Metabolic effects of protease inhibitor-sparing antiretroviral regimens given as initial treatment of HIV-1 Infection (AIDS Clinical Trials Group Study A5095)

Coronary artery disease in patients with human immunodeficiency virus infection

The life expectancy of people infected with human immunodeficiency virus (HIV) is rising due to better access to combination anti-retroviral therapy (ART). Although ART has reduced acquired immune deficiency syndrome (AIDS) related mortality and morbidity, there has been an increase in non-AIDS defining illnesses such as diabetes mellitus, hypercholesterolemia and coronary artery disease (CAD). HIV is a disease marked by inflammation which has been associated with specific biological vascular processes increasing the risk of premature atherosclerosis. The combination of pre-existing risk factors, atherosclerosis, ART, opportunistic infections and coagulopathy contributes to rising CAD incidence. The prevalence of CAD has emerged as a major contributor of morbidity in these patients due to longer life expectancy. However, ART has been associated with lipodystrophy, dyslipidemia, insulin resistance, diabetes mellitus and CAD. These adverse effects, along with drug-drug interactions when ART is combined with cardiovascular drugs, result in significant challenges in the care of this group of patients. Exercise tolerance testing, echocardiography, myocardial perfusion imaging, coronary computed tomography angiography and magnetic resonance imaging help in the diagnosis of CAD and heart failure and help predict cardiovascular outcomes in a manner similar to non-infected individuals. This review will highlight the pathogenesis and factors that link HIV to CAD, presentation and treatment of HIV-patients presenting with CAD and review briefly the cardiac imaging modalities used to identify this entity and help prognosticate future outcomes.

Comparative efficacy and safety of dolutegravir relative to common core agents in treatment-naïve patients infected with HIV-1: a systematic review and network meta-analysis

Background

Network meta-analyses (NMAs) provide comparative treatment effects estimates in the absence of head-to-head randomized controlled trials (RCTs). This NMA compared the efficacy and safety of dolutegravir (DTG) with other recommended or commonly used core antiretroviral agents.

Methods

A systematic review identified phase 3/4 RCTs in treatment-naïve patients with HIV-1 receiving core agents: ritonavir-boosted protease inhibitors (PIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), or integrase strand inhibitors (INSTIs). Efficacy (virologic suppression [VS], CD4⁺ cell count change from baseline) and safety (adverse events [AEs], discontinuations, discontinuation due to AEs, lipid changes) were analyzed at Week 48 using Bayesian NMA methodology, which allowed calculation of probabilistic results. Subgroup analyses were conducted for VS (baseline viral load [VL] ≤/> 100,000copies/mL, ≤/> 500,000copies/mL; baseline CD4⁺ ≤/>200cells/μL). Results were adjusted for the nucleoside/nucleotide reverse transcriptase inhibitors (NRTI) combined with the core agent (except subgroup analyses).

Results

The NMA included 36 studies; 2 additional studies were included in subgroup analyses only. Odds of achieving VS with DTG were statistically superior to PIs (odds ratios [ORs] 1.78–2.59) and NNRTIs (ORs 1.51–1.86), and similar but numerically higher than other INSTIs. CD4⁺ count increase was significantly greater with DTG than PIs (difference: 23.63–31.47 cells/μL) and efavirenz (difference: 34.54 cells/μL), and similar to other core agents. INSTIs were more likely to result in patients achieving VS versus PIs (probability: 76–100%) and NNRTIs (probability: 50–100%), and a greater CD4⁺ count increase versus PIs (probability: 72–100%) and NNRTIs (probability: 60–100%). DTG was more likely to result in patients achieving VS (probability: 94–100%), and a greater CD4⁺ count increase (probability: 53–100%) versus other core agents, including INSTIs (probability: 94–97% and 53–93%, respectively). Safety outcomes with DTG were generally similar to other core agents. In patients with baseline VL > 100,000copies/mL or ≤ 200 CD4⁺cells/μL (18 studies), odds of achieving VS with DTG were superior or similar to other core agents.

Conclusion

INSTI core agents had superior efficacy and similar safety to PIs and NNRTIs at Week 48 in treatment-naïve patients with HIV-1, with DTG being among the most efficacious, including in patients with baseline VL > 100,000copies/mL or ≤ 200 CD4⁺cells/μL, who can be difficult to treat.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-3975-6) contains supplementary material, which is available to authorized users.

Right Ventricular Hypertrophy and Dilation in Patients With Human Immunodeficiency Virus in the Absence of Clinical or Echocardiographic Pulmonary Hypertension

BACKGROUND

Involvement of right-sided heart chambers (RSHCs) in patients infected with human immunodeficiency virus (HIV) is common and is usually attributed to pulmonary arterial or venous hypertension (PH). However, myocardial involvement in patients with HIV is also common and might affect RSHCs even in the absence of overt PH. Our aim was to define morphologic and functional alterations in RSHC in patients with HIV and without PH.

METHODS AND RESULTS

A total of 50 asymptomatic patients with HIV and 25 control subjects without clinical or echocardiographic signs for PH were included in the study. Transthoracic echocardiography was used to obtain measurements. Patients with HIV had significantly increased right ventricular end-diastolic diameter (RVEDD) and right ventricular free wall thickness (RVFWT), as well as increased right atrial area and pulmonary arterial diameter, compared with control subjects. After adjustment for age, sex, and body surface area, RVFWT (average 1.81 mm, 95% confidence interval [CI] 0.35-3.26 mm) and RVEDD (average 6.82 mm, 95% CI 2.40-11.24 mm) were significantly higher in subjects infected with HIV. More patients with right ventricular hypertrophy were on antiretroviral treatment, and RVFWT was on average 1.3 mm higher (95% CI 0.24-2.37 mm) in patients on antiretroviral treatment after adjustment for confounders.

CONCLUSIONS

These findings suggest that alterations in RSHCs were present in patients with HIV without PH.

