Safety and efficacy of raltegravir-based versus efavirenz-based combination therapy in treatment-naive patients with HIV-1 infection: a multicentre, double-blind randomised controlled trial

Population pharmacokinetic analysis of raltegravir pediatric formulations in HIV-infected children 4 weeks to 18 years of age

P1066 is an open-label study of raltegravir in HIV positive youth, ages 4 weeks-18 years. Here we summarize P1066 pharmacokinetic (PK) data and a population PK model for the pediatric chewable tablet and oral granules. Raltegravir PK parameters were calculated using noncompartmental analysis. A 2-compartment model was developed using data from P1066 and an adult study of the pediatric formulations. Interindividual variability was described by an exponential error model, and residual variability was captured by an additive/proportional error model. Twelve-hour concentrations (C12h ) were calculated from the model-derived elimination rate constant and 8-hour observed concentration. Simulated steady-state concentrations were analyzed by noncompartmental analysis. Target area under the curve (AUC0-12h ) and C12h were achieved in each cohort. For the pediatric formulations, geometric mean AUC0-12h values were 18.0-22.6 μM-hr across cohorts, and C12h values were 71-130 nM, with lower coefficients of variation versus the film-coated tablet. A 2-compartment model with first-order absorption adequately described raltegravir plasma PK in pediatric and adult patients. Weight was a covariate on clearance and central volume and was incorporated using allometric scaling. Raltegravir chewable tablets and oral granules exhibited PK parameters consistent with those from prior adult studies and older children in P1066, as well as lower variability than the film-coated tablet.

Efficacy and safety of efavirenz 400 mg daily versus 600 mg daily: 96-week data from the randomised, double-blind, placebo-controlled, non-inferiority ENCORE1 study

BACKGROUND

The week 48 primary analysis of the ENCORE1 trial established the virological non-inferiority and safety of efavirenz 400 mg compared with the standard 600 mg dose, combined with tenofovir and emtricitabine, as first-line HIV therapy. This 96-week follow-up of the trial assesses the durability of efficacy and safety of this treatment over 96 weeks.

METHODS

ENCORE1 was a double-blind, placebo-controlled, non-inferiority trial done at 38 clinical sites in 13 countries. HIV-infected adult patients (≥16 years of age) with no previous antiretroviral therapy, a CD4 cell count of 50-500 cells per μL, and plasma HIV-1 viral load of at least 1000 copies per mL were randomly assigned (1:1) by an electronic case report form to receive fixed-dose daily tenofovir 300 mg and emtricitabine 200 mg plus efavirenz either 400 mg daily or 600 mg daily. Participants, physicians, and all other trial staff were masked to treatment assignment. Randomisation was stratified by HIV-1 viral load at baseline (≤ or >100 000 copies per mL). The primary endpoint was the difference in the proportions of patients in the two treatment groups with a plasma HIV-1 viral load below 200 copies per mL at week 96. Treatment groups were deemed to be non-inferior if the lower limit of the 95% CI for the difference in viral load was above -10% by modified intention-to-treat analysis. Non-inferiority was assessed in the modified intention-to-treat, per-protocol, and non-completer=failure (NC=F) populations. Adverse events and serious adverse events were summarised by treatment group. This study is registered with ClinicalTrials.gov, number NCT01011413.

