Drug interactions and antiretroviral drug monitoring

Comorbidity and concomitant medication use in an integrase strand transfer inhibitor naïve cohort on first-line dolutegravir-based antiretroviral therapy

Introduction

people living with HIV/AIDS using antiretroviral therapy sometimes present with comorbid conditions or co-infections. This could lead to an increased risk of drug interactions due to the concomitant use of drugs. The aim of the study was to explore the overall impact of dolutegravir on such comorbidities and the effect of concomitant medication on the safety and efficacy of dolutegravir.

Methods

data was collected using a survey questionnaire and a retrospective review of medical records of a prospective study sample. Medical records were retrospectively reviewed for up to 12 months after dolutegravir initiation. Concomitantly used drugs and supplements that were identified to have a potential interaction with dolutegravir were further characterized. Descriptive and summary statistics were used to describe the data, t-tests were performed on blood glucose levels and cross-tabulations were done on some variables.

Results

of the 461 participants enrolled into the study, 172 (37.3%) and 54 (11.7%) experienced comorbidity and coinfection respectively. More than 50% of the participants used concomitant medicines. Metformin use led to increased blood glucose levels (p=0.009); participants on rifampicin (n=8) received an additional daily dose of dolutegravir. Virological outcomes in participants on sodium valproate (n=2) and St John´s wort (n=1) did not show safety concerns, whilst 3 dolutegravir discontinuations were observed in participants using supplements and antacids containing divalent cations.

Conclusion

even though dolutegravir was safe and effective in the study population, with possible drug interactions leading to treatment discontinuations in only 3(0.7%) participants, further investigation into dolutegravir-induced hyperglycemia needs investigation.

HIV and hypertension epidemiology

PURPOSE OF REVIEW

The aim of this study was to provide an overview of the burden, pathogenesis, and recent recommendations for treating hypertension among people living with HIV (PLWH). This review is relevant because of the increase in the prevalence of HIV as a chronic disease and the intersection of the increasing prevalence of hypertension.

RECENT FINDINGS

The contribution of HIV to the pathogenesis of hypertension is complex and still incompletely understood. Evidence suggests that chronic inflammation from HIV, antiretroviral treatment (ART), and comorbidities such as renal disease and insulin resistance contribute to developing hypertension in PLWH. Treatment is not distinct from guidelines for HIV-noninfected people. Nonpharmacological guidelines such as decreasing blood pressure by promoting a healthy lifestyle emphasizing exercise, weight loss, and smoking cessation are still recommended in the literature. The pharmacological management of hypertension in PLWH is similar, but special attention must be given to specific drugs with potential interaction with ART regimens. Further research is needed to investigate the pathways and effects of hypertension on HIV.

SUMMARY

There are different pathways to the pathogenesis of hypertension in PLWH. Clinicians should take it into consideration to provide more precise management of hypertension in PLWH. Further research into the subject is still required.

Readmissions among People Living with HIV Admitted for Hypertensive Emergency

OBJECTIVES

People with human immunodeficiency virus (HIV) are at an increased risk of developing cardiovascular diseases. Hypertensive emergency (HTNE), a complication of hypertension with potentially serious health implications, has high healthcare utilization. We attempted to determine the association between HIV status and risk for 30-day readmission after index hospitalization for HTNE.

METHODS

We used the Nationwide Readmissions Database to identify all of the admissions during 2010-2017 with a primary discharge diagnosis of HTNE. Admissions were stratified by HIV status and comparisons were made with the χ² test. We investigated predictors of all-cause 30-day readmission via multivariable logistic regression.

RESULTS

A total of 612,854 hospitalizations with a primary discharge diagnosis of HTNE were identified, and 4115 (0.7%) were HIV positive. There was a total of 43,937 (7.16%) 30-day readmissions, and the rate was higher in regard to positive HIV status (29.8% vs 15.0%; P < 0.001). Renal failure was the most frequent reason for HIV readmissions and the second most frequent reason for non-HIV readmissions (15.6% vs 10.3%; P < 0.001). In contrast, heart failure was the most frequent reason for non-HIV readmissions and the second most frequent reason for HIV readmissions (10.3% vs 11.9%; P = 0.234). There was a higher median cost for HIV readmissions in comparison to non-HIV readmissions ($7660 vs $7490; P < 0.001). Finally, HIV was attributed to 40.6% increased odds of readmission after adjusting for pertinent clinical and demographic factors (P < 0.001).

