age does not modify the impact of aspirin dosing (81 mg or 325 mg daily) on clinical end points in secondary prevention of atherosclerotic cardiovascular disease.

Daily low-dose aspirin and incident type 2 diabetes in community-dwelling healthy older adults: a post-hoc analysis of efficacy and safety in the ASPREE randomised placebo-controlled trial

BACKGROUND

Inflammation has been implicated in the pathogenesis of diabetes. This study investigated the randomised treatment effect of low-dose aspirin on incident type 2 diabetes and fasting plasma glucose (FPG) concentrations among older adults.

METHODS

ASPREE was a double-blind, placebo-controlled trial of daily oral low-dose aspirin. The study population included community-dwelling individuals aged 70 years or older (≥65 years for US minority ethnic groups) in the USA and Australia who were free of cardiovascular disease, independence-limiting physical disability, or dementia. For the post-hoc analysis, we excluded participants with diabetes at baseline or with incomplete or missing incident diabetes data during follow-up. Participants were randomly assigned 1:1 to oral 100 mg daily enteric-coated aspirin or placebo. Incident diabetes was defined as self-reported diabetes, commencement of glucose-lowering medication, or a FPG concentration of 7·0 mmol/L or more assessed at annual follow-up visits among participants with no diabetes at baseline. We used Cox proportional hazards models and mixed-model repeated measures to assess the effect of aspirin on incident diabetes and FPG concentrations in the intention-to-treat population. We assessed major bleeding in participants who had taken at least one dose of study medication.

FINDINGS

Between March 10, 2010, and Dec 24, 2014, a total of 16 209 participants were included (8086 [49·9%] randomly assigned to aspirin and 8123 [50·1%] randomly assigned to placebo). During a median follow-up of 4·7 years (IQR 3·6-5·7), 995 (in 6·1% individuals) incident cases of type 2 diabetes were recorded (459 in the aspirin group and 536 in the placebo group). Compared with placebo, the aspirin group had a 15% reduction in risk of incident diabetes (hazard ratio 0·85 [95% CI 0·75 to 0·97]; p=0·013) and a slower rate of increase in FPG concentration at year 5 (between-group difference estimate -0·048 mmol/L [95% CI -0·079 to -0·018]; p=0·0017). Major bleeding (major gastrointestinal bleeding, intracranial bleeding, and clinically significant bleeding at other sites) occurred in 510 (3·2%) of 16 104 participants (300 [3·7%] in the aspirin group and 210 [2·6%] in the placebo group). Compared with placebo, the aspirin group had a 44% increase in risk of major bleeding (hazard ratio 1·44 [95% CI 1·21 to 1·72]; p<0·0001).

INTERPRETATION

Aspirin treatment reduced the incidence of type 2 diabetes and slowed the increase in FPG concentration but increased major bleeding among community-dwelling older adults. Given the increasing prevalence of type 2 diabetes among older adults, the potential for anti-inflammatory agents such as aspirin to prevent type 2 diabetes or improve glucose levels warrants further study with a comprehensive assessment of all potential safety events of interest.

FUNDING

US National Institute on Aging, US National Cancer Institute, National Health and Medical Research Council of Australia, Monash University, and the Victorian Cancer Agency.

An update on novel therapies for treating patients with arterial thrombosis

INTRODUCTION

Antithrombotic therapy field is undergoing rapid and significant changes during the past decade. In addition to new therapeutic strategies with existing targets, investigators are exploring the potential use of new targets to address unmet needs to treat patients with arterial diseases.

AREAS COVERED

We aim to provide an update on and a comprehensive review of the antithrombic agents that are being explored in patients with arterial diseases. We discuss latest developments with respect to upstream antiplatelet agents, and collagen and thrombin pathway inhibitors. We searched PubMed databases for English language articles using keywords: antiplatelet agents, thrombin pathway inhibitors, collagen receptors, arterial disease.

