Panel de expertos de Gesida y Plan Nacional sobre el Sida. [Consensus document of Gesida and Spanish Secretariat for the National Plan on AIDS (SPNS) regarding combined antiretroviral treatment in adults infected by the human immunodeficiency virus (January 2012)]

Significance and clinical management of persistent low-level viremia and very-low-level viremia in HIV-1-infected patients

A goal of HIV therapy is to sustain suppression of the plasma viral load below the detection limits of clinical assays. However, widely followed treatment guidelines diverge in their interpretation and recommended management of persistent viremia of low magnitude, reflecting the limited evidence base for this common clinical finding. Here, we review the incidence, risk factors, and potential consequences of low-level HIV viremia (LLV; defined in this review as a viremia level of 50 to 500 copies/ml) and very-low-level viremia (VLLV; defined as a viremia level of <50 copies/ml detected by clinical assays that have quantification cutoffs of <50 copies/ml). Using this framework, we discuss practical issues related to the diagnosis and management of patients experiencing persistent LLV and VLLV. Compared to viral suppression at <50 or 40 copies/ml, persistent LLV is associated with increased risk of antiretroviral drug resistance and overt virologic failure. Higher immune activation and HIV transmission may be additional undesirable consequences in this population. It is uncertain whether LLV of <200 copies/ml confers independent risks, as this level of viremia may reflect assay-dependent artifacts or biologically meaningful events during suppression. Resistance genotyping should be considered in patients with persistent LLV when feasible, and treatment should be modified if resistance is detected. There is a dearth of clinical evidence to guide management when genotyping is not feasible. Increased availability of genotypic assays for samples with viral loads of <400 copies/ml is needed.

Durability of the first antiretroviral treatment regimen and reasons for change in patients with HIV infection

BACKGROUND

To study the durability of the drugs and coformulations currently used in the first treatment regimen of antiretroviral therapy (ART) for HIV patients, and to examine the reasons for changing this medication.

METHODS

A retrospective observational multicenter study of patients with HIV infection who started a first-line ART regimen between January 2007 and June 2010. The primary outcome variable was the durability of this first ART regimen until discontinued or amended and the reasons for the change. Survival analysis of durability was performed using Kaplan-Meyer curves analysis, and a Cox multiple regression model was constructed to identify associated factors.

RESULTS

A first-line ART regimen was initiated for 600 patients; after 1 year, it had been changed in 172 (28%) cases, with a median duration of 31 months. The main reason for change was toxicity (20.5% of all patients), followed by loss to follow-up (8.3%) and virological failure (5.3%). The most common type of toxicity was gastrointestinal (30%), followed by cutaneous (23%) and neuropsychiatric (18%). The use of non-nucleoside reverse transcriptase inhibitors (NNRTIs) was associated with greater durability than that of protease inhibitors (43 months vs 21 months; P = .001).

CONCLUSIONS

The durability of the first-line ART regimen, based on current antiretroviral drugs and coformulations, is about 2.5 years, with toxicity being the main reason for its modification. Gastrointestinal toxicity is the type most commonly reported. NNRTI treatment is associated with greater durability of the first treatment regimen.

Reduced sTWEAK and increased sCD163 levels in HIV-infected patients: modulation by antiretroviral treatment, HIV replication and HCV co-infection

Background

Patients infected with the human immunodeficiency virus (HIV) have an increased risk of cardiovascular disease due to increased inflammation and persistent immune activation. CD163 is a macrophage scavenger receptor that is involved in monocyte-macrophage activation in HIV-infected patients. CD163 interacts with TWEAK, a member of the TNF superfamily. Circulating levels of sTWEAK and sCD163 have been previously associated with cardiovascular disease, but no previous studies have fully analyzed their association with HIV.

Objective

The aim of this study was to analyze circulating levels of sTWEAK and sCD163 as well as other known markers of inflammation (hsCRP, IL-6 and sTNFRII) and endothelial dysfunction (sVCAM-1 and ADMA) in 26 patients with HIV before and after 48 weeks of antiretroviral treatment (ART) and 23 healthy subjects.