CONCLUSIONS

HIV-positive status is associated with an increased risk for 30-day readmission after index hospitalization for HTNE.

Safety and Tolerability of Once Daily Coformulated Bictegravir, Emtricitabine, and Tenofovir Alafenamide for Postexposure Prophylaxis After Sexual Exposure

BACKGROUND

Antiretroviral post-exposure prophylaxis (PEP) is recommended to prevent HIV infection after a high-risk exposure, but current regimens have presented challenges in tolerability, regimen completion, and potential drug-drug interactions. Because coformulated bictegravir, emtricitabine, and tenofovir alafenamide [BIC/FTC/tenofovir alafenamide (TAF)] is effective for HIV treatment, it was evaluated for use for PEP.

SETTING

Boston community health center.

METHODS

Individuals accessing PEP were enrolled in an open-label study of coformulated BIC/FTC/TAF, taken as one pill daily for 28 days. Pearson's χ2 and Fisher's exact tests were used to assess whether BIC/FTC/TAF differed with respect to side effects and regimen completion rates compared with historical PEP regimens.

RESULTS

Between August, 2018 and March, 2020, 52 individuals enrolled in the study. Most identified as cisgender gay (67.3%) or bisexual (11.5%) men, but 7.7% identified as cisgender heterosexual men and 3.8% cisgender heterosexual women. The most common regimen side effects were nausea or vomiting (15.4%), fatigue (9.6%), and diarrhea/loose stools (7.7%), which were less common than historical controls using other PEP regimens, including those containing other integrase strand transfer inhibitors. Only 1 participant discontinued the regimen because of fatigue, and all other side effects were self-limited. Almost all participants (90.4%) completed the indicated regimen, which was a higher completion rate compared with earlier PEP regimens, and none became HIV-positive.

CONCLUSIONS

BIC/FTC/TAF coformulated as a single daily pill was found to be safe, well-tolerated, and highly acceptable when used for PEP, and compared more favorably than historical PEP regimens used at an urban health center.

Corticosteroids Use and Incidence of Severe Infections in People Living with HIV Compared to a Matched Population

Background:

People living with HIV (PLWH) have been shown to have an increased risk of autoimmune diseases. Corticosteroids are the cornerstone of autoimmune diseases treatment, but their use is associated with an increased risk of infections. It is unclear how HIV status affects the risk of infection associated with corticosteroids use.

Methods:

We conducted a retrospective cohort study from 1991 to 2011, using a medico-administrative database from Quebec. Medical billing codes were used to identify PLWH, and we matched them on age, sex, and index date with up to 4 HIV-negative controls. The exposure of interest was the use of corticosteroids, defined as a systemic corticosteroid dispensation lasting at least 20 days. The outcome of interest was hospitalization for severe infection. Crude and adjusted incidence rates ratios of infection were obtained using a random effect Poisson model, and results were stratified by HIV status.

Results:

In total, 4798 PLWH were matched to 17 644 HIV-negative controls, among which 1083 (22.6%) PLWH and 1854 (10.5%) HIV-negative controls received at least one course of corticosteroid. The mean duration of corticosteroids use was 4 ± 4.4 months in PLWH and 1.6 ± 5.5 months in HIV-negative controls. The incidence rate ratio (IRR) for infections associated with corticosteroids use was 2.49[1.71–3.60] in PLWH and 1.32[0.71–2.47] in HIV-negative controls (P value for interaction 0.18). The most frequent infections were pulmonary infections (50.4%), followed by urinary tract infections (26%) and opportunistic infections (10.5%).

Conclusion:

Although our interaction term did not reach significance, the increased risk of infection associated with corticosteroids use was more pronounced in PLWH. However, further research with contemporary data is warranted to confirm if the risk associated with corticosteroids use remains high in PLWH with well-controlled HIV infection.