Efavirenz: What is known about the cellular mechanisms responsible for its adverse effects

The HIV infection remains an important health problem worldwide. However, due to the efficacy of combined antiretroviral therapy (cART), it has ceased to be a mortal condition, becoming a chronic disease instead. Efavirenz, the most prescribed non-nucleoside analogue reverse transcriptase inhibitor (NNRTI), has been a key component of cART since its commercialization in 1998. Though still a drug of choice in many countries, its primacy has been challenged by the arrival of newer antiretroviral agents with better toxicity profiles and treatment adherence. The major side effects related to EFV have been widely described in clinical studies, however the mechanisms that participate in their pathogenesis remain largely ununderstood. This review provides an insight into the cellular and molecular mechanisms responsible for the development of the most significant undesired effects induced by efavirenz, both short- and long-term, revealed by in vitro and in vivo experimental pharmacological research. Growing evidence implicates the drug in energy metabolism, mitochondrial function, and other cellular processes involved in stress responses including oxidative stress, inflammation and autophagy.

Safety and Efficacy of Atorvastatin in Human Immunodeficiency Virus-infected Children, Adolescents and Young Adults With Hyperlipidemia

BACKGROUND

Human immunodeficiency virus (HIV)-infected children receiving antiretroviral therapy (ART) have increased prevalence of hyperlipidemia and risk factors for cardiovascular disease. No studies have investigated the efficacy and safety of statins in this population.

METHODS

HIV-infected youth 10 to <24 years of age on stable ART with low-density lipoprotein cholesterol (LDL-C) ≥130 mg/dL for ≥6 months initiated atorvastatin 10 mg once daily. Atorvastatin was increased to 20 mg if LDL-C efficacy criteria (LDL-C < 110 mg/dL or decreased ≥30% from baseline) were not met at week 4. Primary outcomes were safety and efficacy.

RESULTS

Twenty-eight youth initiated atorvastatin; 7 were 10-15 years and 21 were 15-24 years. Mean baseline LDL-C was 161 mg/dL (standard deviation 19 mg/dL). Efficacy criteria were met at week 4 by 17 of 27 (63%) participants. Atorvastatin was increased to 20 mg in 10 participants. Mean LDL-C decreased from baseline by 30% (90% confidence interval: 26%, 35%) at week 4, 28% (90% confidence interval: 23%, 33%) at week 24 and 26% (90% confidence interval: 20%, 33%) at week 48. LDL-C was less than 110 mg/dL in 44% at week 4, 42% at week 12 and 46% at weeks 24 and 48. Total cholesterol, non high-density lipoprotein (non-HDL)-C and apolipoprotein B decreased significantly, but IL-6 and high-sensitivity C-reactive protein did not. Two participants in the younger age group discontinued study for toxicities possibly related to atorvastatin.

CONCLUSIONS

Atorvastatin lowered total cholesterol, LDL-C, non HDL-C and apolipoprotein B in HIV-infected youth with ART-associated hyperlipidemia. Atorvastatin could be considered for HIV-infected children with hyperlipidemia, but safety monitoring is important particularly in younger children.

Characterization of lipid composition and high-density lipoprotein function in HIV-infected individuals on stable antiretroviral regimens

There is an increase in the cardiovascular disease (CVD) morbidity in individuals infected with HIV that may be due to inflammatory lipid modulation not captured by traditional lipid measures. The objective of this study was to perform advanced lipoprotein phenotyping inclusive of the high-density lipoprotein (HDL) cholesterol efflux capacity and lipoprotein particle concentration and size in a well-phenotyped group of 118 patients infected with HIV. We used simple and multivariable analyses to determine the associations between advanced lipoprotein parameters and known cardiometabolic risk factors. Participants were on stable antiretroviral therapy (ART) and had benign traditional lipid panels [median total cholesterol, low-density lipoprotein (LDL)-C, HDL-C, and triglycerides of 178 mg/dl, 108 mg/dl, 44 mg/dl, and 122.5 mg/dl, respectively]. However, advanced lipoprotein phenotyping demonstrated an elevation of LDL particle number (median of 1,233 nmol/liter) and a decrease in LDL size (median of 20.4 nm), along with a decrease in protective, large HDL particles (median of 3.15 μmol/liter) and reduced HDL cholesterol efflux capacity in comparison to controls of other studies. HDL cholesterol efflux capacity was associated with HDL levels (β=0.395, p<0.001), small LDL particle concentration (β=-0.198, p=0.031), insulin sensitivity by the Matsuda index (β=0.218, p=0.029), and the Framingham Risk Score (β=-0.184, p=0.046). We demonstrate an atherogenic lipoprotein profile by NMR spectroscopy and HDL efflux measurement in a group of HIV-infected patients on stable ART with normal lipid panels.

HIV-associated lipodystrophy: a review from a Brazilian perspective

The prognosis of human immunodeficiency virus (HIV)-infected individuals has dramatically improved worldwide since the introduction of highly antiretroviral therapy. Nevertheless, along with the decrease in mortality, several body modifications not initially related to HIV infection have been reported. Disorders in lipid and glucose metabolism, accompanied by body shape abnormalities and alterations in fat distribution, began to be described. A syndrome, named "HIV-associated lipodystrophy syndrome", was coined to classify these clinical spectrum aspects. This syndrome involves not only metabolic alterations but also fat redistribution, with lipoatrophy due to subcutaneous fat loss (predominantly in the face and lower limbs) and lipohypertrophy related to central fat gain. These changes in body shape are very important to be recognized, as they are associated with worse morbidity and mortality. Self-esteem difficulties related to body alterations might lead to treatment failures due to medication adherence problems. Moreover, these alterations have been associated with an increased risk of cardiovascular events. Therefore, it is extremely important to identify this syndrome early in order to provide an even better quality of life for this population, as the clinical approach is not easy. Treatment change, medications to treat dyslipidemia, and surgical intervention are instruments to be used to try to correct these abnormalities. The aim of this study is to review clinical presentation, diagnosis, and management of body shape and metabolic complications of HIV infection from a Brazilian perspective, a medium income country with a large number of patients on antiretroviral therapy.

Switching safely: pharmacokinetics, efficacy and safety of switching efavirenz to maraviroc twice daily in patients on suppressive antiretroviral therapy

BACKGROUND

CYP3A4 induction by efavirenz (EFV) persists after drug cessation; we assessed the pharmacokinetics (PK), efficacy and safety of maraviroc (MVC) administered to HIV-infected individuals switching from EFV-containing therapy.