Results

Patients with HIV had reduced sTWEAK levels and increased sCD163, sVCAM-1, ADMA, hsCRP, IL-6 and sTNFRII plasma concentrations, as well as increased sCD163/sTWEAK ratio, compared with healthy subjects. Antiretroviral treatment significantly reduced the concentrations of sCD163, sVCAM-1, hsCRP and sTNFRII, although they remained elevated when compared with healthy subjects. Antiretroviral treatment had no effect on the concentrations of ADMA and sTWEAK, biomarkers associated with endothelial function. The use of protease inhibitors as part of antiretroviral therapy and the presence of HCV-HIV co-infection and/or active HIV replication attenuated the ART-mediated decrease in sCD163 plasma concentrations.

Conclusion

HIV-infected patients showed a proatherogenic profile characterized by increased inflammatory, immune-activation and endothelial-dysfunction biomarkers that partially improved after ART. HCV-HIV co-infection and/or active HIV replication enhanced immune activation despite ART.

Effectiveness of efavirenz compared with ritonavir-boosted protease-inhibitor-based regimens as initial therapy for patients with plasma HIV-1 RNA above 100,000 copies/ml

BACKGROUND

There are no clinical trials in which the main objective is to compare the efficacy of efavirenz versus ritonavir-boosted protease inhibitor (PI/r)-based initial antiretroviral therapy (ART) in patients with high plasma HIV-1 RNA levels. This study aims to compare these regimens in this patient population in the setting of routine clinical practice.

METHODS

This was a multicentre, observational cohort study, including 596 consecutive treatment-naive patients with plasma HIV-1 RNA>100,000 copies/ml initiating efavirenz or PI/r-based ART between 2000 and 2010. The primary effectiveness end point was the percentage of patients with HIV-1 RNA<50 copies/ml at week 48 by intent-to-treat analysis.

RESULTS

Among a total of 596 patients, 57% initiated efavirenz and 43% PI/r-regimens (73% lopinavir and fosamprenavir [62% lopinavir, 11% fosamprenavir]). HIV-1 RNA suppression to <50 copies/ml at week 48 was higher in the efavirenz group (84% versus 74% [difference 10%, 95% CI 3.4%, 16.7%; P=0.002]). The percentage of virological failures was similar (efavirenz 4% versus PI/r 4%; P=0.686), but voluntary discontinuations and toxicity-related treatment changes were higher with PI/r (4% versus 1%; P=0.006 and 11% versus 6%; P=0.069, respectively). However, resistance selection at failure was higher in patients receiving efavirenz (89% versus 50%; P=0.203). Efavirenz was significantly more effective than lopinavir/r or fosamprenavir/r, whereas no significant differences were observed between efavirenz and darunavir/r or atazanavir/r. The high viral suppression in the efavirenz group was also evident in patients with very high viral loads (>500,000 copies/ml) and in those with low CD4(+) T-cell counts.

CONCLUSIONS

In routine clinical practice, the effectiveness of initial efavirenz-based regimens was at least similar to or even higher than various PI/r-based regimens in HIV-1-infected patients with plasma HIV-1 RNA>100,000 copies/ml.

[Consensus Statement by GeSIDA/National AIDS Plan Secretariat on antiretroviral treatment in adults infected by the human immunodeficiency virus (Updated January 2013)]

OBJECTIVE

This consensus document is an update of combined antiretroviral therapy (cART) guidelines for HIV-1 infected adult patients.

METHODS

To formulate these recommendations a panel composed of members of the GeSIDA/National AIDS Plan Secretariat (Grupo de Estudio de Sida and the Secretaría del Plan Nacional sobre el Sida) reviewed the efficacy and safety advances in clinical trials, cohort and pharmacokinetic studies published in medical journals (PubMed and Embase) or presented in medical scientific meetings. The strength of the recommendations and the evidence which support them are based on a modification of the criteria of Infectious Diseases Society of America.

