Platelet and HIV Interactions and Their Contribution to Non-AIDS Comorbidities

Platelets are anucleate cytoplasmic cell fragments that circulate in the blood, where they are involved in regulating hemostasis. Beyond their normal physiologic role, platelets have emerged as versatile effectors of immune response. During an infection, cell surface receptors enable platelets to recognize viruses, resulting in their activation. Activated platelets release biologically active molecules that further trigger host immune responses to protect the body against infection. Their impact on the immune response is also associated with the recruitment of circulating leukocytes to the site of infection. They can also aggregate with leukocytes, including lymphocytes, monocytes, and neutrophils, to immobilize pathogens and prevent viral dissemination. Despite their host protective role, platelets have also been shown to be associated with various pathophysiological processes. In this review, we will summarize platelet and HIV interactions during infection. We will also highlight and discuss platelet and platelet-derived mediators, how they interact with immune cells, and the multifaceted responsibilities of platelets in HIV infection. Furthermore, we will give an overview of non-AIDS comorbidities linked to platelet dysfunction and the impact of antiretroviral therapy on platelet function.

Venous thromboembolism in viral diseases: A comprehensive literature review

Venous thromboembolism (VTE) is known to be a common respiratory and/or cardiovascular complication in hospitalized patients with viral infections. Numerous studies have proven human immunodeficiency virus infection to be a prothrombotic condition. An elevated VTE risk has been observed in critically ill H1N1 influenza patients. VTE risk is remarkably higher in patients infected with the Hepatitis C virus in contrast to uninfected subjects. The elevation of D-dimer levels supported the association between Chikungunya and the Zika virus and the rise of clinical VTE risk. Varicella-zoster virus is a risk factor for both cellulitis and the consequent invasive bacterial disease which may take part in thrombotic initiation. Eventually, hospitalized patients infected with the coronavirus disease of 2019 (COVID-19), the cause of the ongoing worldwide pandemic, could mainly suffer from an anomalous risk of coagulation activation with enhanced venous thrombosis events and poor quality clinical course. Although the risk of VTE in nonhospitalized COVID-19 patients is not known yet, there are a large number of guidelines and studies on thromboprophylaxis administration for COVID-19 cases. This study aims to take a detailed look at the effect of viral diseases on VTE, the epidemiology of VTE in viral diseases, and the diagnosis and treatment of VTE.

Recommendations for the Management of Drug-Drug Interactions Between the COVID-19 Antiviral Nirmatrelvir/Ritonavir (Paxlovid) and Comedications

The coronavirus disease 2019 (COVID-19) antiviral nirmatrelvir/ritonavir (Paxlovid) has been granted authorization or approval in several countries for the treatment of patients with mild to moderate COVID-19 at high risk of progression to severe disease and with no requirement for supplemental oxygen. Nirmatrelvir/ritonavir will be primarily administered outside the hospital setting as a 5-day course oral treatment. The ritonavir component boosts plasma concentrations of nirmatrelvir through the potent and rapid inhibition of the key drug-metabolizing enzyme cytochrome P450 (CYP) 3A4. Thus nirmatrelvir/ritonavir, even given as a short treatment course, has a high potential to cause harm from drug-drug interactions (DDIs) with other drugs metabolized through this pathway. Options for mitigating risk from DDIs with nirmatrelvir/ritonavir are limited due to the clinical illness, the short window for intervention, and the related difficulty of implementing clinical monitoring or dosage adjustment of the comedication. Pragmatic options are largely confined to preemptive or symptom-driven pausing of the comedication or managing any additional risk through counseling. This review summarizes the effects of ritonavir on drug disposition (i.e., metabolizing enzymes and transporters) and discusses factors determining the likelihood of having a clinically significant DDI. Furthermore, it provides a comprehensive list of comedications likely to be used in COVID-19 patients which are categorized according to their potential DDI risk with nirmatrelvir/ritonavir. It also discusses recommendations for the management of DDIs which balance the risk of harm from DDIs with a short course of ritonavir, against unnecessary denial of nirmatrelvir/ritonavir treatment.

Cardiovascular Drug Interactions With Nirmatrelvir/Ritonavir in Patients With COVID-19: JACC Review Topic of the Week

Nirmatrelvir-ritonavir (NMVr) is used to treat symptomatic, nonhospitalized patients with coronavirus disease-2019 (COVID-19) who are at high risk of progression to severe disease. Patients with cardiovascular risk factors and cardiovascular disease are at a high risk of developing adverse events from COVID-19 and as a result have a higher likelihood of receiving NMVr. Ritonavir, the pharmaceutical enhancer used in NMVr, is an inhibitor of the enzymes of CYP450 pathway, particularly CYP3A4 and to a lesser degree CYP2D6, and affects the P-glycoprotein pump. Co-administration of NMVr with medications commonly used to manage cardiovascular conditions can potentially cause significant drug-drug interactions and may lead to severe adverse effects. It is crucial to be aware of such interactions and take appropriate measures to avoid them. In this review, we discuss potential drug-drug interactions between NMVr and commonly used cardiovascular medications based on their pharmacokinetics and pharmacodynamic properties.

Dilemmas in the Choice of Adequate Therapeutic Treatment in Patients with Acute Pulmonary Embolism—From Modern Recommendations to Clinical Application

Pulmonary thromboembolism is a very common cardiovascular disease, with a high mortality rate. Despite the clear guidelines, this disease still represents a great challenge both in diagnosis and treatment. The heterogeneous clinical picture, often without pathognomonic signs and symptoms, represents a huge differential diagnostic problem even for experienced doctors. The decisions surrounding this therapeutic regimen also represent a major dilemma in the group of patients who are hemodynamically stable at initial presentation and have signs of right ventricular (RV) dysfunction proven by echocardiography and positive biomarker values (pulmonary embolism of intermediate–high risk). Studies have shown conflicting results about the benefit of using fibrinolytic therapy in this group of patients until hemodynamic decompensation, due to the risk of major bleeding. The latest recommendations give preference to new oral anticoagulants (NOACs) compared to vitamin K antagonists (VKA), except for certain categories of patients (patients with antiphospholipid syndrome, mechanical valves, pregnancy). When using oral anticoagulant therapy, special attention should be paid to drug–drug interactions, which can lead to many complications, even to the death of the patient. Special population groups such as pregnant women, obese patients, patients with antiphospholipid syndrome and the incidence of cancer represent a great therapeutic challenge in the application of anticoagulant therapy. In these patients, not only must the effectiveness of the drugs be taken into account, but great attention must be paid to their safety and possible side effects, which is why a multidisciplinary approach is emphasized in order to provide the best therapeutic option.