FINDINGS

Between Aug 24, 2011, and March 19, 2012, 636 eligible participants were enrolled and randomly assigned to the two treatment groups (324 to efavirenz 400 mg and 312 to efavirenz 600 mg). The intention-to-treat population who received at least one dose of study drug comprised 630 patients: 321 in the efavirenz 400 mg group and 309 in the efavirenz 600 mg group. 585 patients (93%; 299 in the efavirenz 400 mg group and 286 in the 600 mg group) completed 96 weeks of follow-up. At 96 weeks, 289 (90·0%) of 321 patients in the efavirenz 400 mg group and 280 (90·6%) of 309 in the efavirenz 600 mg group had a plasma HIV-1 viral load less than 200 copies per mL (difference -0·6, 95% CI -5·2 to 4·0; p=0·72), which suggests continued non-inferiority of the lower efavirenz dose. Non-inferiority was recorded for thresholds of less than 50 and less than 400 copies per mL, irrespective of baseline plasma viral load. Adverse events were reported by 291 (91%) of 321 patients in the efavirenz 400 mg group and by 285 (92%) of 309 in the 600 mg group (p=0·48). The proportions of patients reporting an adverse event that was definitely or probably related to efavirenz were 126 (39%) for efavirenz 400 mg and 148 (48%) for efavirenz 600 mg (p=0·03). The number of patients who reported serious adverse events did not differ between the groups (p=0·20).

INTERPRETATION

Our findings confirm that efavirenz 400 mg is non-inferior to the standard dose of 600 mg in combination with tenofovir and emtricitabine as initial HIV therapy over 96 weeks. Fewer efavirenz-related adverse events were reported with the 400 mg efavirenz dose than with the 600 mg dose. These findings support the routine use of efavirenz 400 mg. The coadministration of rifampicin and efavirenz 400 mg needs further investigation.

FUNDING

Bill & Melinda Gates Foundation, and UNSW Australia.

Efficacy of tenofovir and efavirenz in combination with lamivudine or emtricitabine in antiretroviral-naive patients in Europe

BACKGROUND

The combination of tenofovir and efavirenz with either lamivudine or emtricitabine (TELE) has proved to be highly effective in clinical trials for first-line treatment of HIV-1 infection. However, limited data are available on its efficacy in routine clinical practice.

METHODS

A multicentre cohort study was performed in therapy-naive patients initiating ART with TELE before July 2009. Efficacy was studied using ITT (missing or switch = failure) and on-treatment (OT) analyses. Genotypic susceptibility scores (GSSs) were determined using the Stanford HIVdb algorithm.

RESULTS

Efficacy analysis of 1608 patients showed virological suppression to <50 copies/mL at 48 weeks in 91.5% (OT) and 70.6% (ITT). Almost a quarter of all patients (22.9%) had discontinued TELE at week 48, mainly due to CNS toxicity. Virological failure within 48 weeks was rarely observed (3.3%, n = 53). In multilevel, multivariate analysis, infection with subtype B (P = 0.011), baseline CD4 count <200 cells/mm³ (P < 0.001), GSS <3 (P = 0.002) and use of lamivudine (P < 0.001) were associated with a higher risk of virological failure. After exclusion of patients using co-formulated compounds, virological failure was still more often observed with lamivudine. Following virological failure, three-quarters of patients switched to a PI-based regimen with GSS <3. After 1 year of second-line therapy, viral load was suppressed to <50 copies/mL in 73.5% (OT).

CONCLUSIONS

In clinical practice, treatment failure on TELE regimens is relatively frequent due to toxicity. Virological failure is rare and more often observed with lamivudine than with emtricitabine. Following virological failure on TELE, PI-based second-line therapy was often successful despite GSS <3.

Collateral Resistance and Sensitivity Modulate Evolution of High-Level Resistance to Drug Combination Treatment in Staphylococcus aureus

As drug-resistant pathogens continue to emerge, combination therapy will increasingly be relied upon to treat infections and to help combat further development of multidrug resistance. At present a dichotomy exists between clinical practice, which favors therapeutically synergistic combinations, and the scientific model emerging from in vitro experimental work, which maintains that this interaction provides greater selective pressure toward resistance development than other interaction types. We sought to extend the current paradigm, based on work below or near minimum inhibitory concentration levels, to reflect drug concentrations more likely to be encountered during treatment. We performed a series of adaptive evolution experiments using Staphylococcus aureus. Interestingly, no relationship between drug interaction type and resistance evolution was found as resistance increased significantly beyond wild-type levels. All drug combinations, irrespective of interaction types, effectively limited resistance evolution compared with monotreatment. Cross-resistance and collateral sensitivity were found to be important factors in the extent of resistance evolution toward a combination. Comparative genomic analyses revealed that resistance to drug combinations was mediated largely by mutations in the same genes as single-drug-evolved lineages highlighting the importance of the component drugs in determining the rate of resistance evolution. Results of this work suggest that the mechanisms of resistance to constituent drugs should be the focus of future resistance evolution work.