METHODS

Patients with R5-tropic virus and suppressed viral load on two nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) plus EFV switched EFV to MVC 600 mg twice daily for 14 days, and then to MVC 300 mg twice daily. Following screening, three intensive PK visits were performed (sampling was pre-dose and 1, 2, 4, 6, 8 and 12 h post-dose): day 1 (VISIT 1, MVC 600 mg twice daily), day 14 (VISIT 2, steady-state MVC 600 mg twice daily) and day 28 post regimen switch (VISIT 3, steady-state MVC 300 mg twice daily); MVC trough concentration (Ctrough) was determined 3, 6 and 10 days following regimen switch and viral loads up to week 24. MVC PK parameters on visits 1 and 2 and MVC Ctrough on day 6 were compared to visit 3 (reference) via geometric mean ratios (GMR) and 95% CIs.

RESULTS

Twelve males completed the study. MVC PK parameters at visit 1 versus visit 3 were: GMR and 95% CI 12-h area under the curve (AUC0-12) 1.25 (1.00, 1.58); Cmax 1.64 (1.16, 2.31); Ctrough 0.61 (0.46, 0.80). Visit 2 MVC PK parameters were significantly higher than visit 3: GMR and 95% CI AUC0-12 2.31 (1.84, 2.90); Cmax 2.42 (1.87, 3.12); Ctrough 2.25 (1.74, 2.91). MVC was well tolerated with no grade 3/4 adverse events; all subjects maintained viral suppression to the end of the study.

CONCLUSIONS

The EFV induction effect necessitated increased MVC dose to 600 mg twice daily following switch and persisted for approximately one week after EFV cessation. This is less than the 2-week induction observed when switching EFV to etravirine and highlights the importance of studying different tail interactions. Higher dose MVC was well tolerated. All measured MVC Ctrough concentrations exceeded wild-type 90% inhibitory concentration.

Impact of randomized antiretroviral therapy initiation on glucose metabolism

OBJECTIVE

Prior studies have found that early HIV protease inhibitors contribute to glucose dysregulation. Few randomized trials have evaluated glucose indices in antiretroviral-naive individuals on newer antiretroviral therapy (ART).

METHODS

A5224s was a substudy of A5202, a prospective trial of 1857 ART-naive participants randomized to blinded abacavir-lamivudine (ABC/3TC) or tenofovir DF-emtricitabine (TDF/FTC) with open-label efavirenz (EFV) or atazanavir-ritonavir (ATV/r). Analyses used two-sample t-tests, Spearman correlation coefficients and linear regression.

RESULTS

A5224s included 269 nondiabetic individuals: 85% men, 47% white non-Hispanic, baseline median age 38 years, HIV-1 RNA 4.6 log10 copies/ml and CD4 cell count 233 cells/μl. Overall, significant 96-week increases occurred in fasting glucose, insulin and the homeostatic model assessment of insulin resistance (HOMA-IR), P ≤ 0.004. Assignment to EFV (versus ATV/r) resulted in significantly greater glucose increase [mean difference 4.4; 95% confidence interval (CI) 1.3, 7.5 mg/dl; P = 0.006] but not insulin or HOMA-IR (P ≥ 0.72). Glucose indices were not significantly different between ABC/3TC and TDF/FTC arms, P ≥ 0.18. Significant correlations were detected between changes in glucose indices and changes in BMI; all r ≥ 0.23, P ≤ 0.001. In multivariable analyses, in addition to the EFV effect, higher baseline HIV-1 RNA and greater BMI change were significant independent factors associated with greater glucose increase.

CONCLUSION

Changes in glucose metabolism were not significantly different between TDF/FTC and ABC/3TC-based regimens. A small but significantly greater increase in glucose was observed in those assigned to EFV. As glucose dysregulation may increase with time on ART, longer term studies will be needed to further clarify the clinical significance of these findings.

Polymorphisms in Fas gene is associated with HIV-related lipoatrophy in Thai patients

The present study aimed to evaluate the role of genetic polymorphisms in the emergence of lipoatrophy or lipodystrophy in HIV-infected patients with antiretroviral therapy (ART) in Thailand. Position 455 upstream of the Apolipoprotein C3 gene (ApoC3 T-455C, rs2854116), codon 64 of the Beta3 adrenergic receptor gene (ARβ3 Tcod64C, rs4994), and position 670 upstream of the Fas gene (Fas A-670G, rs1800682) were genotyped in 829 HIV-infected Thai patients who had started ART. Crude and adjusted incidence rate ratios (IRR) were calculated using Poisson regression. The serum levels of cholesterol, triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) were also analyzed. Multivariate analysis revealed an association between the Fas -670AA genotype, but not the ApoC3 -455 or ARβ3 cod64 genotypes, with the incidence of lipoatrophy after adjusting for gender and stavudine (d4T)-containing regimens (IRR=1.72, 95% CI=1.20-2.45, p=0.003). However, ApoC3 -455C homozygous patients showed elevated serum levels of triglycerides, while this genotype did not affect serum total cholesterol, HDL, or LDL levels in patients with lipoatrophy or lipodystrophy. In contrast, the ARβ3 cod64 genotype did not show any significant association with the serum levels of cholesterol, triglycerides, HDL, or LDL. In conclusion, Fas -670AA affected the incidence of lipoatrophy in HIV-1-infected Thai patients, while the ApoC3 -455C allele affected the serum levels of triglycerides. These results confirmed the role of genetics in the development of ART-related metabolic disorders.

Insulin resistance and cognition among HIV-infected and HIV-uninfected adult women: the Women's Interagency HIV Study

Cognitive impairment remains prevalent in the era of combination antiretroviral therapy (cART) and may be partially due to comorbidities. We postulated that insulin resistance (IR) is negatively associated with cognitive performance. We completed a cross-sectional analysis among 1547 (1201 HIV(+)) women enrolled in the Women's Interagency HIV Study (WIHS). We evaluated the association of IR with cognitive measures among all WIHS women with concurrent fasting bloods and cognitive testing [Trails A, Trails B, and Symbol Digit Modalities Test (SDMT)] using multiple linear regression models. A smaller subgroup also completed the Stroop test (n=1036). IR was estimated using the Homeostasis Model Assessment (HOMA). Higher HOMA was associated with poorer performance on the SDMT, Stroop Color-Naming (SCN) trial, and Stroop interference trial, but remained statistically significant only for the SCN in models adjusting for important factors [β=3.78 s (95% CI: 0.48-7.08), p=0.025, for highest vs. lowest quartile of HOMA]. HIV status did not appear to substantially impact the relationship of HOMA with SCN. There was a small but statistically significant association of HOMA and reduced neuropsychological performance on the SCN test in this cohort of women.