EXPERT OPINION

Despite implementation of potent P2Y12 inhibitors, there are numerous unmet needs in the treatment of arterial diseases including ceiling effect of currently available antiplatelet agents along with and an elevated risk of bleeding. The latter observations encouraged investigators to explore new targets that can attenuate the generation of platelet-fibrin clot formation and subsequent ischemic event occurrences with minimal effect on bleeding. These targets include collagen receptors on platelets and thrombin generation including FXa, FXIa, and FXIIa. In addition, investigators are studying novel antiplatelet agents/strategies to facilitate upstream therapy in high-risk patients.

Interactions between selected over-the-counter drugs and food: clinical relevance and prevention

The use of medicines is associated with both therapeutic and adverse effects and interactions. In particular, interactions between drugs and food are common, and can either enhance the action of drugs or diminish their effect. Health professionals have a responsibility to screen for and educate patients about food-drug interactions, as well as to assist in decreasing their occurrence. The aim of this study was to identify any interactions present between food and selected over-the-counter (OTC) drugs. Sixty-five publications out of a potential 1112 found in the search were included in the study and among them 28 concerned painkillers, 6 - antihistamines, 4 - nasal decongestants, 10 were for proton pump inhibitors and for iron and 8 for sildenafil. Interactions between food and OTC drugs do exist. These drugs should not be taken regardless of the meal. Providing relevant information to the patient will increase drug safety and efficacy.

Pharmacokinetic and Pharmacodynamic Profile of a Novel Phospholipid Aspirin Formulation

Aspirin is one of the most widely used medicines. Although aspirin is commonly utilized for the treatment of several medical conditions, its broadest uptake is for the prevention of recurrent ischemic events in patients with atherosclerotic disease. Its mechanism of action of inhibiting platelet activation via blockade of thromboxane A2 production is unique and is not covered by any other antiplatelet agents. While plain, uncoated, immediate-release aspirin is used in acute settings to help assure rapid absorption, enteric-coated aspirin formulations dominate current chronic use, particularly in North America, including for secondary prevention of cardiovascular events. The unmet needs with current aspirin formulations include a high risk of gastrointestinal (GI) adverse events with plain aspirin, which enteric-coated formulations are not able to overcome, and subject to erratic absorption leading to reduced drug bioavailability. These observations underscore the need for aspirin formulations with a more favorable safety and efficacy profile. Phospholipid-aspirin complex (PL-ASA) is a novel formulation designed to address these needs. It is associated with reduced local acute GI injury compared with plain aspirin, and predictable absorption resulting in more reliable platelet inhibition compared with enteric-coated tablets. This review explores the rationale and pharmacologic profile of PL-ASA intended to address the unmet needs for aspirin therapy.

Aspirin for Primary Cardiovascular Prevention in Patients with Diabetes: Uncertainties and Opportunities

The use of the antiplatelet agent aspirin (acetylsalicylic acid) was previously routinely recommended for the primary prevention of cardiovascular (CV) events in patients with diabetes, but recent large-scale randomized trials have failed to demonstrate a sizeable net clinical benefit with a once-daily, low-dose (81–100 mg) regimen in this population. Previous pharmacokinetic and pharmacodynamic studies have suggested that the aspirin formulation (enteric-coated) and dosing schedule (once daily) studied in randomized trials for primary prevention of CV events defining contemporary clinical practice may not leverage the full potential of the drug, particularly in patients with diabetes. Indeed, the diabetic platelets bear characteristics that increase their thrombotic potential and alter their pharmacologic response to the drug. Consequently, the appropriateness of studying a uniform aspirin regimen in landmark primary prevention trials needs to be revisited. In this review, we present the evidence showing that diabetes not only increases baseline platelet reactivity, but also alters platelet response to aspirin through different mechanisms including a faster platelet turnover rate. Obesity, which is frequently associated with diabetes, also impacts its pharmacokinetics via an increase in distribution volume. Small-scale pharmacokinetic and pharmacodynamic studies have suggested that the relative aspirin resistance phenotype observed in patients with diabetes may be reversed with a twice-daily dosing schedule, and with nonenteric-coated aspirin formulations. Properly powered randomized controlled trials investigating the efficacy and safety of aspirin dosing schedules and formulations tailored to the population of patients with diabetes are urgently required to optimize patient care.