Protease Inhibitors and Renal Function in Patients with HIV Infection: a Systematic Review

INTRODUCTION

Despite antiretroviral (ARV) therapy reducing renal disease in human immunodeficiency virus overall, there is concern that certain ARVs, particularly tenofovir disoproxil fumarate (TDF) with or without a boosted protease inhibitor (PI), may reduce renal function over time. It is not known whether effects seen with PI-based regimens are independent, result from interactions with TDF coadministration, or are artefactual owing to inhibition of renal tubular creatinine transport by ritonavir or cobicistat pharmacoenhancement. The aim of this review was to conduct a systematic review of studies, weighted toward high-quality evidence, examining changes in renal function over time with PI-based regimens.

METHODS

PubMed, Embase, and Medline databases and conference abstracts were searched using pre-defined terms for English language articles, published up to and including August 12, 2013, describing changes in renal function over time with PI-based regimens. All available randomized controlled trials (RCTs) were selected; however, to reduce bias, only observational studies recruiting from more than one center and analyzing data from more than 1,000 patients were included. Evidence was qualitatively evaluated according to levels established by the Oxford Centre for Evidence-Based Medicine (OCEBM).

RESULTS

A total of 2,322 articles were retrieved by the initial search. Of these, 37 were selected for full review, comprising 24 RCTs (OCEBM Level 1 evidence: 4 reports of fully double-blinded or blinded with respect to the PI component). The remaining 20 RCTs and 13 observational studies qualified as OCEBM Level 2 evidence. Level 1 evidence showed initial but non-progressive increases in serum creatinine and corresponding decreases in estimated glomerular filtration rate (eGFR), suggesting an effect on renal tubular transport of creatinine. Level 2 evidence suggested that atazanavir and lopinavir especially in combination with TDF were associated with non-progressive reductions in eGFR over time, with a decreased risk for the development of chronic kidney disease (CKD) on cessation and without the development of advanced CKD or end-stage renal disease (ESRD); whether these reductions were independent or associated with interactions with coadministered TDF could not be established with certainty. Data on darunavir were insufficient to draw any conclusions. The principal limitation of the reviewed studies was the lack of standardization of creatinine measurements in virtually all studies and the lack of corroborative data on changes in proteinuria or other indices of renal function.

DISCUSSION

In this review, there was little evidence for progressive changes in eGFR, or the development of advanced CKD, or ESRD with lopinavir or atazanavir. Further long-term studies, employing a wide range of validated renal function assessments, are required to fully evaluate potential association of PIs with CKD.

Combination dolutegravir-abacavir-lamivudine in the management of HIV/AIDS: clinical utility and patient considerations