Dietary intervention prevents dyslipidemia associated with highly active antiretroviral therapy in human immunodeficiency virus type 1-infected individuals: a randomized trial

OBJECTIVES

The purpose of this study was to evaluate the efficacy of dietary intervention on blood lipids of human immunodeficiency virus (HIV)-1-infected patients who are started on highly active antiretroviral therapy (HAART).

BACKGROUND

Current guidelines recommend diet as first-step intervention for HIV-1-infected individuals with HAART-related dyslipidemia, but there is no evidence from randomized trials to support this recommendation.

METHODS

Eighty-three HIV-1-infected patients, naive from HAART, were randomly assigned to HAART with dietary intervention (diet group, n = 43) or HAART without dietary intervention (control group, n = 40) for 12 months. Diet, according to the National Cholesterol Education Program, was given every 3 months. Before and after intervention, 24-h food records and lipid profile were obtained. Data were analyzed by intention to treat, using mixed-effects models.

RESULTS

Diet resulted in reduction of percentage of fat intake (from 31 ± 7% to 21 ± 3% of calories), while controls presented no change in percentage of fat intake. Plasma cholesterol (from 151 ± 29 mg/dl to 190 ± 33 mg/dl) and low-density lipoprotein cholesterol (from 85 ± 24 mg/dl to 106 ± 31 mg/dl) increased in the control group and were unchanged in the diet group. Plasma triglycerides were reduced by diet (from 135 ± 67 mg/dl to 101 ± 42 mg/dl) and increased in the control group (from 134 ± 70 mg/dl to 160 ± 76 mg/dl). After 1-year follow-up, 21% of patients who received diet had lipid profile compatible with dyslipidemia compared with 68% (p < 0.001) of controls.

CONCLUSIONS

Among HIV-1-positive individuals naive of previous treatment, diet prevents dyslipidemia associated with HAART. (Effect of Nutritional Intervention on the Lipid Profile of HIV-Positive Patients Who Start HAART: a Randomized Trial; NCT00429845).

Management of the metabolic effects of HIV and HIV drugs

Morphologic and metabolic abnormalities, including subcutaneous adipose tissue wasting, central adipose tissue accumulation, dyslipidemia and disorders of glucose metabolism are common among HIV-infected patients receiving highly active antiretroviral therapy (HAART) and contribute to the risk of cardiovascular disease in this population. The pathogenesis of these disorders is due to complicated interactions between effects of chronic HIV infection, HAART medications and patient factors, including genetic susceptibility. HAART has transformed HIV into a chronic condition for many patients and as a result the majority of HIV-infected patients in many areas of the developed world will soon be aged ≥50 years. Given that metabolic and cardiovascular diseases increase with aging, knowledge of the optimal management of these conditions is essential for practitioners caring for HIV-infected patients, including endocrine subspecialists. This Review highlights the clinical management of these disorders, focusing on the latest evidence regarding the efficacy of treatment strategies, newly available medications and potential interactions between HAART medications and medications used to treat metabolic disorders.

Management of dyslipidemia in HIV-infected patients

Antiretroviral therapy has dramatically increased survival for HIV-infected individuals. As this population lives longer, coronary heart disease has become an important comorbid condition. Dyslipidemia in HIV-infected individuals is a complex condition, with multiple contributing factors including the HIV virus itself, individual genetic characteristics and antiretroviral therapy-induced metabolic changes. Effective management of dyslipidemia in this population is essential to reduce cardiovascular risk but presents multiple challenges due to interactions between antiretroviral therapy agents and lipid-lowering medications.

Added value of deep sequencing relative to population sequencing in heavily pre-treated HIV-1-infected subjects

OBJECTIVE

To explore the potential of deep HIV-1 sequencing for adding clinically relevant information relative to viral population sequencing in heavily pre-treated HIV-1-infected subjects.

METHODS

In a proof-of-concept study, deep sequencing was compared to population sequencing in HIV-1-infected individuals with previous triple-class virological failure who also developed virologic failure to deep salvage therapy including, at least, darunavir, tipranavir, etravirine or raltegravir. Viral susceptibility was inferred before salvage therapy initiation and at virological failure using deep and population sequencing genotypes interpreted with the HIVdb, Rega and ANRS algorithms. The threshold level for mutant detection with deep sequencing was 1%.

RESULTS

7 subjects with previous exposure to a median of 15 antiretrovirals during a median of 13 years were included. Deep salvage therapy included darunavir, tipranavir, etravirine or raltegravir in 4, 2, 2 and 5 subjects, respectively. Self-reported treatment adherence was adequate in 4 and partial in 2; one individual underwent treatment interruption during follow-up. Deep sequencing detected all mutations found by population sequencing and identified additional resistance mutations in all but one individual, predominantly after virological failure to deep salvage therapy. Additional genotypic information led to consistent decreases in predicted susceptibility to etravirine, efavirenz, nucleoside reverse transcriptase inhibitors and indinavir in 2, 1, 2 and 1 subject, respectively. Deep sequencing data did not consistently modify the susceptibility predictions achieved with population sequencing for darunavir, tipranavir or raltegravir.

CONCLUSIONS

In this subset of heavily pre-treated individuals, deep sequencing improved the assessment of genotypic resistance to etravirine, but did not consistently provide additional information on darunavir, tipranavir or raltegravir susceptibility. These data may inform the design of future studies addressing the clinical value of minority drug-resistant variants in treatment-experienced subjects.

Pathogenesis and treatment of HIV lipohypertrophy

PURPOSE OF REVIEW

This review addresses our current understanding of the pathogenesis of HIV-associated lipohypertrophy and describes an evidence-based approach to treatment.