Pharmacotherapeutic agents for the management of COVID-19 patients with preexisting cardiovascular disease

INTRODUCTION

The coronavirus disease 2019 (COVID-19) pandemic is the largest public health challenge of the twenty-first century. While COVID-19 primarily affects the respiratory system, manifesting as interstitial pneumonitis and severe acute respiratory distress syndrome (ARDS), it also has implications for the cardiovascular system. Moreover, those admitted to hospital with severe COVID-19 are more likely to have cardiovascular comorbidities such as hypertension and diabetes mellitus. The underlying pathophysiology of why COVID-19 onset can further decline cardiac pathologies as well as trigger acute onset of new cardiac complications is not yet well understood.

AREAS COVERED

In this review, the authors extensively review literature focused on the current understanding and approaches of managing patients who have underlying cardiovascular diseases and concomitant COVID-19 infection. Furthermore, the authors explore the possible cardiovascular implications of the suggested COVID-19 therapeutic agents that are used to treat this lethal disease.

EXPERT OPINION

Current evidence is evolving around the many trialed pharmacotherapeutic considerations for the management of coronavirus disease 2019 (COVID-19) in patients with cardiovascular disease. While we await such data, clinicians should advocate for careful consideration of all concomitant medications for those presenting with COVID-19 on a patient-by-patient basis.

Analysis of Direct Oral Anticoagulant Therapy With Concomitant Use of Interacting Antiretroviral Agents

Background: A theoretical interaction exists between human immunodeficiency virus (HIV) antiretroviral (ARV) agents and direct oral anticoagulants (DOACs), although the clinical significance is unclear. Objective: This study aimed to assess characteristics, prescribing patterns, and outcomes associated with concomitant therapy. Methods: A single-center, retrospective review was performed on patients older than 18 years prescribed a DOAC for any indication with concurrent interacting ARV(s) from June 2016 through June 2019. The primary endpoint was to assess prescribing and population characteristics. Secondary endpoints were to evaluate safety outcomes, DOAC level monitoring, readmissions, outpatient follow-up, and DOAC modification interventions. Results: Thirty-six patients (72 hospital admissions) were identified. The most common DOAC was apixaban (83.3%) and ARV was ritonavir (50%). Of the 72 encounters, 26 (36.1%) DOACs were dosed appropriately per guideline recommendations. Twenty pharmacy interventions for therapy modification were recognized. Eleven (30.6%) patients experienced bleeding and 2 (5.6%) thrombosis. Of the adverse events, all patients had renal impairment. Conclusions: As DOAC utilization grows, increasing use in HIV could be expected. More frequent adjustment or avoidance is recommended per guidelines. Our data suggest the majority of patients receive CYP3A4-inhibiting regimens. Caution should be employed with renal insufficiencies. Further studies are warranted to assess safety and efficacy within this population.

ANMCO POSITION PAPER: cardio-oncology in the COVID era (CO and CO)

The COVID-19 pandemic and its impact on patients with cancer and cardiovascular disease have confirmed the particular vulnerability of these populations. Indeed, not only a higher risk of contracting the infection has been reported but also an increased occurrence of a more severe course and unfavourable outcome. Beyond the direct consequences of COVID-19 infection, the pandemic has an enormous impact on global health systems. Screening programmes and non-urgent tests have been postponed; clinical trials have suffered a setback. Similarly, in the area of cardiology care, a significant decline in STEMI accesses and an increase in cases of late presenting heart attacks with increased mortality and complication rates have been reported. Health care systems must therefore get ready to tackle the 'rebound effect' that will likely show a relative increase in the short- and medium-term incidence of diseases such as heart failure, myocardial infarction, arrhythmias, and cardio- and cerebrovascular complications. Scientific societies are taking action to provide general guidance and recommendations aimed at mitigating the unfavourable outcomes of this pandemic emergency. Cardio-oncology, as an emerging discipline, is more flexible in modulating care pathways and represents a beacon of innovation in the development of multi-specialty patient management. In the era of the COVID-19 pandemic, cardio-oncology has rapidly modified its clinical care pathways and implemented flexible monitoring protocols that include targeted use of cardiac imaging, increased use of biomarkers, and telemedicine systems. The goal of these strategic adjustments is to minimize the risk of infection for providers and patients while maintaining standards of care for the treatment of oncologic and cardiovascular diseases. The aim of this document is to evaluate the impact of the pandemic on the management of cardio-oncologic patients with the-state-of-the-art knowledge about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease (COVID-19) in order to optimize medical strategies during and after the pandemic.

Direct oral anticoagulants versus warfarin in people living with human immunodeficiency virus

Human immunodeficiency virus (HIV) is associated with increased rates of cardiovascular disease and vascular events, and people living with HIV (PLWH) may often have indications for therapeutic anticoagulation. However, the ideal anticoagulant in PLWH remains unknown. This retrospective cohort evaluated the tolerability and effectiveness of oral anticoagulants in PLWH. The primary outcome was tolerability, defined as a composite of bleeding and/or discontinuation rates. The secondary outcomes included recurrent thromboembolism, bleeding, and discontinuations, independently. There were 92 patients included for analysis, 48 in the direct oral anticoagulant (DOAC) arm and 44 in the warfarin arm. There were 35 (38%) PLWH that did not tolerate oral anticoagulation therapy in the total cohort. Among these, 19 received a DOAC and 16 received warfarin. There were 16 (17%) PLWH that experienced a bleeding event: six in the DOAC arm and 10 in the warfarin arm. There were 15 (16%) PLWH that experienced recurrent thromboembolism, with similar rates between DOAC versus warfarin (10, 21% vs 5, 11%, respectively; p = 0.11). The most commonly prescribed HIV regimens were protease inhibitor and integrase inhibitor-based regimens. Overall, anticoagulation-related outcomes with either a DOAC or warfarin were poor in our cohort of PLWH, with high rates of bleeding, discontinuations, and recurrent thromboembolism. Further studies are necessary to validate and assess reasons for poor tolerability.