The current standard of care for human immunodeficiency virus (HIV) treatment is a three-drug regimen containing a nonnucleoside reverse transcriptase inhibitor, a protease inhibitor, or an integrase strand transfer inhibitor (INSTI) plus two nucleoside/tide reverse transcriptase inhibitors. Given their potency, safety, and distinctive mechanism of action, INSTIs represent an important advance in HIV type 1 (HIV-1) therapy. Dolutegravir (DTG) is a new-generation INSTI recently approved for the treatment of HIV-1-infected adult patients, with distinct advantages compared with other available antiretroviral agents. In well-designed, large clinical trials, DTG-containing regimens have demonstrated either noninferiority or superiority to current first-line agents such as raltegravir-, darunavir/ritonavir-, and efavirenz-containing regimens. The favorable safety profile, low potential for drug interactions, minimal impact on lipids, good tolerability, and high resistance barrier of DTG makes this compound one of the preferred choices for HIV therapy in multiple clinical scenarios, including treatment-naïve and treatment-experienced patients. DTG is the only antiretroviral drug not yet associated with de novo emergence of resistance mutations in treatment-naïve individuals. However, data from in vitro studies and clinical trial suggest the possibility of cross-resistance between first- and second-generation INSTIs. Even though these profiles are infrequent at the moment, they need to be monitored in all current patients treated with INSTIs. With its potent activity, good tolerability, simplicity of dosing, and minimal drug interaction profile, DTG will likely play a major role in the management of patients with HIV-1 infection. On the basis of clinical trial data, current guidelines endorse DTG in combination with nucleoside/tide reverse transcriptase inhibitors as one of the recommended regimens in antiretroviral therapy-naïve patients. Most of the favorable clinical experiences from clinical trials are based on the combination of DTG with abacavir/lamivudine, and DTG is planned to be coformulated with abacavir/lamivudine. This will provide a further advantage, given that single tablet regimens are associated with higher adherence rates as well as improvement in quality of life and enhanced patient preference.

Skeletal muscle toxicity in HIV-1-infected patients treated with a raltegravir-containing antiretroviral therapy: a cohort study

To evaluate the frequency of myopathy and serum creatine kinase (CK) elevation associated with the use of the integrase inhibitor raltegravir we conducted a retrospective, cohort analysis assessing the incidence of skeletal muscle toxicity among HIV-infected patients treated with raltegravir. Adult HIV-infected patients who started a raltegravir-containing therapy were enrolled into the study. The skeletal muscle toxicity was defined by the presence of one or more of the following parameters: (1) isolated and significant CK elevation without signs or symptoms; (2) diffuse myalgia without weakness; (3) proximal muscle weakness; (4) rhabdomyolysis. On the whole, 155 patients were included in the study, with a mean age of 49.2 years; the median duration of the raltegravir treatment was 30.7 months. The overall frequency of skeletal muscle toxicity was 23.9%, with an incidence of 4.7/100 person-years. An isolated CK elevation was reported in 21.3% of cases, while less than 3% of patients complained of myalgia or muscle weakness. The CK elevation was usually of grade 1 or 2 and self-limiting, and laboratory or clinical abnormalities did not require discontinuation of raltegravir in any patient. Factors significantly associated with skeletal muscle toxicity were previous use of zidovudine, higher baseline CK levels, previous increase of the CK levels, and a higher body mass index. Skeletal muscle toxicity is not an unusual adverse event in subjects receiving raltegravir, but it is usually represented by a mild-to-moderate increase in CK concentration, while clinical symptoms of myopathy are very uncommon.

Ritonavir-boosted darunavir combined with raltegravir or tenofovir-emtricitabine in antiretroviral-naive adults infected with HIV-1: 96 week results from the NEAT001/ANRS143 randomised non-inferiority trial

BACKGROUND

Standard first-line antiretroviral therapy for HIV-1 infection includes two nucleoside or nucleotide reverse transcriptase inhibitors (NtRTIs), but these drugs have limitations. We assessed the 96 week efficacy and safety of an NtRTI-sparing regimen.

METHODS

Between August, 2010, and September, 2011, we enrolled treatment-naive adults into this randomised, open-label, non-inferiority trial in treatment-naive adults in 15 European countries. The composite primary outcome was change to randomised treatment before week 32 because of insufficient virological response, no virological response by week 32, HIV-1 RNA concentration 50 copies per mL or higher at any time after week 32; death from any cause; any new or recurrent AIDS event; or any serious non-AIDS event. Patients were randomised in a 1:1 ratio to receive oral treatment with 400 mg raltegravir twice daily plus 800 mg darunavir and 100 mg ritonavir once daily (NtRTI-sparing regimen) or tenofovir-emtricitabine in a 245 mg and 200 mg fixed-dose combination once daily, plus 800 mg darunavir and 100 mg ritonavir once daily (standard regimen). This trial was registered with ClinicalTrials.gov, number NCT01066962.