Study of natural product adverse events in adult HIV-infected patients in Canada

INTRODUCTION

Many individuals living with HIV use natural health products (NHPs) in an effort to decrease medication side effects and to enhance overall well-being.

METHODS

An active surveillance study of adult patients (≥ 18 years) with HIV was conducted between 2012 and 2014 to detect prescription drug and NHP use and associated adverse events (AEs) in the last month.

RESULTS

Of the 167 participants, 85 (50.9%) took prescription medications only, three (1.8%) took NHPs only, 75 (44.9%) took NHPs and prescription medications concurrently, and four (2.4%) took neither. Patients who used both prescription drugs and NHPs concurrently were more than three times more likely to experience an AE compared with those who used prescription drugs only (OR, P = 0.003, 95% CI: 1.47-6.91).

CONCLUSIONS

Increased AEs are reported in patients with HIV who combine NHPs and prescription medications, and no serious AEs were reported. Active surveillance was found to be feasible in this clinical setting.

Treatment optimization of maintenance immunosuppressive agents in pediatric renal transplant recipients

Introduction: Graft survival in pediatric kidney transplant patients has increased significantly within the last three decades, correlating with the discovery and utilization of new immunosuppressants as well as improvements in patient care. Despite these developments in graft survival for patients, there is still improvement needed, particularly in long-term care in pediatric patients receiving grafts from deceased donor patients. Maintenance immunosuppressive therapies have narrow therapeutic indices and are associated with high inter-individual and intra-individual variability.Areas covered: In this review, we examine the impact of pharmacokinetic variability on renal transplantation and its association with age, genetic polymorphisms, drug-drug interactions, drug-disease interactions, renal insufficiency, route of administration, and branded versus generic drug formulation. Pharmacodynamics are outlined in terms of the mechanism of action for each immunosuppressant, potential adverse effects, and the utility of pharmacodynamic biomarkers.Expert opinion: Acquiring abetter quantitative understanding of immunosuppressant pharmacokinetics and pharmacodynamic components should help clinicians implement treatment regimens to maintain the balance between therapeutic efficacy and drug-related toxicity.

Drug repurposing approach to fight COVID-19

Currently, there are no treatment options available for the deadly contagious disease, coronavirus disease 2019 (COVID-19). Drug repurposing is a process of identifying new uses for approved or investigational drugs and it is considered as a very effective strategy for drug discovery as it involves less time and cost to find a therapeutic agent in comparison to the de novo drug discovery process. The present review will focus on the repurposing efficacy of the currently used drugs against COVID-19 and their mechanisms of action, pharmacokinetics, dosing, safety, and their future perspective. Relevant articles with experimental studies conducted in-silico, in-vitro, in-vivo, clinical trials in humans, case reports, and news archives were selected for the review. Number of drugs such as remdesivir, favipiravir, ribavirin, lopinavir, ritonavir, darunavir, arbidol, chloroquine, hydroxychloroquine, tocilizumab and interferons have shown inhibitory effects against the SARS-CoV2 in-vitro as well as in clinical conditions. These drugs either act through virus-related targets such as RNA genome, polypeptide packing and uptake pathways or target host-related pathways involving angiotensin-converting enzyme-2 (ACE2) receptors and inflammatory pathways. Using the basic knowledge of viral pathogenesis and pharmacodynamics of drugs as well as using computational tools, many drugs are currently in pipeline to be repurposed. In the current scenario, repositioning of the drugs could be considered the new avenue for the treatment of COVID-19.

Structure and Function of Hepatobiliary ATP Binding Cassette Transporters

The liver is beyond any doubt the most important metabolic organ of the human body. This function requires an intensive crosstalk within liver cellular structures, but also with other organs. Membrane transport proteins are therefore of upmost importance as they represent the sensors and mediators that shuttle signals from outside to the inside of liver cells and/or vice versa. In this review, we summarize the known literature of liver transport proteins with a clear emphasis on functional and structural information on ATP binding cassette (ABC) transporters, which are expressed in the human liver. These primary active membrane transporters form one of the largest families of membrane proteins. In the liver, they play an essential role in for example bile formation or xenobiotic export. Our review provides a state of the art and comprehensive summary of the current knowledge of hepatobiliary ABC transporters. Clearly, our knowledge has improved with a breath-taking speed over the last few years and will expand further. Thus, this review will provide the status quo and will lay the foundation for new and exciting avenues in liver membrane transporter research.