Drug interactions with apixaban: A systematic review of the literature and an analysis of VigiBase, the World Health Organization database of spontaneous safety reports

Apixaban, a direct oral anticoagulant, has emerged over the past few years because it is considered to have a low risk of drug‐drug interactions compared to vitamin K antagonists. To better characterize these interactions, we systematically reviewed studies evaluating the drug‐drug interactions involving apixaban and analyzed the drug‐drug interactions resulting in an adverse drug reaction reported in case reports and VigiBase. We systematically searched Medline, Embase, and Google Scholar up to 20 August 2018 for articles that investigated the occurrence of an adverse drug reaction due to a potential drug interacting with apixaban. Data from VigiBase came from case reports retrieved up to the 2 January 2018, where identification of potential interactions is performed in terms of two drugs, one adverse drug reaction triplet and potential signal detection using Omega, a three‐way measure of disproportionality. We identified 15 studies and 10 case reports. Studies showed significant variations in the area under the curve for apixaban and case reports highlighted an increased risk of hemorrhage or thromboembolic events due to a drug‐drug interaction. From VigiBase, a total of 1617 two drugs and one adverse drug reaction triplet were analyzed. The most reported triplet were apixaban—aspirin—gastrointestinal hemorrhage. Sixty‐seven percent of the drug‐drug interactions reported in VigiBase were not described or understood. In the remaining 34%, the majority were pharmacodynamic drug‐drug interactions. These data suggest that apixaban has significant potential for drug‐drug interactions, either with CYP3A/P‐gp modulators or with drugs that may impair hemostasis. The most described adverse drug reactions were adverse drug reactions related to hemorrhage or thrombosis, mostly through pharmacodynamic interactions. Pharmacokinetic drug‐drug interactions seem to be poorly detected.

Traveling for heart transplantation and returning with COVID-19: a logistical, clinical, and pharmacotherapeutic challenge from the Middle East

Heart transplantation (HT) has become a standard option for patients with end-stage heart failure (HF). However, the scarcity of donor availability remains a major hurdle for receiving this novel therapy, especially in the context of the rapidly spreading severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; COVID-19) pandemic. We report the case of a patient in the United Arab Emirates (UAE) with advanced HF who was glucose-6-phosphate dehydrogenase deficient and had a history of type 2 diabetes mellitus with diabetic retinopathy and nephropathy, chronic kidney disease stage II, and hyperlipidemia. He was referred for HT abroad and was subsequently caught in the midst of the COVID-19 pandemic in New York, the US state most affected by the crisis at the time. Despite limited experience with favipiravir, we judged it to be the most appropriate agent with this patient’s complex history given the lower risk for QT prolongation, no need for renal-dose adjustment, and no reported drug–drug interactions. Given the limited clinical experience with this agent, particularly for our patient, we decided to adopt strategies to mitigate and monitor the potential for QT prolongation. We outline the logistical, clinical, and pharmacological challenges that the poly-morbid patient and our HT program in the Middle-East faced under those novel circumstances.

Venous thromboembolism in people living with HIV infection (PWH)

The risk of venous thromboembolism (VTE) and of recurrent VTE remain elevated in people living with HIV compared to controls still with contemporary antiretroviral therapy (ART). The pathophysiology of VTE in HIV is multi factorial and includes an interplay among traditional risk factors, HIV-specific factors, behavioral factors, exposure to ART and other therapies, coinfections, and co-morbidities.

Clopidogrel drug interactions: a review of the evidence and clinical implications

INTRODUCTION

Patients with cardiovascular disease are commonly affected by a number of comorbidities leading to a high prevalence of polypharmacy. Polypharmacy increases the probability of drug-drug interactions (DDIs). Amongst these, DDIs involving clopidogrel, the most commonly utilized platelet P2Y₁₂ inhibitor, is a topic of potential clinical concern.

AREAS COVERED

This article reviews DDIs between clopidogrel and drugs which are widely used in clinical practice. In particular, drugs shown to interfere with the pharmacodynamic and pharmacokinetic effects of clopidogrel and the clinical implications of these findings are reviewed. These drugs include inhibitors of gastric acid secretion, statins, calcium channel blockers, antidiabetic agents, and antimicrobial agents. For the references, we searched PubMed, EMBASE, or the Cochrane Library.

EXPERT OPINION

Clopidogrel-drug interactions are common. Most of these DDIs are limited to laboratory findings showing an impact on clopidogrel-induced antiplatelet effects. While variability in clopidogrel-induced antiplatelet effects is known to affect clinical outcomes, with high platelet reactivity being associated with thrombotic complications among patients undergoing coronary stenting, most studies assessing the clinical implications of clopidogrel-drug interactions have not shown to significantly affect outcomes. However, awareness of these DDIs remains important for optimizing the selection of concomitant therapies.

Cardiovascular Considerations in Treating Patients With Coronavirus Disease 2019 (COVID-19)

A novel betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread rapidly across the globe since December 2019. Coronavirus disease 2019 (COVID-19) has a significantly higher mortality rate than seasonal influenza and has disproportionately affected older adults, especially those with cardiovascular disease and related risk factors. Adverse cardiovascular sequelae, such as myocarditis, acute myocardial infarction, and heart failure, have been reported in patients with COVID-19. No established treatment is currently available; however, several therapies, including remdesivir, hydroxychloroquine and chloroquine, and interleukin (IL)-6 inhibitors, are being used off-label and evaluated in ongoing clinical trials. Considering these therapies are not familiar to cardiovascular clinicians managing these patients, this review describes the pharmacology of these therapies in the context of their use in patients with cardiovascular-related conditions.