FINDINGS

Of 805 patients enrolled, 401 received the NtRTI-sparing regimen and 404 the standard regimen, with median follow-up of 123 weeks (IQR 112-133). Treatment failure was seen in 77 (19%) in the NtRTI-sparing group and 61 (15%) in the standard group. Kaplan-Meier estimated proportions of treatment failure by week 96 were 17·8% and 13·8%, respectively (difference 4·0%, 95% CI -0·8 to 8·8). The frequency of serious or treatment-modifying adverse events were similar (10·2 vs 8·3 per 100 person-years and 3·9 vs 4·2 per 100 person-years, respectively).

INTERPRETATION

Our NtRTI-sparing regimen was non-inferior to standard treatment and represents a treatment option for patients with CD4 cell counts higher than 200 cells per μL.

FUNDING

European Union Sixth Framework Programme, Inserm-ANRS, Gilead Sciences, Janssen Pharmaceuticals, Merck Laboratories.

Lipemia retinalis as a presenting feature of hypertriglyceridemia associated with protease inhibitors in human immunodeficiency virus-infected patients

PURPOSE

To report two cases of lipemia retinalis in patients infected with human immunodeficiency virus on protease inhibitors with increased triglyceride levels.

METHODS

Retrospective review of medical records. Two patients infected with human immunodeficiency virus using protease inhibitors who were diagnosed with severe hypertriglyceridemia based on eye findings of lipemia retinalis.

RESULTS

One patient developed triglyceride level of >5,300 mg/dL after adding an integrase inhibitor to a regimen that included protease inhibitors. Hypertriglyceridemia was diagnosed after routine ophthalmic screening for cytomegalovirus retinitis revealed lipemia retinalis. Triglyceride levels improved significantly after both discontinuation of HIV medications and adjustment of cholesterol-lowering medications. Another patient developed triglyceride levels of >9,000 mg/dL while on protease inhibitors, which was also detected on routine retinal examination. Shortly after the diagnosis, he experienced acute coronary syndrome and cardiac arrest requiring plasmapheresis and emergent bypass surgery.

CONCLUSION

Lipemia retinalis is rare but may be a presenting sign of severe hypertriglyceridemia in patients infected with human immunodeficiency virus. Recognition of this condition during the ophthalmic examination can lead to diagnosis and may allow for treatment before the development of life-threatening complications, such as pancreatitis and acute coronary syndrome.

Muscle symptoms and creatine phosphokinase elevations in patients receiving raltegravir in clinical practice: Results from the SCOLTA project long-term surveillance

Muscle alterations ranging from asymptomatic creatine phosphokinase (CPK) increases to rhabdomyolysis and central nervous system (CNS) symptoms have been reported in patients receiving raltegravir. Muscle symptoms and CPK increases were investigated in a cohort of HIV-infected patients receiving raltegravir-based antiretroviral therapy, and possible associated predictors were evaluated. The SCOLTA Project is a prospective, observational, multicentre study created to assess the incidence of adverse events in patients receiving new antiretroviral drugs in clinical practice. In total, 496 HIV-infected patients were enrolled [333 (67.1%) male]. CDC stage was C in 196 patients (39.5%). Mean age at enrolment was 45.9 ± 9.3 years. Median follow-up was 21 months. Twenty-six patients (5.2%) reported muscle symptoms (16 muscle pain and 17 weakness; 7 had both). Of 342 patients with normal baseline CPK values, 72 (21.1%) had a CPK increase. Seven patients (1.4%) discontinued raltegravir because of muscular events (three for muscle pain/weakness and four CPK increases). No cases of rhabdomyolysis were observed. Patients with muscle symptoms were more frequently receiving in their regimen than those not receiving atazanavir (P=0.04) and were more likely to also report CNS symptoms (P<0.0001). Significant predictors of muscle symptoms were CNS symptoms and use of atazanavir. Female sex was associated with a reduced risk of CPK increase. In conclusion, muscle symptoms and CPK elevations occurred frequently and caused most discontinuations due to adverse events. Their monitoring in patients receiving raltegravir should be considered, especially when co-administered with atazanavir or when CNS symptoms are also present.