Appraising the contemporary role of aspirin for primary and secondary prevention of atherosclerotic cardiovascular events

INTRODUCTION

Although the role of aspirin for primary prevention of atherosclerotic cardiovascular disease (ASCVD) has been disputed, its use in secondary ASCVD prevention is well established. Recent trials of primary prevention do not suggest a significant net benefit with aspirin, whereas accruing evidence supports adopting aspirin-free strategies in the context of potent P2Y₁₂ inhibition for the secondary prevention of selected patients undergoing percutaneous coronary intervention.

AREAS COVERED

This updated review aims at summarizing and appraising the pharmacological characteristics and the contemporary role of aspirin for the primary and secondary prevention of ASCVD.

EXPERT OPINION

Recent trials and metanalyses in the context of primary prevention highlighted a modest reduction in ischemic events with aspirin use, counterbalanced by a significant increase in bleeding events. However, ongoing studies on cancer prevention could modify the current paradigm of the unfavorable benefit-risk ratio of aspirin in patients with no overt ASCVD. Conversely, aspirin use is crucial for secondary ASCVD prevention, both in chronic and acute coronary syndromes. Nevertheless, after a brief period of dual antiplatelet therapy, patients at high bleeding risk may benefit from discontinuation of aspirin if a P2Y₁₂ inhibitor is used, hence reducing the bleeding risk with no rebound in thrombotic events.

Aspirin, sodium benzoate and sodium salicylate reverse resistance to colistin in Enterobacteriaceae and Pseudomonas aeruginosa

BACKGROUND

MDR bacterial infections are currently a serious problem for clinicians worldwide. Klebsiella pneumoniae and Enterobacter spp., among Enterobacteriaceae, and Pseudomonas aeruginosa, are part of the group of ESCAPE pathogens or bacteria that 'escape' from common antibacterial treatments. The lack of effectiveness of the first common line of antibiotics has led to the search for new therapies based on older antibiotics, such as colistin.

OBJECTIVES

We searched for new enhancers of the action of colistin against MDR Gram-negative bacteria that can be easily applicable to clinical treatments.

METHODS

Colistin MICs were determined alone and with the protonophores CCCP, sodium benzoate, sodium salicylate and aspirin using the broth microdilution method and FIC indexes were calculated to assess synergy between colistin and each chemical. Time-kill assays of colistin with and without protonophores were performed to determine the bactericidal action of combinations of colistin with protonophores. Likewise, the effect of sucrose, l-arginine and l-glutamic acid on the MICs of colistin alone and combined with each protonophore was assessed.

RESULTS

It was found that sodium benzoate, sodium salicylate and aspirin, at concentrations allowed for human and animal use, partially or totally reversed resistance to colistin in P. aeruginosa and highly resistant enterobacterial strains. The mechanism of action could be related to their negative charge at a physiological pH along with their lipid-soluble character.

CONCLUSIONS

Sodium benzoate, sodium salicylate and aspirin are good enhancers to use in antibiotic therapies that include colistin.

The Future of Aspirin Therapy in Cardiovascular Disease

Much has been written about the demise of aspirin (ASA) but reports of its death are premature. The drug remains one of the most widely prescribed by physicians worldwide. It is cheap, familiar, and effective for a variety of uses, including in patients with acute or prior myocardial infarction, ischemic stroke, peripheral artery disease, and percutaneous or surgical revascularization procedures, as well as for use for pain and fever relief. Beyond physician prescription or recommendation, over the counter use of ASA is common, including for primary cardiovascular prevention, though this decision really should involve a discussion of risks and benefits with a physician. ASA is an essential member of the duo that makes up dual antiplatelet therapy (a P2Y₁₂ inhibitor plus ASA) and also dual pathway inhibition (vascular dose rivaroxaban plus ASA), and data for both approaches are growing. Furthermore, research is ongoing as to the optimal dosing frequency (once vs twice daily), potentially safer gastrointestinal delivery, and possibly more effective formulations in terms of platelet inhibition. One goal of ASA research is to try to reduce bleeding complications that are a risk with all anti-thrombotic therapies. Although its exact roles will continue to evolve, the future for ASA remains bright.