RESULTS

cART is recommended in patients with symptoms of HIV infection, in pregnant women, in serodiscordant couples with high risk of transmission, in hepatitisB co-infection requiring treatment, and in HIV nephropathy. cART is recommended in asymptomatic patients if CD4 is <500cells/μl. If CD4 are >500cells/μl cART should be considered in the case of chronic hepatitisC, cirrhosis, high cardiovascular risk, plasma viral load >100.000 copies/ml, proportion of CD4 cells <14%, neurocognitive deficits, and in people aged >55years. The objective of cART is to achieve an undetectable viral load. The first cART should include 2 reverse transcriptase inhibitors (RTI) nucleoside analogs and a third drug (a non-analog RTI, a ritonavir boosted protease inhibitor, or an integrase inhibitor). The panel has consensually selected some drug combinations, for the first cART and specific criteria for cART in acute HIV infection, in tuberculosis and other HIV related opportunistic infections, for the women and in pregnancy, in hepatitisB or C co-infection, in HIV-2 infection, and in post-exposure prophylaxis.

CONCLUSIONS

These new guidelines update previous recommendations related to first cART (when to begin and what drugs should be used), how to monitor, and what to do in case of viral failure or adverse drug reactions. cART specific criteria in comorbid patients and special situations are similarly updated.

[Initial antiretroviral treatment in human immunodeficiency virus-infected patients in Spain: Decisions made in relation to particular immunovirological characteristics (PERFIL-es study)]

INTRODUCTION

The purpose of Perfil-es study was to identify the proportion of patients starting ARV treatment based on NNRTIs or PI/r, and to identify the variables involved in the therapeutic decision-making in standard clinical practice.

METHODS

An observational retrospective study performed in 65 Spanish hospitals.

RESULTS

Was a total of 1,687 starts: 53% with NNRTI-based regimen and 42% with PI/r, and of the 642 patients analyzed, 72% had a CD4 count<350 cells/μl.

CONCLUSION

The initiation of ARV treatment is still late in Spain. NNRTIs are the more frequent choice, although PI/r plays an important role.

Atazanavir-bilirubin interaction: a pharmacokinetic-pharmacodynamic model

Purpose

The aim of this work was to analyze the atazanavir–bilirubin relationship, using a new mathematical approach to pharmacokinetic–pharmacodynamic models, for competitive drug interactions based on Michaelis–Menten equations.

Patients and methods

Because atazanavir induces an increase of plasma bilirubin levels, in a concentration-dependent manner, we developed a mathematical model, based on increments of atazanavir and bilirubin concentrations at steady state, in HIV infected (HIV⁺) patients, and plotted the corresponding nomogram for detecting suboptimal atazanavir exposure.

Results

By applying the obtained model, the results indicate that an absolute value or an increment of bilirubin at steady state below 3.8 μmol/L, are predictive of suboptimal atazanavir exposure and therapeutic failure.

Conclusion

We have successfully implemented a new mathematical approach to pharmacokinetic–pharmacodynamic model for atazanavir–bilirubin interaction. As a result, we found that bilirubin plasma levels constitute a good marker of exposure to atazanavir and of viral suppression.

Virological efficacy in cerebrospinal fluid and neurocognitive status in patients with long-term monotherapy based on lopinavir/ritonavir: an exploratory study

BACKGROUND

Data on suppression of HIV replication in the CNS and on the subsequent risk of neurocognitive impairment using monotherapy with boosted protease inhibitors are limited.

METHODS

Ours was an exploratory cross-sectional study in patients on lopinavir/ritonavir-based monotherapy (LPV/r-MT) or standard triple therapy (LPV/r-ART) for at least 96 weeks who maintained a plasma viral load <50 copies/mL. HIV-1 RNA in CSF was determined by HIV-1 SuperLow assay (lower limit of detection, 1 copy/mL). Neurocognitive functioning was assessed using a recommended battery of neuropsychological tests covering 7 areas. Neurocognitive impairment (NCI) was determined and also a global deficit score (GDS) for study comparisons.