Use of efavirenz or atazanavir/ritonavir is associated with better clinical outcomes of HAART compared to other protease inhibitors: routine evidence from the Italian MASTER Cohort

Randomized trials and observational cohorts reported higher rates of virological suppression after highly active antiretroviral therapy (HAART) including efavirenz (EFV), compared with boosted protease inhibitors (PIs). Correlations with immunological and clinical outcomes are unclear. Patients of the Italian MASTER cohort who started HAART from 2000 to 2010 were selected. Outstanding outcome (composite outcome for success (COS)) was introduced. We evaluated predictors of COS (no AIDS plus CD4+ count >500/mm(3)plus HIV-RNA <500 copies/mL) and of eight single outcomes either at month 6 or at year 3. Multivariable logistic regression was conducted. There were 6259 patients selected. Patients on EFV (43%) were younger, had greater CD4+ count, presented with AIDS less frequently, and more were Italians. At year 3, 90% of patients had HIV RNA <500 copies/mL, but only 41.4% were prescribed EFV, vs. 34.1% prescribed boosted PIs achieved COS (p <0.0001). At multivariable analysis, patients on lopinavir/ritonavir had an odds ratio of 0.70 for COS at year 3 (p <0.0001). Foreign origin and positive hepatitis C virus-Ab were independently associated with worse outcome (OR 0.54, p <0.0001 and OR 0.70, p 0.01, respectively). Patients on boosted PIs developed AIDS more frequently either at month 6 (13.8% vs. 7.6%, p <0.0001) or at year 3 (17.1% vs. 13.8%, p <0.0001). At year 3, deaths of patients starting EFV were 3%, vs. 5% on boosted PIs (p 0.008). In this study, naïve patients on EFV performed better than those on boosted PIs after adjustment for imbalances at baseline. Even when virological control is achieved, COS is relatively rare. Hepatitis C virus-positive patients and those of foreign origin are at risk of not obtaining COS.

Dolutegravir: a new HIV integrase inhibitor for the treatment of HIV infection

ABSTRACT 

Dolutegravir is a second-generation HIV integrase strand transfer inhibitor (INSTI) and the most recent antiretroviral approved for treatment of HIV-1 infection. Dolutegravir in combination with two nucleoside reverse transcriptase inhibitors is one of the preferred regimens recommended by the Department of Health and Human Services HIV treatment guidelines for treatment-naive adults and adolescents. This recommendation is based on clinical trial data where dolutegravir demonstrated superiority compared with guideline preferred regimens containing efavirenz and ritonavir-boosted darunavir and noninferiority compared with first-generation INSTI, raltegravir. Dolutegravir also demonstrated superiority when compared with raltegravir in treatment-experienced, integrase-naive patients and clinical efficacy in patients with resistance to first-generation INSTIs. Overall, dolutegravir has demonstrated excellent tolerability, limited drug interactions, minimal drug resistance and once-daily dosing for treatment-naive patients.

Significant reduction in HIV virologic failure during a 15-year period in a setting with free healthcare access

BACKGROUND

Calendar trends in virologic failure (VF) among human immunodeficiency virus (HIV)-infected patients can help to evaluate the performance of healthcare systems and the need for new antiretroviral therapy (ART). We examined the time trend in the rate of VF beyond 6 months of ART between 1997 and 2011 in France.

METHODS

We included patients from the French Hospital Database on HIV who received at least 6 months of ART. VF was defined as 2 consecutive plasma HIV-RNA values >500 copies/mL or as 1 value >500 copies/mL followed by a treatment switch. We adjusted for patients' characteristics by fitting a multivariable generalized estimating equation logistic regression model with an exchangeable covariance matrix.