Managing ACS during COVID-19 infection: Do not follow the traditional route

COVID-19 pandemic is creating havoc in the world. It is also spreading in India creating a massive healthcare problem. Few major hospitals were closed down because of the spread among healthcare personnel. Management of several commonly occurring diseases needed modifications to a lesser or greater extent because of this pandemic. Management of acute coronary syndrome (ACS) also requires certain modifications. In this opinion paper an attempt has been made to give an outline of ACS management in this changed scenario.

Prevention of stroke in people living with HIV

In the era of effective antiretroviral therapy (ART), HIV has become a manageable disease marked by an elevated risk of non-AIDS-related comorbidities, including stroke. Rates of stroke are higher in people living with HIV (PLWH) compared with the general population. Elevated stroke risk may be attributable to traditional risk factors, HIV-associated chronic inflammation and immune dysregulation, and possible adverse effects of long-standing ART use. Tailoring stroke prevention strategies for PLWH requires knowledge of how stroke pathogenesis may differ from non-HIV-associated stroke, knowledge of long-term stroke outcomes in HIV, and accurate stroke risk assessment tools. As a result, the approach to primary and secondary stroke prevention in PLWH relies heavily on guidelines developed for the general population, with an emphasis on optimization of traditional vascular risk factors and early initiation of ART. This review summarizes existing evidence on HIV-associated stroke mechanisms and considerations for stroke prevention for PLWH.

Stroke and Systemic Thromboembolism Prevention in People Living With Human Immunodeficiency Virus With Atrial Fibrillation: A Review of Its Implications for Clinical Practice

In the last few decades, types of diseases affecting people living with human immunodeficiency virus (PLHIV) have shifted as the population ages, with cardiovascular disease becoming a leading cause of death in this population. Atrial fibrillation (AF) is an increasingly common arrhythmia both in the general population and in PLHIV, with an estimated prevalence of 2% to 3% among PLHIV. Prevention of stroke and systemic thromboembolism (SSE) with antithrombotic therapy is a cornerstone of AF treatment and substantially decreases AF-related morbidity and mortality. Although updated guidelines extensively discuss this issue, they do not address the peculiarities of PLHIV. The role of human immunodeficiency virus (HIV) infection as an independent factor for SSE in individuals with AF and whether the presence of HIV should alter the threshold for SSE thromboprophylaxis are unknown. Nevertheless, a growing body of evidence describes the increasing burden of comorbidities such as hypertension and stroke in PLHIV, which predispose them to AF and SSE. In the absence of HIV-specific AF guidelines, PLHIV with AF should be comprehensively assessed for their risk of SSE and bleeding using commonly available scores despite them having been primarily validated in the non-HIV population. Both vitamin K antagonists and direct oral anticoagulants can be used in PLHIV. Addressing HIV-related comorbidities and potential drug-drug interactions with antiretrovirals is crucial to prevent SSE and reduce adverse reactions of oral anticoagulants. This review summarizes the current guidelines for SSE prevention in patients with AF and describes key considerations for their implementation among PLHIV receiving antiretroviral therapy.

In-hospital and long-term outcomes of HIV-positive patients undergoing PCI according to kind of stent: a meta-analysis

BACKGROUND

Pathogenesis of cardiovascular disease in HIV-positive patients is related to the interaction between traditional and HIV-specific factors. Limited data are available regarding the prognosis of HIV-positive patients undergoing percutaneous coronary intervention (PCI).

METHODS

All observational studies evaluating the prognosis of HIV-positive patients treated with PCI were included. In-hospital and long-term major adverse cardiac events (MACE) [composite endpoint of all-cause death or myocardial infarction (MI)] were the primary endpoints, whereas in-hospital and long-term all-cause death, cardiovascular death, MI, stent thrombosis, target vessel revascularization (TVR), target lesion revascularization (TLR), and bleeding complications were the secondary ones.

FINDINGS

In all, 1243 patients in nine studies were included, with a mean age of 54 years. Among them, 12% were female and 91% were admitted for acute coronary syndromes. In-hospital MACE occurred in 6.0% (5.4-6.6), death in 4.2% (2.6-5.9), and MI in 1.3% (0-2.8), whereas major bleeding occurred in 2.0% (1.7-2.3) of the patients. After 2 years (1.6-3.1), long-term MACE occurred in 17.4% (11.9-22.3), all-cause death in 8.7% (3.2-14.2), and MI in 7.8% (5.5-10.1) of the patients, whereas stent thrombosis and TVR in 3.4% (1.5-5.3) and 10.5% (7.5-13.4), respectively. In patients treated with drug-eluting stents (DES), the rate of long-term MACE was 22.3% (10.1-34.4), with an incidence of 4.9% (0.0-11.4) of MI and 5.7% (2.3-13.7, all 95% confidence intervals of TLR.

INTERPRETATION

HIV-positive patients have a high risk of in-hospital and long-term MACE after PCI, partially reduced by the use of DES. Further studies on the risk of recurrent ischemic events with current generation stents are needed, to offer a tailored therapy in this high-risk population.

Statins and aspirin in the prevention of cardiovascular disease among HIV-positive patients between controversies and unmet needs: review of the literature and suggestions for a friendly use

BACKGROUND

As in non-infected subjects, statins and aspirin have a pivotal preventive role in reducing the cardiovascular related morbidity and mortality in HIV infected patients. The persistence of immune activation in these subjects, could contribute to accelerate atherosclerosis, therefore, these treatments that reduce inflammation could provide additional cardiovascular protection. However the current guidelines for the use of these drugs in general population are dissimilar, with important differences between American and European ones. Aim of the present position paper is to provide recommendations aimed to overcome the actual differences and limitations among the current ones and to adapt them to the needs of HIV infected patients.