RECENT FINDINGS

Although the pathogenesis of HIV-associated lipohypertrophy remains elusive, recent clinical and laboratory investigations in fatty acid metabolism and growth hormone dynamics have furthered our understanding of the condition. These findings have also paved the way for new therapeutic interventions, of which tesamorelin, an analog of growth hormone-releasing hormone (GHRH), has gained recognition as a promising treatment strategy against visceral fat accumulation. Recent randomized placebo-controlled trials of tesamorelin demonstrated significant reductions in visceral adipose tissue, improvement in lipid parameters, and minimal adverse effects on glucose tolerance. Optimal therapeutic dosing and treatment duration, though, are not yet known. Whether treatment with GHRH-analogs will translate into improved long-term metabolic and cardiovascular outcomes also remains to be seen.

SUMMARY

Although the pathogenesis of HIV lipohypertrophy remains unclear, several theories and observations have led to the development of treatment strategies to counter fat accumulation and its accompanying metabolic complications. Based on clinical trials, analogs of the growth hormone (GH)/GHRH axis appear to be most effective in reducing visceral adipose tissue.

Change in high-sensitivity c-reactive protein levels following initiation of efavirenz-based antiretroviral regimens in HIV-infected individuals

Elevations in C-reactive protein (CRP) are associated with increased cardiovascular disease (CVD) risk, increased HIV disease progression, and death in HIV-infected patients. Use of abacavir has been reported to increase CVD risk. We assessed the effect of virologically suppressive efavirenz (EFV)-based antiretroviral therapy on high sensitivity CRP (hsCRP) levels over a 96-week period with particular attention to the effect of gender and abacavir use. Banked sera from entry and week 96 visits of AIDS Clinical Trials Group A5095 participants were assayed for hsCRP, then analyzed by gender, abacavir randomization, and for correlation with changes in fasting metabolic parameters. Analyses of hsCRP were conducted in two phases and involved a total of 145 men and 51 women. hsCRP did not differ by gender at baseline but higher levels were seen at week 96 in women (median 6 mg/liter; Q1, Q3, 1.8, 13.8) compared to men (median 1.6 mg/liter; Q1, Q3, 0.9, 4.2, p < 0.001), with an estimated shift in hsCRP by gender of 2.5 mg/liter (95% CI 1.0, 5.1). There was no difference in hsCRP levels by abacavir use. Changes in hsCRP did not correlate with changes in insulin resistance or with changes in fasting lipids. Durably virologically suppressive therapy with EFV-based regimens did not decrease hsCRP levels over a 96-week period. hsCRP levels increased significantly only in women. Randomization to abacavir had no effect on changes in hsCRP levels. Changes in hsCRP levels did not correlate with changes in fasting metabolic parameters.

Switching antiretroviral therapy to minimize metabolic complications

Advances in HIV therapy have made living with HIV for decades a reality for many patients. However, antiretroviral therapy has been associated with multiple long-term complications, including dyslipidemia, fat redistribution, insulin resistance and increased cardiovascular risk. As newer agents with improved metabolic profiles have become available, there is growing interest in the safety and efficacy of switching ART as a strategy to reduce long-term complications. This article reviews recently published data on switching ART to minimize the contributions of specific agents to these complications.

An update on the use of Atripla in the treatment of HIV in the United States

Atripla^® (Gilead Sciences Inc, Foster City, CA, USA and Bristol-Myers Squibb, New York City, NY, USA) is a coformulated single pill composed of efavirenz, emtricitabine, and tenofovir disoproxil, intended as a once-daily potent combination antiretroviral therapeutic agent. Its efficacy is equivalent to the 3 component drugs taken in a combination as single medications. The coformulated antiretroviral regimen can be quite effective in patients whose human immunodeficiency virus is sensitive to all 3 components of Atripla. However, women at risk of pregnancy, already pregnant, or nursing mothers should not take Atripla, due to the teratogenic potential of the efavirenz moiety. Adverse effects are similar to those seen with the constituent medications, including potential central nervous system effects and renal toxicity. Since its US Food and Drug administration approval, prescriptions for Atripla have increased steadily.

Lipid profiles in HIV-infected adults receiving atazanavir and atazanavir/ritonavir: systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

To compare lipid profiles in HIV-infected adults receiving atazanavir-based regimens.

METHODS

We conducted a systematic review of randomized controlled trials (RCTs) comparing atazanavir or atazanavir/ritonavir with a comparator and evaluated lipids at 48 weeks. We searched MEDLINE, EMBASE, CENTRAL, LILACS, Current Controlled Trials, National Institutes of Health Clinical Trials Registry, trials at AIDSinfo and HIV conference proceedings to May 2009. Standardized mean difference (SMD) between study arms in change from baseline to week 48 in lipid parameters was determined weighted by study size and 95% confidence intervals (CI) were calculated.

RESULTS

Nine eligible RCTs were identified (n = 3346). SMDs (mmol/L) in four RCTs comparing atazanavir/ritonavir with a ritonavir-boosted protease inhibitor were: total cholesterol, -0.62 (95% CI -0.72, -0.51); low-density lipoprotein (LDL) cholesterol, -0.31 (95% CI -0.44, -0.17); high-density lipoprotein (HDL) cholesterol, -0.16 (95% CI -0.27, -0.06); non-HDL cholesterol, -0.58 (95% CI -0.69, -0.48); and triglycerides, -0.46 (95% CI -0.58, -0.34). Atazanavir compared with non-atazanavir (three RCTs) found lower total, LDL and non-HDL cholesterol, and triglycerides [SMD -0.87 mmol/L (95% CI -0.99, -0.76); -0.56 mmol/L (95% CI -0.67, -0.45); -0.88 mmol/L (95% CI -0.99, -0.76); and -0.56 mmol/L (95% CI -0.75, -0.36), respectively], but HDL cholesterol did not differ [-0.16 mmol/L (95% CI -0.49, 0.16)]. In the atazanavir/ritonavir versus atazanavir comparison (two RCTs), total [SMD 0.44 mmol/L (95% CI 0.23, 0.65)] and non-HDL cholesterol [SMD 0.44 mmol/L (95% CI 0.23, 0.65)] were higher, but HDL cholesterol, LDL cholesterol and triglycerides were not different.