RESULTS

A total of 81 738 patients were enrolled, and median follow-up was 112.4 months. Median CD4 count was 333 cells/µL, and 23% of patients had HIV infection classified as Centers for Disease Control and Prevention stage C. Overall, 29.3% of patients received single/dual-drug ART initially, and 45.4% of patients experienced at least 1 episode of VF during follow-up. The percentage of patients with VF fell from 61.5% in 1997-1998 to 9.7% in 2009-2011 (P < .0001). Factors associated with the lower frequency of VF were recent calendar period, a higher contemporary CD4 cell count, and first-line regimens based on nonnucleoside reverse transcriptase inhibitors or integrase inhibitors.

CONCLUSIONS

The proportion of HIV-infected patients experiencing VF during routine care fell markedly between 1997 and 2009-2011, to only 9.7%. This was attributed to the advent of fully active and better-tolerated antiretroviral drugs, and to national guidelines recommending rapid management of VF after mid-2000.

Impact of the HIV integrase genetic context on the phenotypic expression and in vivo emergence of raltegravir resistance mutations

OBJECTIVES

HIV resistance to the integrase inhibitor raltegravir in treated patients is characterized by distinct resistance pathways. We hypothesize that differences in the in vivo dynamics of HIV resistance to raltegravir are due to the genetic context of the integrase present at baseline.

PATIENTS AND METHODS

We studied four patients whose viruses evolved towards different resistance pathways. The integrase baseline sequences were inserted into a reference clone. Primary resistance mutations were then introduced and their impact on viral replication capacity (RC) and resistance was measured.

RESULTS

Patients A and B experienced emergence and persistence of mutation N155H under raltegravir therapy. In the integrase sequence from Patient A, N155H conferred potent resistance coupled with a lower impact on RC than Q148H. In Patient B, instead, selection of N155H could be explained by the dramatic loss of RC induced by the alternative Q148H mutation. In Patient C, N155H initially emerged and was later replaced by Q148H. In this integrase context, N155H resulted in higher RC but lower resistance than Q148H. In Patient D, Q148H rapidly emerged without appearance of N155H. This was the only patient for whom Q148H conferred higher RC and resistance than N155H.

CONCLUSIONS

The emergence of different resistance mutations in patients was in full agreement with the impact of mutations in different baseline integrase contexts. Evolution towards different resistance genotypes is thus largely determined by the capacity of different integrase sequences present at baseline to minimize the effect of mutations on virus RC while allowing expression of resistance.

Week 144 resistance analysis of elvitegravir/cobicistat/emtricitabine/tenofovir DF versus efavirenz/emtricitabine/tenofovir DF in antiretroviral-naive patients

BACKGROUND

Here, the baseline and emergent resistance to elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF) versus efavirenz (EFV)/FTC/TDF in HIV-1-infected antiretroviral-naive adults through 144 weeks from the randomized, ongoing, Phase III study GS-US-236-0102 is described.

METHODS

HIV-1 protease (PR) and reverse transcriptase (RT) were sequenced at screening; patients with HIV-1 resistant to EFV, FTC or TDF were excluded. Genotypic/phenotypic analyses were performed at virological failure confirmation and baseline for PR, RT and integrase (IN) for patients with virological failure and for patients with HIV-1 RNA≥400 copies/ml at weeks 48, 96, 144 or early study drug discontinuation. Retrospective, baseline, IN genotyping was conducted for EVG/COBI/FTC/TDF patients.

RESULTS

In the EVG/COBI/FTC/TDF group through week 144, HIV-1 from 10 patients (2.9%; 10/348 treated patients) developed primary IN strand transfer inhibitor (n=9) and/or nucleoside RT inhibitor resistance substitutions (n=10). The emergence of resistance decreased over time with 8, 2 and 0 patients developing HIV-1 resistance through week 48, post-week 48-96 and post-week 96-144, respectively. Emergent substitutions were E92Q (n=7), N155H (n=3), Q148R (n=1) and T66I (n=1) in IN, and M184V/I (n=10) and K65R (n=4) in RT. All 10 isolates had reduced susceptibility to EVG, FTC or TDF. Virus with EVG phenotypic resistance had cross-resistance to raltegravir. In the EFV/FTC/TDF group, virus from 14 patients (4.0%; 14/352 treated patients; 4 during weeks 96-144) developed a resistance substitution to EFV (n=14; K103N: n=13), FTC (M184V/I: n=4) or TDF (K65R: n=3).