RESULTS

We propose to adopt the new ACC/AHA guidelines, simple to use and cost effective, to use the ASCVD score that seems to estimate more accurately the cardiovascular risk among these patients. We suggest to start statin therapy in all patients with a calculated 10-year risk of a cardiovascular event of 10% or greater. Rosuvastatin and atorvastatin should be preferred. LDL-C target may be adopted. Aspirin should be always associated with a statin, in secondary prevention, while in primary prevention it should be reserved only to patients with ≥ 20% 10-year risk particularly adherent to treatments, and with low risk of bleeding. We suggest to start with a dose of 100 mg/day. Finally, management of antiplatelet agents or novel oral anticoagulants may include selecting antiretrovirals with a lower potential for drug interactions or choosing agents least likely to interact with antiretrovirals.

CONCLUSIONS

As demonstrated in surveys, HIV physicians are generally highly committed regarding CVD and autonomous in prescribing statins and ASA. Consequently, in the light of the previously discussed discrepancies among the different guidelines and of the incomplete indications regarding HIV-positive persons, the present suggestions could overcome the actual differences and limitations among the current ones.

Ritonavir- or cobicistat-boosted antiretroviral therapy and direct oral anticoagulants: A case for apixaban

The potential for drug-drug interactions (DDIs) between direct oral anticoagulants and antiretroviral therapy (ART) is vast. Ritonavir and cobicistat are used as pharmacokinetic enhancers with either concurrent protease inhibitors or the integrase strand transfer inhibitor, elvitegravir, to optimize therapeutic concentrations by cytochrome P450 (CYP) inhibition. To date, only rivaroxaban and dabigatran have reported cases of use with ritonavir-boosted ART. Apixaban is metabolized similarly to rivaroxaban, but offers a dose reduction in the case of major DDIs. We report the successful use of reduced-dose apixaban to treat and prevent thromboembolic complications in six persons living with human immunodeficiency virus (HIV) on ritonavir- or cobicistat-boosted ART. This case series and available literature support the use of apixaban or dabigatran, depending on the boosted ART regimen.

Use of dabigatran with antiretrovirals

OBJECTIVES

Theoretical and untested interactions between antiretrovirals and direct-acting oral anticoagulants have limited the use of this new class of anticoagulant in people with HIV infection. This case series, the first of its kind, reports on the successful concurrent use of the direct-acting oral anticoagulant dabigatran and antiretroviral therapy.

METHODS

This series involved 14 patients requiring anticoagulation for management of atrial fibrillation, who were either unable or unwilling to take warfarin, and who were receiving concurrent treatment for HIV infection. Participants were treated with dabigatran with dose monitoring to establish the safety and efficacy of concurrent use with antiretrovirals. All were commenced on 110 mg twice daily, increased to 150 mg twice daily if the trough level was < 69.3 ng/mL.

RESULTS

In the 14 patients treated with dabigatran and antiretrovirals, there were no thromboembolic or bleeding complications. Dabigatran treatment was discontinued in one patient because of undetectable dabigatran levels despite dose escalation. Dabigatran levels fell within the fivefold variance seen in the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) study at a dose of either 110 or 150 mg twice daily.

CONCLUSIONS

This case series represents the largest published population to date successfully receiving antiretroviral and direct-acting oral anticoagulant therapy. Given the significant health care burden faced by people living with HIV, the availability of safe anticoagulant therapy without the requirement for monitoring is an important option in this patient population.

Cardiovascular disease burden among human immunodeficiency virus-infected individuals

Human Immunodeficiency Virus (HIV) infection affects 36.7 million people worldwide, it accounted for 1.1 million deaths in 2015. The advent of combined antiretroviral therapy (cART) has been associated with a decrease in HIV-related morbidity and mortality. However, there are increasing concerns about long-lasting effects of chronic inflammation and immune activation, leading to premature aging and HIV-related mortality. Cardiovascular diseases, especially coronary artery disease, are among the leading causes of death in HIV-infected patients, accounting for up to 15% of total deaths in high income countries. Furthermore, as cART availability expands to low-income countries, the burden of cardiovascular related mortality is likely to rise. Hence, over the next decade HIV-associated cardiovascular disease burden is expected to increase globally. In this review, we summarize our understanding of the pathogenesis and risk factors associated with HIV infection and cardiovascular disease, in particular coronary artery disease.

Atrial fibrillation and human immunodeficiency virus type-1 infection: a systematic review. Implications for anticoagulant and antiarrhythmic therapy

The prevalence and incidence of atrial fibrillation/flutter (AF/AFL) in patients with human immunodeficiency virus type-1 (HIV-1) infection have been poorly investigated. We performed a systematic review using PubMed and Cochrane Database of Systematic Reviews, and screening of references, searching for clinical studies reporting on the association between HIV-1 infection and AF/AFL. We also summarized the main interactions of antiretroviral agents with antithrombotic and antiarrhythmic drugs. We found a prevalence of AF/AFL ranging from 2.0% to 5.13% in patients with HIV-1, with an incidence rate of 3.6/1000 person-years. Low CD4+ count (<200-250 cells ml^-1 ) and high viral load were predictors of AF/AFL. Regarding drugs interactions, nucleoside reverse transcriptase inhibitors, integrase inhibitor and maraviroc have the lowest interactions with oral anticoagulants. Among anticoagulants, dabigatran presents the most favourable profile. Most of antiarrhythmic drugs interact with protease inhibitors, with beta blockers and diltiazem having fewer interactions. The few studies available suggest a non-negligible prevalence of AF/AFL in patients with HIV-1 infection. Awareness of potential interactions with anticoagulation and antiarrhythmic drugs is needed to offer optimal management in this population.

