Pharmacologic aspects of new antiretroviral drugs

Evolving mechanisms and presentations of cardiovascular disease in people with HIV: implications for management

People with HIV (PWH) are at elevated risk for cardiovascular diseases (CVDs), including myocardial infarction, heart failure, and sudden cardiac death, among other CVD manifestations. Chronic immune dysregulation resulting in persistent inflammation is common among PWH, particularly those with sustained viremia and impaired CD4+ T cell recovery. This inflammatory milieu is a major contributor to CVDs among PWH, in concert with common comorbidities (such as dyslipidemia and smoking) and, to a lesser extent, off-target effects of antiretroviral therapy. In this review, we discuss the clinical and mechanistic evidence surrounding heightened CVD risks among PWH, implications for specific CVD manifestations, and practical guidance for management in the setting of evolving data.

Precision medicine for HIV: where are we?

To date, antiretroviral therapy is highly effective in HIV-affected patients, but the individualization of such a life-long therapy may be advised. This review briefly summarizes the main factors involved in the potential personalization of antiretroviral treatment. Relevant articles in English were identified by PubMed and recent congresses’ abstracts. Foremost influences concerning pharmacodynamics, therapeutic drug monitoring, pharmacogenetics, comorbidities, immune recovery and viral characteristics affecting the healthcare of HIV-positive patients are listed here. Furthermore, pharmacoeconomic aspects are mentioned. Applying pharmacokinetic and pharmacogenetic knowledge may be informative and guide the better choice of treatment in order to achieve long-term efficacy and avoid adverse events. Randomized investigations of the clinical relevance of tailored antiretroviral regimens are needed in order to obtain a better management of HIV/AIDS-affected patients.

Evidence-based review of statin use in patients with HIV on antiretroviral therapy

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Cardiovascular disease is up to two times more prevalent in patient with HIV.

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Based on pharmacokinetic and clinical data, atorvastatin and pravastatin are generally considered safe for HIV patients receiving ART.

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Rosuavstatin is generally safe if started at a low dose and a maximum 20 mg per day.

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Fluvastatin, lovastatin, and simvastatin should be avoided in patients with HIV receiving ART.

Introduction

As a result of improved safe and effective therapeutic options for human immunodeficiency virus (HIV), life expectancy of those living with HIV is increasing leading to new challenges (e.g., management of chronic diseases). Some chronic diseases (e.g., cardiovascular disease [CVD]), are up to two times more prevalent in patients with HIV. Statins are a mainstay of therapy for prevention of CVD; but, clinicians should be aware that not all statins are appropriate for use in the HIV population, especially those receiving antiretroviral therapy (ART). The purpose of this article is to review the pharmacokinetic and clinical data for statin therapy in HIV-infected patients receiving ART.

Methods

A systematic literature search using PubMed and MEDLINE databases was performed using each statin drug name combined with HIV, pharmacokinetics, AIDS, and/or human immunodeficiency virus. English language trials published from 1946 to November 2016 were considered, and results were limited to clinical efficacy trials.

Results

In general, atorvastatin and pravastatin are safe and effective for patients treated with protease-inhibitor (PI) or non-nucleoside reverse transcriptase inhibitor-based ART. Rosuvastatin is generally considered safe if started at a low dose, but should be avoided if possible in patients receiving PI-based ART. Pitavastatin has limited supporting evidence, but appears safe for use based on its pharmacokinetic properties and low number of drug interactions. Fluvastatin, lovastatin, and simvastatin should be avoided in patients receiving ART due to drug interactions, adverse events, and/or limited clinical data.

Conclusion

Clinicians need to be familiar with the intricacies of statin selection for the prevention of CVD in patients with HIV on ART.

Subjective wellbeing and ‘felt’ stigma when living with HIV

PURPOSE

The impact of stigma on subjective wellbeing was explored in adults living with HIV in Australia and the USA. It was hypothesised that this population would report poorer subjective wellbeing than the general population and that ‘felt’ stigma would contribute significantly to reported levels of subjective wellbeing.

METHODS

A total of 274 participants were recruited through Australian AIDS councils and HIV-specific online support groups. Participants completed a composite questionnaire comprising the personal wellbeing index—adult (PWI-A), the HIV version of the unsupportive social interactions inventory (USII) and demographic and health-related items. The PWI-A total score was used to form a personal wellbeing index, ranging from 0 to 100.

RESULTS

Participants reported mean PWI-A total scores of 54.7, considerably below the normative range of 70–80 for Western populations. There was a strong negative correlation between PWI-A total scores and USII total scores with the experience of high levels of unsupportive social interactions being associated with reduced levels of subjective wellbeing.

CONCLUSIONS

Our study suggests that despite antidiscrimination legislation, ‘felt’ stigma in the form of unsupportive social interactions continues to exert a negative impact on subjective wellbeing. Reduced subjective wellbeing may increase the risk of adverse health behaviours, such as medication non-adherence, substance abuse, risky sexual behaviours and non-disclosure of HIV serostatus.

AtriplaR/anti-TB combination in TB/HIV patients. Drug in focus

Background

Co-administration of anti-tuberculosis and antiretroviral therapy is often inevitable in high-burden countries where tuberculosis is the most common opportunistic infection associated with HIV/AIDS. Concurrent use of rifampicin and several antiretroviral drugs is complicated by pharmacokinetic drug-drug interaction.