RESULTS

Seventeen patients on LPV/r-MT and 17 on LPV/r-ART were included. Fourteen (82.4%) patients on LPV/r-MT and 16 (94.1%) on LPV/r-ART had HIV-1 RNA <1 copy/mL in CSF (p = 0.601). NCI was observed in 7 patients on LPV/r-MT and in 10 on LPV/r-ART (41% vs 59%; p = 0.494). Mean (SD) GDS was 0.22 (0.20) in patients on LPV/r-MT and 0.47 (0.34) in those on LPV/r-ART (p = 0.012).

CONCLUSIONS

Suppression of HIV in CSF is similar in individuals with durable plasma HIV-1 RNA suppression who are receiving LPV/r-MT or LPV/r-ART for at least 96 weeks. Findings for HIV-1 replication in CSF and neurocognitive status indicate that this strategy seems to be safe for CNS functioning.

Lopinavir plasma concentrations and virological outcome with lopinavir-ritonavir monotherapy in HIV-1-infected patients

There is significant intra- and intersubject variability in lopinavir (LPV) plasma concentrations after standard dosing; thus, this prospective study was conducted to determine whether low plasma LPV concentrations could be associated with virological outcome throughout lopinavir-ritonavir maintenance monotherapy (mtLPVr) in the clinical practice setting. If this hypothesis would be confirmed, LPV drug monitoring could improve the efficacy of mtLPVr regimens. Patients with previous virological failure (VF) on protease inhibitor-based regimens were also included if the genotypic resistance tests showed no major resistance mutation associated with reduced susceptibility to lopinavir-ritonavir. VF was defined as 2 consecutive determinations of HIV RNA levels of >200 copies/ml. Efficacy was analyzed by per-protocol analysis. Plasma LPV trough concentrations were measured by high-performance liquid chromatography using a UV detector. A total of 127 patients were included (22% with previous failure on protease inhibitors). After 96 weeks, the efficacy rate was 82.3% (95% confidence interval [CI(95)], 75.3 to 89.3%). Virological efficacy was independent of LPV plasma concentrations even when LPVr was given once daily. An adherence of <90% (HR, 4.4 [CI(95), 1.78 to 10.8; P = 0.001]) and the presence of blips in the preceding 12 months (HR, 3.06 [CI(95), 1.17 to 8.01; P = 0.022]) were the only variables independently associated with time to VF. These findings suggest that the LPV concentrations achieved with the standard doses of LPVr are sufficient to maintain virological control during monotherapy and that measurement of LPV concentrations is not useful for predicting virological outcome. Tight control of viral replication in the previous months and strict adherence throughout the mtLPVr regimen could improve the virological efficacy of this maintenance regimen.

[Consensus statement of the National AIDS Plan Secretariat, Spanish Society of Emergency Medicine and AIDS Study Group of the Spanish Society of Infectious Diseases and Clinical Microbiology on Emergency and Human Immunodeficiency Virus Infection]

OBJECTIVE

Supporting non-HIV specialist professionals in the treatment of patients with urgent diseases resulting from HIV infection.

METHODS

These recommendations have been agreed by an expert panel from the National AIDS Plan Secretariat, the Spanish Society of Emergency Medicine, and the AIDS Study Group. A review has been made of the safety and efficacy results of clinical trials and cohort studies published in biomedical journals (PubMed and Embase) or presented at conferences. The strength of each recommendation (A, B, C) and the level of supporting evidence (I, II, III) are based on a modification of the criteria of the Infectious Diseases Society of America.

RESULTS

The data to be collected from the emergency medical history in order to recognize the patient at risk of HIV infection were specified. It stressed the basic knowledge of ART principles and its importance in terms of decline in morbidity and mortality of HIV+ patients and referring to the HIV specialist for follow-up, where appropriate, including drug interactions. Management of different emergency situations that may occur in patients with HIV infection is also mentioned.

CONCLUSIONS

The non-HIV specialist professional, will find the necessary tools to approach HIV patients with an emergency disease.