How to overcome cardiovascular challenges in COVID-19 patients: a guide for common practice

The COVID-19 epidemic initially started in Wuhan, China in December 2019 due to SARS-CoV-2. SARS-CoV-2 is genetically similar to the bat beta-coronavirus genus, but the novel specie of this genus can infect humans. The most common clinical features of COVID-19 are fever, cough, myalgia, fatigue, expectoration, and dyspnea. The primary reported mortality rate was about 2-3% in China; however, it reached up to 10% among patients with underlying cardiovascular diseases. The primary epidemiological investigations showed a high prevalence of underlying cardiovascular diseases in more than 40% of infected patients. A high prevalence of hypertension, ischemic heart disease, and diabetes were reported among deceased patients in Italy. Previous experiments in different pandemic situations showed that the cardiovascular system has been affected in many ways. Previous studies on SARS-CoV and MERS-CoV reported that cardiovascular co-morbidities had a direct correlation with the risk of infection, the severity of disease, and the mortality rate. Therefore, brief and available protocols for controlling the negative effects of this novel respiratory infection on the cardiovascular system, especially in a high-risk populations with underlying cardiovascular conditions, is one of the most serious concerns among healthcare providers. Herein, we aimed to review the available data on the cardiac manifestation of COVID-19. Besides, we described useful maps for the better treatment of COVID-19 infection in patients with underlying cardiovascular conditions, as a high-risk group of patients.

The Challenge of Potential Drug-Drug Interactions Among People Living With HIV on Antiretroviral Therapy: A Cross-Sectional Study in Selected Provinces in China

Objectives

Potential drug–drug interactions (DDIs) are a significant therapeutic threat among human immunodeficiency virus (HIV)-positive individuals on antiretroviral (ARV) medications. DDIs involving ARV drugs in mainland China are unknown and insufficiently described. Herein, we investigated the prevalence and frequencies of potential ARV DDIs in Chinese people living with HIV (PLWH), then we assessed the risk factors associated with potential DDIs.

Methods

This study was conducted with HIV-positive adults undergoing ARV medications from multiple centers across China. The latest prescription of each participant was evaluated for potential DDIs using the Liverpool HIV drug interaction database. Multivariable logistic regressions were used to evaluate the factors associated with DDIs.

Results

Among 600 PLWH recruited, at least one non-HIV co-medication was observed in 511 (85.2%) individuals. A total of 2566 DDIs were identified, of which 11 (0.43%) and 311 (12.89%) were of contraindicated (red-flags) and dosage/timing adjustment required (orange-flags), respectively. Multivariate regression analysis revealed a higher risk of clinically significant DDIs (red- and orange-flagged comedication) associated with: the use of boosted protease inhibitors (p < 0.0001), boosted integrase strand transfer inhibitors (p < 0.0001), and non-nucleoside reverse transcriptase inhibitors-based ARV regimen (p < 0.0001); or the use of antiinfectives for systemic use (p < 0.0001), cardiovascular system drugs (p < 0.0001), nervous system drugs (p < 0.0001), fungal infection (p = 0.0071), and Herpes simplex virus infection (p = 0.0231).

Conclusions

Potential DDIs and inappropriate medications constitute a burden for people living with HIV in China. The knowledge of DDIs patterns and the scan for DDIs is crucial. Indeed, they can help to prevent drug-related adverse outcomes in such immunodeficient population.

Antiretroviral Adherence Level Necessary for HIV Viral Suppression Using Real-World Data

BACKGROUND

A benchmark of near-perfect adherence (≥95%) to antiretroviral therapy (ART) is often cited as necessary for HIV viral suppression. However, given newer, more effective ART medications, the threshold for viral suppression may be lower. We estimated the minimum ART adherence level necessary to achieve viral suppression.

SETTINGS

The Patient-centered HIV Care Model demonstration project.