CONCLUSIONS

At 48 weeks, plasma lipid concentrations were lower with atazanavir/ritonavir than with other ritonavir-boosted protease inhibitor regimens. Total and non-HDL cholesterol were higher with atazanavir/ritonavir than atazanavir alone.

Abacavir/lamivudine fixed-dose combination antiretroviral therapy for the treatment of HIV

In the past 15 years, improvements in the treatment of HIV infection have dramatically reduced morbidity and mortality. Nucleoside reverse transcriptase inhibitors are the backbone of combination antiretroviral therapy for the treatment of HIV. One of the recommended and commonly used therapies in this class is the once-daily fixed-dose combination of abacavir/lamivudine. Clinical studies and practice have shown these drugs to be potent, safe, and easy to use in a variety of settings; however, several recent reports have challenged the safety and efficacy claims among certain patient populations, including those at risk for cardiovascular disease and in those with high viral loads prior to treatment initiation. We reviewed abacavir/lamivudine as a treatment for HIV and discussed limitations of its use due to these controversial issues.

Human immunodeficiency virus and highly active antiretroviral therapy-associated metabolic disorders and risk factors for cardiovascular disease

The successful introduction of highly active antiretroviral therapy (HAART), a combination of potent antiretroviral agents, including protease inhibitors, nucleoside reverse transcriptase inhibitors, and nonnucleoside reverse transcriptase inhibitors, has impacted positively on morbidity and mortality among human immunodeficiency virus (HIV)-positive patients. Over time, HAART has been associated with a number of metabolic and anthropometric abnormalities, including dyslipidemia and insulin resistance as well as subcutaneous fat loss and abdominal obesity, potentially contributing to cardiovascular risk. Recent studies have more firmly established that both HIV infection and HAART might increase the risk of clinical cardiovascular events. Furthermore, whereas HIV/HAART is associated with multiple aspects of endocrine dysfunction, there has been less focus on bone disease, although some studies indicate a higher prevalence of osteoporosis among HIV-positive subjects compared to HIV-negative controls. The relationship between bone and fat metabolism under HIV-positive conditions deserves further attention, and available data suggest the possibility of an intriguing connection. In the future, an increasing population of aging HIV-positive patients with a spectrum of antiretroviral therapies and accumulation of endocrine abnormalities and conventional cardiovascular risk factors will present preventive and therapeutic challenges to our health-care system.

Antiretroviral therapy and cardiovascular risk: are some medications cardioprotective?

PURPOSE OF REVIEW

This review addresses the associations between coronary heart disease and antiretroviral medications, with a specific focus on medications that appear to have neutral or positive effects on coronary heart disease risk factors.

RECENT FINDINGS

Studies have linked combination antiretroviral therapy with an increased risk of coronary heart disease. Often implicated are the effects of these medications on the metabolic risk factors for coronary heart disease, specifically lipids and glucose homeostasis. Many newer antiretrovirals have fewer metabolic side effects, and antiretrovirals in general may be cardioprotective by reducing inflammation. Whether use of specific antiretroviral regimens will translate into improved cardiovascular outcomes remains to be seen.

SUMMARY

Some antiretrovirals appear to be at least neutral with regards to coronary heart disease risk, but it is not clear if any are truly cardioprotective. Nonetheless, it is prudent to consider regimens with limited metabolic side effects in patients with pre-established coronary heart disease risk.

Evaluation of IGF-2/ApaI polymorphism in pregnant women infected with human immunodeficiency virus type 1 taking antiretroviral drugs

OBJECTIVE

Studies carried out to assess the effects of antiretroviral drugs (ARV) in HIV-1 infected pregnant women have demonstrated carbohydrate intolerance. Some reports also refer to the effect of disturbances in the expression of the insulin-like growth factor (IGF) system on pancreas beta-cell function in humans and IGF-2/ApaI polymorphisms have been associated with obesity and features of the metabolic syndromes. In the present study, we tested the association between IGF-2/ApaI genotype and hyperglycemia in HIV-1 infected pregnant women receiving ARV.

DESIGN

We studied IGF-2/ApaI polymorphism in 87 healthy pregnant women, 43 HIV-1 infected pregnant women taking ARV with hyperglycemia during pregnancy, and 43 HIV-1-negative pregnant women with gestational diabetes. Blood samples were obtained for DNA extraction, PCR and genotyping. Data were analyzed statistically by the Kolmogorov-Smirnov normality, ANOVA and chi-square tests.

RESULTS

There were no significant differences in genotype frequency among the three groups analyzed. Considering the HIV-1-infected pregnant women, there were no significant differences in genotype frequency between the zidovudine group and the triple antiretroviral treatment group. There were no significant differences in allele frequencies among the groups evaluated. Non-white pregnant women tended to present the GG genotypes compared to white pregnant women.

CONCLUSION

These results contribute to a better understanding of metabolic glycemic disorders in HIV-1-infected pregnant women using ARV, showing that IGF-2/ApaI polymorphisms are not responsible as a single causative factor of glycemic alterations. These data indicate that other variables should be studied in order to explain these glycemic abnormalities.

Efavirenz: a decade of clinical experience in the treatment of HIV

Efavirenz, a non-nucleoside reverse transcriptase inhibitor, has been an important component of the treatment of HIV infection for 10 years and has contributed significantly to the evolution of highly active antiretroviral therapy (HAART). The efficacy of efavirenz has been established in numerous randomized trials and observational studies in HAART-naive patients, including those with advanced infection. In the ACTG A5142 study, efavirenz showed greater virological efficacy than the boosted protease inhibitor (PI), lopinavir. Efavirenz is more effective as a third agent than unboosted PIs or the nucleoside analogue abacavir. Some, but not all, studies have suggested that efavirenz (added to two nucleoside reverse transcriptase inhibitors) is more effective than nevirapine. Virological and immunological responses achieved with efavirenz-based HAART have been maintained for 7 years. Dosing convenience predicts adherence, and studies have demonstrated that patients can be switched from PI-based therapy to simplified, once-daily efavirenz-based regimens without losing virological control. The one-pill, once-daily formulation of efavirenz plus tenofovir and emtricitabine offers a particular advantage in this regard. Efavirenz also retains a role after failure of a first PI-based regimen. Efavirenz is generally well tolerated: rash and neuropsychiatric disturbances are the most notable adverse events. Neuropsychiatric disturbances generally develop early in treatment and they tend to resolve with continued administration, but they are persistent and troubling in a minority of patients. Efavirenz has less effect on plasma lipid profiles than some boosted PIs. Lipodystrophy can occur under treatment with efavirenz but it may be reduced if the concurrent use of thymidine analogues is avoided. Efavirenz resistance mutations (especially K103N) can be selected during long-term treatment, underscoring the importance of good adherence. Recent data have confirmed that efavirenz is a cost-effective option for first-line HAART. In light of these features, efavirenz retains a key role in HIV treatment strategies and is the first-line agent recommended in some guidelines.