[The Spanish AIDS Study Group and Spanish National AIDS Plan (GESIDA/Secretaría del Plan Nacional sobre el Sida) recommendations for the treatment of tuberculosis in HIV-infected individuals (Updated January 2013)]

This consensus document was prepared by an expert panel of the Grupo de Estudio de Sida (GESIDA [Spanish AIDS Study Group]) and the Plan Nacional sobre el Sida (PNS [Spanish National AIDS Plan]). The document updates current guidelines on the treatment of tuberculosis (TB) in HIV-infected individuals contained in the guidelines on the treatment of opportunistic infections published by GESIDA and PNS in 2008. The document aims to facilitate the management and treatment of HIV-infected patients with TB in Spain, and includes specific sections and recommendations on the treatment of drug-sensitive TB, multidrug-resistant TB, and extensively drug-resistant TB, in this population. The consensus guidelines also make recommendations on the treatment of HIV-infected patients with TB in special situations, such as chronic liver disease, pregnancy, kidney failure, and transplantation. Recommendations are made on the timing and initial regimens of antiretroviral therapy in patients with TB, and on immune reconstitution syndrome in HIV-infected patients with TB who are receiving antiretroviral therapy. The document does not cover the diagnosis of TB, diagnosis/treatment of latent TB, or treatment of TB in children. The quality of the evidence was evaluated and the recommendations graded using the approach of the Grading of Recommendations Assessment, Development and Evaluation Working Group.

Stavudine extended release (once-daily, Bristol-Myers Squibb) for the treatment of HIV/AIDS

INTRODUCTION

Stavudine extended release (d4T XR) was a formulation which tried to solve the two main problems associated with the use of stavudine immediate release (d4T IR). These were twice daily dosing schema at a time when most formulations were long-life allowing once daily dosing; and that the use of d4T IR was associated with long-term toxicity through mitochondrial toxicity clinically expressed as peripheral neuropathy, pancreatitis and above all, lipodystrophy. The link between stavudine exposure and lipodystrophy had a great negative impact on its use in clinical practice.

AREAS COVERED

The authors cover the most relevant papers related to the efficacy and safety of d4T XR-based antiretroviral therapy.

EXPERT OPINION

The development of d4T XR has only been partially successful with regard to its objectives. Improved pharmacokinetic properties allow its once daily dosing, and although it exhibits less mitochondrial toxicity it is still hampered by its development in a significant proportion of patients. This has caused its use to be almost residual in industrialised countries. As of now, d4T XR has not been made available in developing countries, despite the extended use of the immediate-release formulation. Currently, if there is no other chance of starting combination antiretroviral therapy, d4T XR could play a role in the treatment of HIV infection.

Boosted protease inhibitor monotherapy in HIV-infected adults: outputs from a pan-European expert panel meeting

While the introduction of combination highly active antiretroviral therapy (HAART) regimens represents an important advance in the management of human immunodeficiency virus (HIV)-infected patients, tolerability can be an issue and the use of several different agents may produce problems. The switch of combination HAART to ritonavir-boosted protease inhibitor (PI) monotherapy may offer the opportunity to maintain antiviral efficacy while reducing treatment complexity and the risks of toxicity. Current European AIDS Clinical Society (EACS) guidelines recognise ritonavir-boosted PI monotherapy with twice-daily lopinavir/ritonavir or once-daily darunavir/ritonavir as a possible option in patients who have intolerance to nucleoside reverse transcriptase inhibitors, or for treatment simplification. Clinical trials data for PI boosted monotherapy are encouraging, showing substantial efficacy in the majority of patients; however, further data are required before this approach can be recommended as a routine treatment. Available data indicate that the most suitable candidates for the use of boosted PI monotherapy are long-term virologically suppressed patients who have demonstrated good adherence to antiretroviral therapy, who do not have chronic hepatitis B, have no history of treatment failure on PIs and are able to tolerate low-dose ritonavir.