METHODS

Adherence to ART was calculated using the proportion of days covered measure for the 365-day period before each viral load test result, and grouped into 5 categories (<50%, 50% to <80%, 80% to <85%, 85% to <90%, and ≥90%). Binomial regression analyses were conducted to determine factors associated with viral suppression (HIV RNA <200 copies/mL); demographics, proportion of days covered category, and ART regimen type were explanatory variables. Generalized estimating equations with an exchangeable working correlation matrix accounted for correlation within subjects. In addition, probit regression models were used to estimate adherence levels required to achieve viral suppression in 90% of HIV viral load tests.

RESULTS

The adjusted odds of viral suppression did not differ between persons with an adherence level of 80% to <85% or 85% to <90% and those with an adherence level of ≥90%. In addition, the overall estimated adherence level necessary to achieve viral suppression in 90% of viral load tests was 82% and varied by regimen type; integrase inhibitor- and nonnucleoside reverse transcriptase inhibitor-based regimens achieved 90% viral suppression with adherence levels of 75% and 78%, respectively.

CONCLUSIONS

The ART adherence level necessary to reach HIV viral suppression may be lower than previously thought and may be regimen-dependent.

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.

Profile of drug-drug interactions and impact on the effectiveness of antiretroviral therapy among patients living with HIV followed at an Infectious Diseases Referral Center in Belo Horizonte, Brazil

HIV infection may be considered a chronic condition for people living with HIV with access to antiretrovirals and this has effectively increased survival. Moreover, this has also facilitated the emergence of other comorbidities increasing the risk for drug–drug interactions and polypharmacy. The profile of these interactions as well as their consequences for people living with HIV are still not completely elucidated. The objectives of this study were to describe the profile of these interactions, their prevalence and their classification according to the potential for significant or non-significant drug–drug interactions. From June 2015 to July 2016, people living with HIV on follow-up at an Infectious Diseases Referral Center in Belo Horizonte, Brazil have been investigated for the presence of drug–drug interactions. A total of 304 patients were included and the majority (75%) had less than 50 years of age, male (66.4%), and 37.8% self-defined as brown skinned. Approximately 24% were on five or more medications and half of them presented with drug–drug interactions. Patients older than 50 years had a higher frequency of antiretrovirals drug–drug interactions with other drugs compared to younger patients (p = 0.002). No relationship was found between the number of drug–drug interactions and the effectiveness of antiretrovirals. As expected, the higher the number of non-HIV medications used (OR = 1.129; 95%CI 1.004–1.209; p = 0.04) was associated with an increase in drug–drug interactions. The high prevalence of drug–drug interactions found and the data collected should be useful to establish measures of quaternary prevention and to increase the medication security for people living with HIV.

ATP-binding Cassette Exporters: Structure and Mechanism with a Focus on P-glycoprotein and MRP1

BACKGROUND

Proteins that belong to the ATP-binding cassette superfamily include transporters that mediate the efflux of substrates from cells. Among these exporters, P-glycoprotein and MRP1 are involved in cancer multidrug resistance, protection from endo and xenobiotics, determination of drug pharmacokinetics, and the pathophysiology of a variety of disorders.

OBJECTIVE

To review the information available on ATP-binding cassette exporters, with a focus on Pglycoprotein, MRP1 and related proteins. We describe tissue localization and function of these transporters in health and disease, and discuss the mechanisms of substrate transport. We also correlate recent structural information with the function of the exporters, and discuss details of their molecular mechanism with a focus on the nucleotide-binding domains.

METHODS

Evaluation of selected publications on the structure and function of ATP-binding cassette proteins.

CONCLUSIONS

Conformational changes on the nucleotide-binding domains side of the exporters switch the accessibility of the substrate-binding pocket between the inside and outside, which is coupled to substrate efflux. However, there is no agreement on the magnitude and nature of the changes at the nucleotide- binding domains side that drive the alternate-accessibility. Comparison of the structures of Pglycoprotein and MRP1 helps explain differences in substrate selectivity and the bases for polyspecificity. P-glycoprotein substrates are hydrophobic and/or weak bases, and polyspecificity is explained by a flexible hydrophobic multi-binding site that has a few acidic patches. MRP1 substrates are mostly organic acids, and its polyspecificity is due to a single bipartite binding site that is flexible and displays positive charge.