Coronary Artery Disease Manifestations in HIV: What, How, and Why

Understanding why persons with human immunodeficiency virus (HIV) have accelerated atherosclerosis and its sequelae, including coronary artery disease (CAD) and myocardial infarction, is necessary to provide appropriate care to a large and aging population with HIV. In this review, we delineate the diverse pathophysiologies underlying HIV-associated CAD and discuss how these are implicated in the clinical manifestations of CAD among persons with HIV. Several factors contribute to HIV-associated CAD, with chronic inflammation and immune activation likely representing the primary drivers. Increased monocyte activation, inflammation, and hyperlipidemia present in chronic HIV infection also mirror the pathophysiology of plaque rupture. Furthermore, mechanisms central to plaque erosion, such as activation of toll-like receptor 2 and formation of neutrophil extracellular traps, are also abundant in HIV. In addition to inflammation and immune activation in general, persons with HIV have a higher prevalence than uninfected persons of traditional cardiovascular risk factors, including dyslipidemia, hypertension, insulin resistance, and tobacco use. Antiretroviral therapies, although clearly necessary for HIV treatment and survival, have had varied effects on CAD, but newer generation regimens have reduced cardiovascular toxicities. From a clinical standpoint, this mix of risk factors is implicated in earlier CAD among persons with HIV than uninfected persons; whether the distribution and underlying plaque content of CAD for persons with HIV differs considerably from uninfected persons has not been definitively studied. Furthermore, the role of cardiovascular risk estimators in HIV remains unclear, as does the role of traditional and emerging therapies; no trials of CAD therapies powered to detect clinical events have been completed among persons with HIV.

Pharmacokinetic drug interactions of the non-vitamin K antagonist oral anticoagulants (NOACs)

The use of warfarin, the most commonly prescribed oral anticoagulant, is being questioned by clinicians worldwide due to warfarin several limitations (a limited therapeutic window and significant variability in dose-response among individuals, in addition to a potential for drug-drug interactions). Therefore, the need for non-vitamin K antagonist oral anticoagulants (NOACs) with a rapid onset of antithrombotic effects and a predictable pharmacokinetic (PK) and pharmacodynamic (PD) profile led to the approval of five new drugs: the direct factor Xa (F-Xa) inhibitors rivaroxaban, apixaban, edoxaban and betrixaban (newly approved by FDA) and the direct thrombin (factor-IIa) inhibitor dabigatran etexilate. The advantages of NOACs over warfarin are a fixed-dosage, the absence of the need for drug monitoring for changes in anti-coagulation and fewer clinically significant PK and PD drug-drug interactions. NOACs exposure will likely be increased by the administration of strong P-glycoprotein (P-gp) and cytochrome P450 (CYP) 3A4-inhibitors and may increase the risk of bleeds. On the contrary, P-gp inducers could significantly decrease the NOACs plasma concentration with an associated reduction in their anticoagulant effects. This manuscript gives an overview of NOACs PK profiles and their drug-drug interactions potential. This is meant to be of help to physicians in choosing the best therapeutic approach for their patients.

Use of direct oral anticoagulants for treatment of atrial fibrillation in patients with HIV: a review

PURPOSE OF REVIEW

Atrial fibrillation is increasingly common in the ageing population. Patients with atrial fibrillation and HIV have a higher stroke risk, with guidelines recommending anticoagulation in the majority. Whilst anticoagulation options have diversified in the last decade for the general population, there is limited evidence for the safety and efficacy of these medications when used concurrently with antiretroviral therapy. We review the potential for patients with HIV on antiretroviral therapy to have direct-acting oral anticoagulations (DOACs).

RECENT FINDINGS

Several case reports have been published in the past 5 years, as well as theoretical analyses of anticipated drug interactions, which provide a starting point to guide use of DOACs with antiretroviral medications.

SUMMARY

Caution is needed when prescribing DOACs in patients with atrial fibrillation and HIV due to potential drug interactions. Studies are lacking and current advice is based on case reports, expert opinion and knowledge of theoretical interactions.

The Significance of Drug-Drug and Drug-Food Interactions of Oral Anticoagulation

Vitamin K antagonists (VKAs) such as warfarin are the most commonly prescribed oral anticoagulants worldwide. However, factors affecting the pharmacokinetics of VKAs, such as food and drugs, can cause deviations from their narrow therapeutic window, increasing the bleeding or thrombosis risk and complicating their long-term use. The use of direct oral anticoagulants (DOACs) offers a safer and more convenient alternative to VKAs. However, it is important to be aware that plasma levels of DOACs are affected by drugs that alter the cell efflux transporter P-glycoprotein and/or cytochrome P450. In addition to these pharmacokinetic-based interactions, DOACs have the potential for pharmacodynamic interaction with antiplatelet agents and non-steroidal anti-inflammatory drugs. This is an important consideration in patient groups already at high risk of bleeding, such as patients with renal impairment.

A Therapeutic Perspective of Living with Human Immunodeficiency Virus/AIDS in 2017

Patients with human immunodeficiency virus (HIV)/AIDS live a far different life today compared with those who were infected in the 1980s and 1990s. Antiretroviral therapy has evolved from a once poorly tolerated, heavy pill burden to the availability of many once-daily single-tablet regimens. The improvements in therapy have necessitated the need to be cognizant of comorbidities as well as drug-drug interactions. Despite the tremendous advances in therapy, newer therapies are in the pipeline and continue to emerge, making care for patients burdened by HIV perhaps easier than it has ever been.

A review of drug-drug interactions in older HIV-infected patients

INTRODUCTION

The number of older HIV-infected people is growing due to increasing life expectancies resulting from the use of antiretroviral therapy (ART). Both HIV and aging increase the risk of other comorbidities, such as cardiovascular disease, osteoporosis, and some malignancies, leading to greater challenges in managing HIV with other conditions. This results in complex medication regimens with the potential for significant drug-drug interactions and increased morbidity and mortality. Area covered: We review the metabolic pathways of ART and other medications used to treat medical co-morbidities, highlight potential areas of concern for drug-drug interactions, and where feasible, suggest alternative approaches for treating these conditions as suggested from national guidelines or articles published in the English language. Expert commentary: There is limited evidence-based data on ART drug interactions, pharmacokinetics and pharmacodynamics in the older HIV-infected population. Choosing and maintaining effective ART regimens for older adults requires consideration of side effect profile, individual comorbidities, interactions with concurrent prescriptions and non-prescription medications and supplements, dietary patterns with respect to dosing, pill burden and ease of dosing, cost and affordability, patient preferences, social situation, and ART resistance history. Practitioners must remain vigilant for potential drug interactions and intervene when there is a potential for harm.