Metabolic outcomes in a randomized trial of nucleoside, nonnucleoside and protease inhibitor-sparing regimens for initial HIV treatment

BACKGROUND

The metabolic effects of initial therapy for HIV-1 infection are important determinants of regimen selection.

METHODS

Open-label study in 753 subjects randomized equally to efavirenz or lopinavir/ritonavir(r) plus two nucleoside reverse-transcriptase inhibitor (NRTI) vs. the NRTI-sparing regimen of lopinavir/r plus efavirenz. Zidovudine, stavudine, or tenofovir with lamivudine was selected prior to randomization. Metabolic outcomes through 96 weeks were lipoatrophy, defined as at least 20% loss in extremity fat, and fasting serum lipids.

RESULTS

Lipoatrophy by dual-energy X-ray absorptiometry at week 96 occurred in 32% [95% confidence interval (CI) 25-39%] of subjects in the efavirenz plus two NRTIs arm, 17% (95% CI 12-24) in the lopinavir/r plus two NRTIs arm, and 9% (95% CI 5-14) in the NRTI-sparing arm (P < or = 0.023 for all comparisons). Varying the definition of lipoatrophy (> or =10 to > or =40% fat loss) and correction for baseline risk factors did not affect the significant difference in lipoatrophy between the NRTI-containing regimens. Lipoatrophy was most frequent with stavudine-containing regimens and least frequent with tenofovir-containing regimens (P < 0.001), which were not significantly different from the NRTI-sparing regimen. Total cholesterol increases at week 96 were greatest in the NRTI-sparing arm (median +57 mg/dl) compared with the other two arms (+32-33 mg/dl; P < 0.001). Use of lipid-lowering agents was more common (25 vs. 11-13%) in the NRTI-sparing arm.

CONCLUSION

Lipoatrophy was more frequent with efavirenz than lopinavir/r when combined with stavudine or zidovudine, and less frequent when either drug was combined with tenofovir. Lipoatrophy was least frequent with the NRTI-sparing regimen, but this benefit was offset by greater cholesterol elevations and the need for lipid-lowering agents.

Cardiovascular complications in HIV management: past, present, and future

Highly active antiretroviral therapy (HAART) has significantly improved the prognosis for many individuals with HIV infection. Consequently, HIV infection has become a chronic and manageable disease. The focus on long-term management of patients with HIV infection has broadened to include comorbid conditions, most notably cardiovascular disease. Patients with HIV infection share many cardiovascular risk factors with the general population, and HIV infection itself may increase cardiovascular risk. Changes in lipid profiles associated with increased cardiovascular risk that have been observed with some HAART regimens have been a cause for concern among clinicians who treat HIV-infected patients. However, the lipid effects of HAART seem to depend on the type and duration of regimens employed. They can be managed effectively according to current guidelines that recommend lifestyle changes (eg, improved diet, increased exercise, smoking cessation) and pharmacologic therapy described in established treatment paradigms for patients on antiretroviral therapy and similar to measures currently used by the general population. A review of the clinical data indicates that the virologic and immunologic benefits of HAART clearly outweigh any metabolic effects observed in some patients over time and that preexisting, established cardiovascular risk factors contribute significantly to the potential development of cardiovascular events. These benefits of antiretroviral therapy have been demonstrated in studies comparing the superior efficacy of continuous vs. intermittent HAART.

Racial differences in changes of metabolic parameters and body composition in antiretroviral therapy-naive persons initiating antiretroviral therapy

OBJECTIVE

To assess by race/ethnicity long-term changes in metabolic parameters and body composition among treatment-naive persons initiating antiretroviral therapy (ART).

METHODS

We compared changes in 398 participants (African American n = 243, Latino n = 43, white n = 112) initiating ART. At baseline, 1-month (metabolic parameters only) and 4-month follow-up intervals (anthropometric measurements) were performed and fasting metabolic parameters measured. Rates of change over time and overall mean changes from baseline were compared.

RESULTS

Latinos had the greatest increase in glucose and insulin resistance and greatest loss of mid-arm and mid-thigh subcutaneous tissue areas. On average, mid-arm and mid-thigh nonsubcutaneous tissue areas increased in all races. Waist subcutaneous tissue area decreased only for Latinos. Visceral tissue area increased the most for Latinos and whites. For all groups, the initial increase in high-density lipoprotein cholesterol was sustained. The initial increase in low-density lipoprotein cholesterol was followed by a gradual decline in all groups. Triglycerides increased for all groups; the increase being the least for African Americans.

CONCLUSIONS

In this prospective long-term evaluation, changes in metabolic parameters and body composition varied across race groups. Latinos experienced the most unfavorable changes. Such changes should be monitored over time as the identified differences may impact ART selection.

A randomized, controlled trial of initial anti-retroviral therapy with abacavir/lamivudine/zidovudine twice-daily compared to atazanavir once-daily with lamivudine/zidovudine twice-daily in HIV-infected patients over 48 weeks (ESS100327, the ACTION Study)

Background

Traditional first line regimens containing a non-nucleoside reverse transcriptase inhibitor or protease inhibitor may not be suitable for a subset of antiretroviral-naïve patients such as those with certain co-morbidities, women of child-bearing potential, and intolerability to components of standard first line therapy. This study was conducted to determine if alternate treatment options may meet the needs of both general and special patient populations. The ACTION study was a randomized, open-label, multicenter, 48-week trial that compared the safety and efficacy of a triple nucleoside regimen versus a protease inhibitor plus a dual nucleoside regimen in HIV-1 treatment-naïve subjects.