Healthcare and economic impact

This chapter reviews the current model of HIV patient care and its economic impact. There are clinical and geographical differences in the care HIV patients receive and a need to develop new models of comprehen-sive HIV care has been identified. HIV infection in Spain is an important and expensive public health problem. The main costs are due to an-tiretroviral therapy, indirect costs and the cost of admission, consultation and diagnostic testing. A strong correlation between severity and cost has been identified. Patients diagnosed late have a poorer clinical course, increased mortality and require more medical and therapeutic resources. Early detection of the disease significantly improves the clinical outcomes of patients. The increased number of patients receiving treatment and their progressive ageing will increase costs of HIV healthcare in the coming years.

Clinical care of patients with HIV

There has been a significant change in the clinical characteristics of people living with HIV, with new needs arising that must be tackled. The life expectancy of a subject diagnosed early with HIV infection and recei-ving suppressive antiretroviral therapy is currently on a par with the life expectancy of the general popula-tion. HIV is now a chronic treatable disease and requires a multidisciplinary approach that includes both the hospital medicine specialties and primary care physicians. The fragmented model to provide social and medical healthcare hinders the proper management of patients with HIV infection. There is significant clinical and geographical variability in the healthcare provided for HIV infection in Spain and the need to define and implement new models of healthcare delivery for this disease has been identified.

Burden of Exposure to Potential Interactions Between Antiretroviral and Non-Antiretroviral Medications in a Population of HIV-Positive Patients Aged 50 Years or Older

BACKGROUND

As HIV-infected patients aged 50 years or older are at increased risk of comorbidities and multidrug treatments, we examined their exposure to the potential drug-drug interactions (PDDIs) of antiretroviral (ARV) and other medications.

METHODS

This cross-sectional study involved the patients aged 50 years or older receiving ARV and non-ARV medications at our clinic. PDDIs were identified using the University of Liverpool HIV Drug Interaction Checker. Logistic regression models were used to assess risk factors for PDDIs. The American Geriatrics Society Beers Criteria were used to identify potentially inappropriate medications (PIMs).

RESULTS

A total of 395 (53.9%) of 744 patients showed ≥1 PDDI: 47.4% ≥ 1 amber-PDDI (comedications requiring appropriate management) and 5.6% ≥ 1 red-PDDI (contraindicated comedications). A higher risk of PDDIs was associated with the use of ≥5 medications (P < 0.001), of antiosteoporotics (P < 0.001), calcium channel blockers (P < 0.001), anti-benign prostatic hypertrophy agents (P < 0.001), hypnotics/sedatives (P = 0.022), and anticoagulants (P = 0.006). A higher risk of red-PDDIs was associated with the use of antacids (P < 0.001), anti-benign prostatic hypertrophy agents (P < 0.001) and antipsychotics (P = 0.023). The use of nucleoside reverse transcriptase inhibitor + nonnucleoside reverse transcriptase inhibitor and nucleoside reverse transcriptase inhibitor + integrase strand transfer inhibitor rather than protease inhibitor-based regimens was associated with a reduced risk of PDDIs (P < 0.001). Overall, 119 (16.0%) patients were receiving PIMs (mainly hypnotics/sedatives) and 49 (41.2%) of them had PDDIs able to increase the blood levels of these medications.

CONCLUSIONS

Older patients with HIV are highly exposed to PDDIs between ARVs and comedications. The knowledge of their complete medication regimens and the screening for PDDIs and PIMs is therefore crucial to prevent drug-related adverse outcomes in this population.