Coronary revascularization for acute myocardial infarction in the HIV population

OBJECTIVE

To analyze trends in management and outcomes of patients infected with the human immunodeficiency virus (HIV) undergoing percutaneous coronary intervention (PCI) for an acute myocardial infarction (AMI) in the United States.

BACKGROUND

Infection with HIV is an independent risk factor for accelerated atherosclerosis associated with higher rates of AMI. Current trends and outcomes of HIV-infected individuals presenting with AMI in the United States remain unknown.

METHODS

Using the Healthcare Cost and Utilization Project National Inpatient Sample database we identified HIV-infected individuals who underwent PCI for an AMI from 2002 to 2013. Multivariable logistic regression and propensity-score matching were performed to analyze outcomes.

RESULTS

We identified a total of 59 194 patients of which 7841 underwent PCI during index hospitalization (13.3%). Most patients were men (71%), ≥50 years of age (82%), and white (74%). ST-elevation myocardial infarction was present in 21% of cases. Charlson comorbidity index (CCI) was 5.67 ± 0.4. Predictors of post-procedural complications included female sex, black race, higher CCI, and placement of a bare metal stent, whereas predictors of mortality included occurrence of a complication, ST-elevation myocardial infarction, age ≥70 years, and higher CCI. Conversely, placement of a drug-eluting stent was associated with a reduced risk of complications and mortality. After propensity-score matching, HIV-infected individuals were less likely to undergo PCI and receive a drug-eluting stent, while having longer length of stay, higher hospitalization costs, and higher in-hospital mortality when compared to non-infected individuals.

CONCLUSION

Significant disparities continue to affect HIV-infected individuals undergoing PCI for AMI in the United States.

HIV and Nonischemic Heart Disease

Human immunodeficiency virus (HIV)-associated heart disease encompasses a broad spectrum of diseases. HIV infection may involve the pericardium, myocardium, coronary arteries, pulmonary vasculature, and valves, as well as the systemic vasculature. Access to combination antiretroviral therapy, as well as health resources, has had a significant influence on the prevalence and severity of the effects on each cardiac structure. Investigations over the recent past have improved our understanding of the epidemiology and pathophysiology of HIV-associated cardiovascular disease. This review will focus on our current understanding of pathogenesis and risk factors associated with HIV infection and heart disease, and it will discuss relevant advances in diagnosis and management of these conditions.

The challenge of polypharmacy in an aging population and implications for future antiretroviral therapy development

: It is estimated that by 2030 nearly three-quarters of persons living with HIV will be 50 years and older. The aging HIV population presents a new clinical concern for HIV providers: adverse effects from polypharmacy. An aging population means more comorbidities and potentially more drug-drug interactions for providers to manage. This review discusses major comorbidities including cardiovascular disease, anticoagulation, hypertension, diabetes mellitus and malignancy and considerations for drug-interactions with antiretrovirals.

Acute Care Management of the HIV-Infected Patient: A Report from the HIV Practice and Research Network of the American College of Clinical Pharmacy

OBJECTIVE

Patients infected with human immunodeficiency virus (HIV) admitted to the hospital have complex antiretroviral therapy (ART) regimens with an increased medication error rate upon admission. This report provides a resource for clinicians managing HIV-infected patients and ART in the inpatient setting.

METHODS

A survey of the authors was conducted to evaluate common issues that arise during an acute hospitalization for HIV-infected patients. After a group consensus, a review of the medical literature was performed to determine the supporting evidence for the following HIV-associated hospital queries: admission/discharge orders, antiretroviral hospital formularies, laboratory monitoring, altered hepatic/renal function, drug-drug interactions (DDIs), enteral administration, and therapeutic drug monitoring.

RESULTS

With any hospital admission for an HIV-infected patient, a specific set of procedures should be followed including a thorough admission medication history and communication with the ambulatory HIV provider to avoid omissions or substitutions in the ART regimen. DDIs are common and should be reviewed at all transitions of care during the hospital admission. ART may be continued if enteral nutrition with a feeding tube is deemed necessary, but the entire regimen should be discontinued if no oral access is available for a prolonged period. Therapeutic drug monitoring is not generally recommended but, if available, should be considered in unique clinical scenarios where antiretroviral pharmacokinetics are difficult to predict. ART may need adjustment if hepatic or renal insufficiency ensues.

CONCLUSIONS

Treatment of hospitalized patients with HIV is highly complex. HIV-infected patients are at high risk for medication errors during various transitions of care. Baseline knowledge of the principles of antiretroviral pharmacotherapy is necessary for clinicians managing acutely ill HIV-infected patients to avoid medication errors, identify DDIs, and correctly dose medications if organ dysfunction arises. Timely ambulatory follow-up is essential to prevent readmissions and facilitate improved transitions of care.

Old and new oral anticoagulants: Food, herbal medicines and drug interactions

The most commonly prescribed oral anticoagulants worldwide are the vitamin K antagonists (VKAs) such as warfarin. Factors affecting the pharmacokinetics of VKAs are important because deviations from their narrow therapeutic window can result in bleedings due to over-anticoagulation or thrombosis because of under-anticoagulation. In addition to pharmacodynamic interactions (e.g., augmented bleeding risk for concomitant use of NSAIDs), interactions with drugs, foods, herbs, and over-the-counter medications may affect the risk/benefit ratio of VKAs. Direct oral anticoagulants (DOACs) including Factor Xa inhibitors (rivaroxaban, apixaban and edoxaban) and thrombin inhibitor (dabigatran) are poised to replace warfarin. Phase-3 studies and real-world evaluations have established that the safety profile of DOACs is superior to those of VKAs. However, some pharmacokinetic and pharmacodynamic interactions are expected. Herein we present a critical review of VKAs and DOACs with focus on their potential for interactions with drugs, foods, herbs and over-the-counter medications.