Method

Pubmed and Google search following the key words tuberculosis, HIV, emtricitabine, tenofovir efavirenz, interaction were used to find relevant information on each drug of the fixed dose combination Atripla^R

Results

Information on generic name, trade name, pharmacokinetic parameter, metabolism and the pharmacokinetic interaction with Anti-TB drugs of emtricitabine, tenofovir, and efavirenz was obtained.

Conclusion

Fixed dose combination of emtricitabine/tenofovir/efavirenz (ATRIPLA^R) which has been approved by Food and Drug Administration shows promising results as far as safety and efficacy is concerned in TB/HIV co-infection patients, hence can be considered effective and safe antiretroviral drug in TB/HIV management for adult and children above 3 years of age.

Randomized controlled trial evaluating pictogram augmentation of HIV medication information

BACKGROUND

Antiretroviral therapy for the management of HIV typically requires the chronic use of 3 or more medications. As such, patients with HIV are required to manage complex dosing schedules and are at risk of multiple potential adverse effects. The use of pictograms on medication vials as a means of improving patients' understanding of medication information has been shown to positively influence understanding and adherence compared to those using text alone.

OBJECTIVE

To determine whether pictograms (Pharmaglyph) increase patient recall of targeted information associated with HIV medications and whether patients can interpret the intended meaning of pictograms that they had not seen previously.

METHODS

A randomized, controlled trial was conducted in HIV-positive patients aged 19 years or older who were receiving a new prescription for an antiretroviral medication from the ambulatory pharmacy at St. Paul's Hospital in Vancouver, British Columbia, Canada. Participants were randomized to receive either pictogram-enhanced medication information or standard counseling. At the first follow-up visit, each patient's recall of the medication information was evaluated, and differences between groups were compared.

RESULTS

Eighty-two subjects were randomized, 40 to the intervention group and 42 to the control arm. The mean (SD) number of HIV medications was nearly equal between the intervention and control groups: 3.0 (1.5) and 3.1 (1.4), respectively. After a mean of 34 days, 33 patients in the intervention arm and 39 in the control arm completed the study. The majority (88%) of the targeted pieces of information in the intervention group were correctly identified at follow-up, compared to only 2% in the control group (Fisher exact test; p < 0.0001).

CONCLUSIONS

Pictograms improve the recall of targeted medication information among patients receiving antiretroviral therapy for HIV management; however, this appears to be dependent on the fact that these patients received a verbal explanation of each pictogram prior to use.

Antiretroviral drugs in pediatric HIV-infected patients: pharmacokinetic and practical challenges

Antiretroviral (ARV) therapy has been shown to achieve high therapeutic efficacy in treating pediatric HIV disease. The delivery of affordable, child friendly, and easy to store and administer ARV drugs is key to the successful management of HIV in children. In recent years, significant progress has been made in scaling up the access to pediatric ARV therapy among children worldwide. Despite the improved ARV drug access, multiple challenges remain concerning palatability and efficient delivery of ARV drugs to children from infancy into adolescence. Data are limited regarding developmental changes in pharmacokinetics of individual ARV drugs, and pediatric and adult fixed-dose combinations. This review provides a practical discussion regarding the pharmacokinetics of ARV agents in pediatric HIV-infected patients, as well as the practical challenges of currently available formulations, such as palatability of liquid formulations, challenges of crushing tablets, and using adult and pediatric fixed-dose combinations.

Drug interactions of new antiretroviral drugs

A systematic review was made of the drug interactions of new antiretroviral drugs. In order to do this a search was made in Pubmed to find articles published from January 2007 to September 2009 and the full-text articles which contained information about new antiretroviral drugs were selected. This search was then complemented with information from the technical specifications of the drugs and consultations made on webpages specialized in antiretroviral interactions: www.interaccioneshiv.com and www.hiv-druginteractions.org. The information about the possible interactions of new antiretroviral drugs with one another and with the therapeutic groups which are most widely used in patients infected with the human immunodeficiency virus was analyzed.

Pharmacotherapy of HIV-1 Infection: Focus on CCR5 Antagonist Maraviroc

Sustained inhibition of HIV-1, the goal of antiretroviral therapy, is often impeded by the emergence of viral drug resistance. For patients infected with HIV-1 resistant to conventional drugs from the viral reverse transcriptase and protease inhibitor classes, the recently approved entry and integration inhibitors effectively suppress HIV-1 and offer additional therapeutic options. Entry inhibitors are particularly attractive because, unlike conventional antiretrovirals, they target HIV-1 extracellularly, thereby sparing cells from both viral- and drug-induced toxicities. The fusion inhibitor enfuvirtide and the CCR5 antagonist maraviroc are the first entry inhibitors licensed for patients with drug-resistant HIV-1, with maraviroc restricted to those infected with CCR5-tropic HIV-1 (R5 HIV-1) only. Vicriviroc (another CCR5 antagonist) is in Phase III clinical trials, whereas the CCR5 antibodies PRO 140 and HGS 004 are in early stages of clinical development. Potent antiviral synergy between maraviroc and CCR5 antibodies, coupled with distinct patterns of resistance, suggest their combinations might be particularly effective in patients. In addition, given that oral administration of maraviroc achieves high drug levels in cervicovaginal fluid, combinations of maraviroc and other CCR5 inhibitors could be effective in preventing HIV-1 transmission. Moreover, since CCR5 antagonists prevent rejection of transplanted organs, maraviroc could both suppress HIV-1 and prolong organ survival for the growing number of HIV-1 patients with kidney or liver failure necessitating organ transplantation. Thus, maraviroc offers an important treatment option for patients with drug-resistant R5 HIV-1, who presently account for >50% of drug-resistance cases.