Promiscuous Ligands from Experimentally Determined Structures, Binding Conformations, and Protein Family-Dependent Interaction Hotspots

Compound promiscuity is often attributed to nonspecific binding or assay artifacts. On the other hand, it is well-known that many pharmaceutically relevant compounds are capable of engaging multiple targets in vivo, giving rise to polypharmacology. To explore and better understand promiscuous binding characteristics of small molecules, we have searched X-ray structures (and very few qualifying solution structures) for ligands that bind to multiple distantly related or unrelated target proteins. Experimental structures of a given ligand bound to different targets represent high-confidence data for exploring promiscuous binding events. A total of 192 ligands were identified that formed crystallographic complexes with proteins from different families and for which activity data were available. These "multifamily" compounds included endogenous ligands and were often more polar than other bound compounds and active in the submicromolar range. Unexpectedly, many promiscuous ligands displayed conserved or similar binding conformations in different active sites. Others were found to conformationally adjust to binding sites of different architectures. A comprehensive analysis of ligand-target interactions revealed that multifamily ligands frequently formed different interaction hotspots in binding sites, even if their bound conformations were similar, thus providing a rationale for promiscuous binding events at the molecular level of detail. As a part of this work, all multifamily ligands we have identified and associated activity data are made freely available.

[Nephrotoxicity of antiretrovirals other than tenofovir]

The remarkable improvement of the outcome of HIV infection came with the price of substantial toxicity of some antiretrovirals. The first molecules used to treat HIV included an important nephrotoxicity. Zalcitabine, stavudine and didanosine can induce severe lactic acidosis. Lactate production is enhanced and the renal capacity to regulate pH is overwhelmed. However, this side effect is not due to a direct dysfunction of the kidneys. Zalcitabine was withdrawn from the market because of this risk. Indinavir, a protease inhibitor, is soluble only in very acidic solutions. Consequently, the small fraction that is excreted in the urine precipitates and can be responsible for uro-nephrolithiasis, leukocyturia, cristalluria, obstructive acute kidney failure, and acute or chronic interstitial nephritis. This is the reason why indinavir is almost not prescribed nowadays, even if it is still marketed. In addition to the direct nephrotoxicity of some antiretrovirals, anti-HIV treatment also includes a toxicity which pathophysiology is not completely elucidated. This nephrotoxicity is the consequence of organ accelerated ageing and of an increased vascular risk. Kidney vascularization (from renal arteries to capillaries) is essential to kidney function and all cardiovascular risks are also renal risks. It is now clearly established that combined antiretroviral treatment increases the vascular risk. A better comprehension of the links between HIV infection, its treatment and very long-term kidney risk is needed to improve the complex management of patients who have now cumulated several decades of HIV infection and treatment with various toxicities.

Frequency and severity of potential drug interactions in a cohort of HIV-infected patients Identified through a Multidisciplinary team

OBJECTIVES

Interactions between antiretroviral treatment (ART) and comedications are a concern in HIV-infected patients. This study aimed to determine the frequency and severity of potential drug-drug interactions (PDDIs) with ART in our setting.

METHODS

Observational study by a multidisciplinary team in 1259 consecutive HIV patients (March 2015-September 2016). Data on demographics, toxic habits, comorbidities, and current ART were collected. A structured questionnaire recorded concomitant medications (including occasional and over-the-counter drugs). PDDIs were classified into four categories: (1) no interactions, (2) mild (clinically non-significant), (3) moderate (requiring close monitoring or drug modification/dose adjustment), and (4) severe (contraindicated).

STATISTICAL ANALYSIS

chi-square test, logistic regression analysis.

RESULTS

In total, 881 (70%) patients took comedication, and 563 (44.7%) had ≥ PDDI. Forty-one comedicated patients (4.6%) had severe and 522 (59.2%) moderate PDDIs. Moderate PDDIs mainly involved cardiovascular (53.8%) and central nervous system (40.2%) drugs. Independent risk factors for PDDIs were ART containing a boosted protease inhibitor (odds ratio [OR]=9.11, 95% confidence interval [CI] 5.15-16.11; p = 0.0001) and/or non-nucleoside reverse transcriptase (NNRTI) (OR = 4.34, 95%CI 2.49-7.55; p = 0.0001), HCV co-infection (OR = 3.26, 95%CI 2.15-4.93; p = 0.0001), and use of two or more comedications (OR = 3.36, 95%CI 2.27-4.97; p = 0.0001). Adherence and effectiveness of ART were similar in patients with and without PDDIs. The team made 133 recommendations related to comedications (drug change or dose adjustment) or ART (drug switch or change in administration schedule).

CONCLUSIONS

Systematic evaluation detected a significant percentage of PDDIs requiring an intervention in HIV patients on ART. Monitoring and advice about drug-drug interactions should be part of routine practice.