[Costs and cost-efficacy analysis of the preferred treatments by GESIDA/National Plan for AIDS for the initial antiretroviral therapy in adult human immunodeficiency virus (HIV) infected patients in 2012]

INTRODUCTION

The GESIDA and National AIDS Plan panel of experts propose «preferred regimens» of antiretroviral treatment (ART) as initial therapy in HIV infected patients for 2012. The objective of this study is to evaluate the costs and the efficiency of initiating treatment with these «preferred regimens».

METHODS

Economic assessment of costs and efficiency (cost/efficacy) using decision tree analysis model. Efficacy was defined as the probability of having a viral load <50 copies/ml at week 48, in an intention-to-treat analysis. Cost of initiating treatment with an ART regime was defined as the costs of ART and all its consequences (adverse effects, changes of ART regime, and drug resistance analyses) during the first 48 weeks. The perspective of the analysis is that of the National Health System, considering only differential direct costs: ART (official prices), management of adverse effects, studies of resistance and determination of HLA B 5701. The setting is Spain and the costs are those of 2012. A sensitivity deterministic analysis was conducted, building three scenarios for each regime: baseline, most favourable, and most unfavourable cases.

RESULTS

In the baseline case scenario, the cost of initiating treatment ranges from 6,895 euros for TDF/FTC+NVP to 12,067 euros for TDF/FTC+RAL. The efficacy ranges between 0.66 for ABC/3TC+LPV/r and 0.87 for TDF/FTC+RAL. Efficiency, in terms of cost/efficacy, varies between 9,387 and 13,823 euros per responder at 48 weeks, for TDF/FTC/EFV and TDF/FTC+RAL, respectively. In the most unfavourable scenario, the most efficient regime is TDF/FTC+NVP (9,742 per responder).

CONCLUSION

Considering the official prices of ART, the most efficient regimens are TDF/FTC/EFV (baseline case and most favourable scenarios), and TDF/FTC+NVP (most unfavourable scenario).

Differences in resistance mutations among HIV-1 non-subtype B infections: a systematic review of evidence (1996-2008)

Ninety percent of HIV-1-infected people worldwide harbour non-subtype B variants of HIV-1. Yet knowledge of resistance mutations in non-B HIV-1 and their clinical relevance is limited. Although a few reviews, editorials and perspectives have been published alluding to this lack of data among non-B subtypes, no systematic review has been performed to date.With this in mind, we conducted a systematic review (1996-2008) of all published studies performed on the basis of non-subtype B HIV-1 infections treated with antiretroviral drugs that reported genotype resistance tests. Using an established search string, 50 studies were deemed relevant for this review.These studies reported genotyping data from non-B HIV-1 infections that had been treated with either reverse transcriptase inhibitors or protease inhibitors. While most major resistance mutations in subtype B were also found in non-B subtypes, a few novel mutations in non-B subtypes were recognized. The main differences are reflected in the discoveries that: (i) the non-nucleoside reverse transcriptase inhibitor resistance mutation, V106M, has been seen in subtype C and CRF01_AE, but not in subtype B, (ii) the protease inhibitor mutations L89I/V have been reported in C, F and G subtypes, but not in B, (iii) a nelfinavir selected non-D30N containing pathway predominated in CRF01_AE and CRF02_AG, while the emergence of D30N is favoured in subtypes B and D, (iv) studies on thymidine analog-treated subtype C infections from South Africa, Botswana and Malawi have reported a higher frequency of the K65R resistance mutation than that typically seen with subtype B.Additionally, some substitutions that seem to impact non-B viruses differentially are: reverse transcriptase mutations G196E, A98G/S, and V75M; and protease mutations M89I/V and I93L.Polymorphisms that were common in non-B subtypes and that may contribute to resistance tended to persist or become more frequent after drug exposure. Some, but not all, are recognized as minor resistance mutations in B subtypes. These observed differences in resistance pathways may impact cross-resistance and the selection of second-line regimens with protease inhibitors. Attention to newer drug combinations, as well as baseline genotyping of non-B isolates, in well-designed longitudinal studies with long duration of follow up are needed.