Drug-drug interactions of non-vitamin K oral anticoagulants

INTRODUCTION

The approval of non-vitamin K oral anticoagulants (NOACs) as antithrombotic alternatives to vitamin K antagonists (VKAs) has changed clinical practice. However, the efficacy and safety of the four most commonly used NOACs (dabigatran, rivaroxaban, apixaban and edoxaban) might be compromised by co-administration of other medications used for various major comorbidities. Dose adjustment of the NOACs may be needed to avert cases of concomitant medication affecting NOACs absorption, metabolism and coagulation. Areas covered: This review summarizes the current knowledge regarding drug-drug interactions of NOACs in order to guide health professionals regarding the dose modification required if the NOACs are co-administered with other medication with potential significant interactions. The data were acquired from searches of PubMed and also from the NOAC reports to the European Medicines Agency and Food and Drug Administration Agency. Expert opinion: Most of the studies in this field have been organized by pharmaceutical companies. Independent research and registries will provide more information in the near future about the drug-drug interactions of NOACs. P-glycoprotein transporter and cytochrome P450 enzyme complexes appear to be the main pathways where the most drug-drug interactions with NOACs occur.

[Predictive factors of clinically significant drug-drug interactions among regimens based on protease inhibitors, non-nucleoside reverse transcriptase inhibitors and raltegravir]

BACKGROUND AND OBJECTIVE

To determine the prevalence and types of clinically significant drug-drug interactions (CSDI) in the drug regimens of HIV-infected patients receiving antiretroviral treatment.

MATERIAL AND METHODS

DESIGN

retrospective review of database. Centre: Hospital Universitario Severo Ochoa, Infectious Unit.

PARTICIPANTS

one hundred and forty-two participants followed by one of the authors were selected from January 1985 to December 2014.

DATA COLLECTION

from their outpatient medical records we reviewed information from the last available visit of the participants, in relation to HIV infection, comorbidities, demographics and the drugs that they were receiving; both antiretroviral drugs and drugs not related to HIV infection. We defined CSDI from the information sheet and/or database on antiretroviral drug interactions of the University of Liverpool (http://www.hiv-druginteractions.org) and we developed a diagnostic tool to predict the possibility of CSDI. By multivariate logistic regression analysis and by estimating the diagnostic performance curve obtained, we identified a quick tool to predict the existence of drug interactions.

RESULTS

Of 142 patients, 39 (29.11%) had some type of CSDI and in 11.2% 2 or more interactions were detected. In only one patient the combination of drugs was contraindicated (this patient was receiving darunavir/r and quetiapine). In multivariate analyses, predictors of CSDI were regimen type (PI or NNRTI) and the use of 3 or more non-antiretroviral drugs (AUC 0.886, 95% CI 0.828 to 0.944; P=.0001). The risk was 18.55 times in those receiving NNRTI and 27,95 times in those receiving IP compared to those taking raltegravir.

CONCLUSIONS

Drug interactions, including those defined as clinically significant, are common in HIV-infected patients treated with antiretroviral drugs, and the risk is greater in IP-based regimens. Raltegravir-based prescribing, especially in patients who receive at least 3 non-HIV drugs could avoid interactions.

Novel oral anticoagulants and HIV: dabigatran use with antiretrovirals

Compatibility of novel oral anticoagulants in patients with HIV taking combined antiretroviral therapy has not been established, with no published reports of successful concurrent use. We present a case where chronic anticoagulation was indicated in a patient with treated HIV and non-valvular atrial fibrillation who refused warfarin therapy. The patient tolerated the combination, with dabigatran blood levels within the expected range at a standard dosing regimen, without evidence of bleeding or other adverse outcomes. While further research is needed to establish the role of novel oral anticoagulants in patients taking antiretrovirals, this case suggests that dabigatran may be a viable option for selected patients.

Postoperative Bleeding After Administration of a Single Dose of Rivaroxaban to a Patient Receiving Antiretroviral Therapy

A 62-year-old man was admitted to hospital for elective revision of a left total hip arthroplasty. His history was significant for human immunodeficiency virus (HIV) infection for which he was taking the following antiretroviral agents (ARVs): etravirine, ritonavir, darunavir, raltegravir and tenofovir/emtricitabine. Rivaroxaban 10 mg daily was commenced on the second postoperative day for venous thromboembolism (VTE) prophylaxis. Approximately 24 h later, the patient developed hypotension and anaemia, accompanied by thigh swelling due to bleeding at the surgical site. Fluid resuscitation was commenced with red cell transfusion. The prothrombin time (PT) was prolonged at 24.3 (10.6–15.3) s, and a rivaroxaban level taken 24 h after administration was 75 ng/mL. Rivaroxaban was ceased, the PT normalised within 24 h of stopping the drug, and the patient made an uneventful recovery. None of the other coadministered drugs are known to interact with rivaroxaban, or are likely to, based on their metabolic pathways. Rivaroxaban, a substrate for cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp), is contraindicated in patients concomitantly treated with strong inhibitors of both these systems, e.g. protease inhibitors (PIs) such as ritonavir (based on in vitro data and a pharmacokinetic study in healthy volunteers). No published data are available on the PI darunavir, a moderate inhibitor; however, concomitant use with rivaroxaban should also be avoided. A prolonged PT and a rivaroxaban trough level greater than eight times that predicted from pharmacokinetic modelling suggests that bleeding was due to increased exposure to rivaroxaban, probably due to an interaction with ritonavir and darunavir. This is supported by a Drug Interaction Probability Scale (DIPS) score of 8. An interaction between a single dose of rivaroxaban and ARVs may be clinically significant; therefore, the patient’s medication history should be extensively evaluated to identify any potential interactions.