Kidney Disease in HIV: Moving beyond HIV-Associated Nephropathy

In developed countries, remarkable advances in antiretroviral therapy have transformed HIV infection into a chronic condition. As a result, HIV-associated nephropathy, the classic HIV-driven kidney lesion among individuals of African descent, has largely disappeared in these regions. However, HIV-positive blacks continue to have much higher rates of ESRD than HIV-positive whites, which could be attributed to the APOL1 renal risk variants. Additionally, HIV-positive individuals face adverse consequences beyond HIV itself, including traditional risk factors for CKD and nephrotoxic effects of antiretroviral therapy. Concerns for nephrotoxicity also extend to HIV-negative individuals using tenofovir disoproxil fumarate-based pre-exposure prophylaxis for the prevention of HIV infection. Therefore, CKD remains an important comorbid condition in the HIV-positive population and an emerging concern among HIV-negative persons receiving pre-exposure prophylaxis. With the improved longevity of HIV-positive individuals, a kidney transplant has become a viable option for many who have progressed to ESRD. Herein, we review the growing knowledge regarding the APOL1 renal risk variants in the context of HIV infection, antiretroviral therapy-related nephrotoxicity, and developments in kidney transplantation among HIV-positive individuals.

How I treat patients with HIV-related hematological malignancies using hematopoietic cell transplantation

Hematopoietic cell transplantation (HCT) has now been shown to be safe and effective for selected HIV-infected patients with hematological malignancies. Autologous HCT is now the standard of care for patients with HIV-related lymphomas who otherwise meet standard transplant criteria. Limited data also support use of allogeneic HCT (alloHCT) in selected HIV-infected patients who meet standard transplant criteria. We recommend enrolling patients in clinical trials that offer access to CCR5Δ32 homozygous donors, if available. HIV-infected patients requiring HCT may also be considered for participation in trials evaluating the activity of gene-modified hematopoietic stem cells in conferring resistance to HIV infection. To be considered for HCT, patients must have HIV infection that is responsive to combination antiretroviral therapy (cART). Careful planning for the peri-HCT management of the cART can avoid risk of significant drug interactions and development of cART-resistant HIV. In general, we recommend against the use of boosted proteasome inhibitors and nonnucleotide reverse transcriptase inhibitors in the cART regimen, in favor of nucleoside reverse transcriptase inhibitors and integrase inhibitors (without cobicistat). After HCT, patients must be closely monitored for development of opportunistic infections (OI), such as cytomegalovirus. Prevention of OI should include prophylactic and pre-emptive antimicrobials.

Antiretroviral Therapy for Prevention of Human Immunodeficiency Virus Infection

Human immunodeficiency virus (HIV) infection is considered a chronic medical condition. Several new drugs are available, including fixed-dose combination tablets, that have greatly simplified combination antiretroviral therapy (ART) regimens to treat HIV, while increasing the life-expectancy of infected individuals. In the last decade, multiple well-regarded studies have established the benefits of using ART in high-risk, HIV-negative persons to prevent HIV acquisition. The primary care provider must not only understand commonly encountered issues pertaining to ART, such as toxicities and drug interactions, but also needs to be aware of using ART for HIV prevention.

The neurobiology of HIV and its impact on cognitive reserve: A review of cognitive interventions for an aging population

The medications used to treat HIV have reduced the severity of cognitive deficits; yet, nearly half of adults with HIV still exhibit some degree of cognitive deficits, referred to as HIV-associated neurocognitive disorder or HAND. These cognitive deficits interfere with everyday functioning such as emotional regulation, medication adherence, instrumental activities of daily living, and even driving a vehicle. As adults are expected to live a normal lifespan, the process of aging in this clinical population may exacerbate such cognitive deficits. Therefore, it is important to understand the neurobiological mechanisms of HIV on cognitive reserve and develop interventions that are either neuroprotective or compensate for such cognitive deficits. Within the context of cognitive reserve, this article delivers a state of the science perspective on the causes of HAND and provides possible interventions for addressing such cognitive deficits. Suggestions for future research are also provided.