The Influence of Lipid Excipients on Platelet Function and the Pharmacodynamic Effects of Aspirin

ABSTRACT

The combination of pharmaceutical lipid excipients with aspirin in a novel liquid oral formulation (Vazalore) limits gastrointestinal toxicity of aspirin. This study was performed to determine whether the lipid excipients influence the pharmacodynamic effects of aspirin and determine whether the excipients directly affect platelet function. The pharmacodynamic effects of aspirin were assessed over a range of concentrations designed to exert limited to maximal inhibition of cyclooxygenase-1 (COX1) necessary for thromboxane A2 production. Platelet aggregation induced by arachidonic acid and assessed with the use of light transmission aggregometry (LTA) was used as a direct measure of the inhibition of COX1 by aspirin. Flow cytometry was used to assess the direct effect of excipients on platelet function. Twice the ratio of lipid excipient to aspirin used in the formulation of the novel oral agent was used. Blood was taken from 20 healthy subjects and anticoagulated with trisodium citrate (3.2%, 1:10 v/v). Aspirin and excipients were added in vitro and incubated for 10 minutes before performance of LTA and flow cytometry. The excipients did not limit the pharmacodynamic effects of aspirin. When the extent of inhibition of platelet aggregation was limited, the excipients tended to enhance pharmacodynamic effects. The excipients did not activate platelets in the absence of agonist and did not alter activation of platelets in response to adenosine diphosphate, arachidonic acid, thrombin, or convulxin (a collagen mimetic). Lipid excipients used in an oral formulation of aspirin do not impair the pharmacodynamic effects of aspirin and do not alter platelet function.

Antithrombotic Therapy for Atherosclerotic Cardiovascular Disease Risk Mitigation in Patients With Coronary Artery Disease and Diabetes Mellitus

Patients with diabetes mellitus (DM) are characterized by enhanced thrombotic risk attributed to multiple mechanisms including hyperreactive platelets, hypercoagulable status, and endothelial dysfunction. As such, they are more prone to atherosclerotic cardiovascular events than patients without DM, both before and after coronary artery disease (CAD) is established. In patients with DM without established CAD, primary prevention with aspirin is not routinely advocated because of its increased risk of major bleeding that largely offsets its ischemic benefit. In patients with DM with established CAD, secondary prevention with antiplatelet drugs is an asset of pharmacological strategies aimed at reducing the risk of atherosclerotic cardiovascular events and their adverse prognostic consequences. Such antithrombotic strategies include single antiplatelet therapy (eg, with aspirin or a P2Y₁₂ inhibitor), dual antiplatelet therapy (eg, aspirin combined with a P2Y₁₂ inhibitor), and dual-pathway inhibition (eg, aspirin combined with the vascular dose of the direct oral anticoagulant rivaroxaban) for patients with chronic ischemic heart disease, acute coronary syndromes, and those undergoing percutaneous coronary intervention. Because of their increased risk of thrombotic complications, patients with DM commonly achieve enhanced absolute benefit from more potent antithrombotic approaches compared with those without DM, which most often occurs at the expense of increased bleeding. Nevertheless, studies have shown that when excluding individuals at high risk for bleeding, the net clinical benefit favors the use of intensified long-term antithrombotic therapy in patients with DM and CAD. Several studies are ongoing to establish the role of novel antithrombotic strategies and drug formulations in maximizing the net benefit of antithrombotic therapy for patients with DM. The scope of this review article is to provide an overview of current and evolving antithrombotic strategies for primary and secondary prevention of atherosclerotic cardiovascular events in patients with CAD and DM.