Results

279 HIV-infected subjects with HIV-1 RNA (VL) >5000 but < 200,000 copies/mL (c/mL) and CD4+ count ≥ 100 cells/mm³ were randomized (1:1) to receive abacavir sulfate/lamivudine/zidovudine (ABC/3TC/ZDV) twice-daily or atazanavir (ATV) once-daily plus lamivudine/zidovudine (3TC/ZDV) twice-daily. Protocol-defined virologic failure was based on multiple failure criteria.

Non-inferiority of ABC/3TC/ZDV to ATV+3TC/ZDV was established with 62% vs. 59% of subjects achieving a VL < 50 c/mL at week 48, [ITT(E), M/S = F, 95% CI: -5.9, 10.4]. Similar results were observed in the 230 (82%) subjects with baseline VL<100,000 c/mL (ABC/3TC/ZDV vs. ATV+3TC/ZDV), 66% vs. 59%; 95% CI: -5.6, 19.5. However, ABC/3TC/ZDV did not meet the non-inferiority criterion compared to ATV+3TC/ZDV in the 48 subjects with baseline VL ≥ 100,000 c/mL, 39% vs. 60%; 95% CI: -49.2, 7.4, respectively. Protocol-defined virologic failure was similar between groups.

Conclusion

ABC/3TC/ZDV demonstrated comparable virologic efficacy to ATV+3TC/ZDV in this population over 48 weeks. In those with a baseline VL ≥ 100,000 c/mL, subjects in the ATV+3TC/ZDV showed better virologic efficacy. Both regimens offer benefits in select therapy-naïve subjects.

Trial Registration

[Clinical Trials Identifier, NCT00082394].

Long-term evaluation of glucose homeostasis in a cohort of HAART-treated HIV-infected children: a longitudinal, observational cohort study

BACKGROUND AND OBJECTIVES

Few and mainly cross-sectional studies of glucose homeostasis are available in HIV-infected children treated with highly active antiretroviral therapy (HAART). The aim of the present study was to describe a 4-year course of glucose homeostasis in a cohort of HAART-treated children and adolescents, using glucose and insulin levels during an oral glucose tolerance test (OGTT) as outcome measures. In addition, we investigated possible risk factors, both related and unrelated to antiretroviral therapy, associated with insulin resistance.

METHODS

We assessed glucose metabolism yearly for 4 consecutive years in 37 HIV-infected children receiving a protease inhibitor (PI)-based HAART regimen containing lamivudine/stavudine plus indinavir or ritonavir or nelfinavir or a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based HAART regimen containing lamivudine/tenofovir/efavirenz. Generalized estimating equations were used to evaluate the relationship between the loge-transformed area under the serum concentration-time curve (AUC) of insulin during OGTT and antiretroviral therapy, controlling for time, sex, baseline age, puberty, body mass index and CD4+ T cells percentage.

RESULTS

Ritonavir-unboosted PI-based HAART regimens were administered to most children at baseline; however, their use decreased during follow-up in favour of an NNRTI-based regimen. The nelfinavir/lamivudine/stavudine (regression coefficient=-0.69, p<0.05) and efavirenz/lamivudine/tenofovir (regression coefficient=-0.93, p<0.05) regimens, but not the ritonavir/lamivudine/stavudine regimen, were negatively associated with loge-transformed insulin AUC compared with indinavir/lamivudine/stavudine. Puberty was positively associated with loge-transformed insulin AUC.

CONCLUSIONS

This 4-year prospective study of HAART-treated HIV-infected children shows that: (i) the nelfinavir/lamivudine/stavudine and the efavirenz/lamivudine/tenofovir regimens but not the ritonavir/lamivudine/stavudine regimen were associated with higher insulin sensivity, i.e. lower insulin AUC, compared with indinavir/lamivudine/stavudine; (ii) the treatment switched substantially in favour of NNRTI from the third year on and this change was associated with an improvement in insulin sensitivity compared with the previous HAART-based regimens; and (iii) puberty is a primary determinant of insulin sensitivity.

Lipoprotein Changes in HIV-Infected Antiretroviral-Naïve Individuals after Starting Antiretroviral Therapy: ACTG Study A5152s Stein: Lipoprotein Changes on Antiretroviral Therapy

BACKGROUND: Dyslipidemia is a frequent complication of antiretroviral therapy (ART) for patients with human immunodeficiency virus infection (HIV). The effects of ART on lipoproteins are less well-understood, and have not been investigated in a prospective study where assignment to ART is randomized. OBJECTIVE: To evaluate the effects of three class-sparing ART regimens on lipids and lipoproteins. METHODS: This was a substudy of a prospective, multicenter study treatment-naïve HIV-infected individuals randomly assigned to receive a regimen of nucleoside reverse transcriptase inhibitors (NRTIs) + the non-nucleoside reverse transcriptase inhibitor efavirenz, NRTIs + the protease inhibitor lopinavir/ritonavir, or a NRTI-sparing regimen of efavirenz + lopinavir/ritonavir. Lipoproteins were measured by nuclear magnetic resonance spectroscopy. RESULTS: Among the 82 participants, total and small low-density lipoprotein concentrations increased (median, interquartile range) by 152 (-49 - +407, p<0.01) and 130 (-98 - +417, p<0.01) nmol/L, respectively, especially in the arms containing lopinavir/ritonavir (p(KW)<0.04). Very low-density lipoproteins also increased (p<0.01), with a larger increase in the arms that contained lopinavir/ritonavir (p=0.022). High-density lipoproteins increased by 6.0 nmol/L (2.8 - 10.4, p<0.01), but differences between arms were not significant (p(KW)=0.069). Changes were not related to changes in markers of insulin/glucose metabolism. CONCLUSIONS: Total and small low-density lipoprotein concentrations increased, especially in the arms containing lopinavir/ritonavir, as did increases in total very low-density lipoproteins. Adverse changes were especially prominent in the arm with efavirenz + lopinavir/ritonavir.