CONCLUSIONS

Resistance development to EVG/COBI/FTC/TDF was infrequent through 144 weeks of therapy and decreased over time, consistent with durable efficacy.

48-week efficacy and safety of dolutegravir relative to commonly used third agents in treatment-naive HIV-1-infected patients: a systematic review and network meta-analysis

BACKGROUND

A network meta-analysis can provide estimates of relative efficacy for treatments not directly studied in head-to-head randomized controlled trials. We estimated the relative efficacy and safety of dolutegravir (DTG) versus third agents currently recommended by guidelines, including ritonavir-boosted atazanavir (ATV/r), ritonavir-boosted darunavir (DRV/r), efavirenz (EFV), cobicistat-boosted elvitegravir (EVG/c), ritonavir-boosted lopinavir (LPV/r), raltegravir (RAL), and rilpivirine (RPV), in treatment-naive HIV-1-infected patients.

METHODS

A systematic review of published literature was conducted to identify phase 3/4 randomized controlled clinical trials (up to August 2013) including at least one third agent of interest in combination with a backbone nucleoside reverse transcriptase inhibitor (NRTI) regimen. Bayesian fixed-effect network meta-analysis models adjusting for the type of nucleoside reverse transcriptase inhibitor backbone (tenofovir disoproxil fumarate/emtricitabine [TDF/FTC] or abacavir/lamivudine [ABC/3TC]) were used to evaluate week 48 efficacy (HIV-RNA suppression to <50 copies/mL and change in CD4+ cells/µL) and safety (lipid changes, adverse events, and discontinuations due to adverse events) of DTG relative to all other treatments. Sensitivity analyses assessing the impact of NRTI treatment adjustment and random-effects models were performed.

RESULTS

Thirty-one studies including 17,000 patients were combined in the analysis. Adjusting for the effect of NRTI backbone, treatment with DTG resulted in significantly higher odds of virologic suppression (HIV RNA<50 copies/mL) and increase in CD4+ cells/µL versus ATV/r, DRV/r, EFV, LPV/r, and RPV. Dolutegravir had better or equivalent changes in total cholesterol, LDL, triglycerides, and lower odds of adverse events and discontinuation due to adverse events compared to all treatments. Random-effects and unadjusted models resulted in similar conclusions.

CONCLUSION

Three clinical trials of DTG have demonstrated comparable or superior efficacy and safety to DRV, RAL, and EFV in HIV-1-infected treatment-naive patients. This network meta-analysis suggests DTG is also favorable or comparable to other commonly used third agents (ATV/r, LPV/r, RPV, and EVG/c).

The RADAR study: week 48 safety and efficacy of RAltegravir combined with boosted DARunavir compared to tenofovir/emtricitabine combined with boosted darunavir in antiretroviral-naive patients. Impact on bone health

Background

NRTI-sparing regimens may avoid long-term mitochondrial, bone and renal toxicities and maintain viral suppression.

Methods

In the RADAR study, 85 antiretroviral-naïve HIV-infected patients were randomized to receive either raltegravir (RAL) (n = 42) or tenofovir/emtricitabine (TDF/FTC) (n = 43), each with ritonavir-boosted darunavir (DRV/r). Virologic efficacy was assessed at weeks 24 and 48. Bone mineral density (BMD) was assessed by dual energy X-ray absorptiometry (DXA) scan at baseline and week 48, and bone turnover markers (BTM) assessed at weeks 0, 16 and 48.

Results

Using an intention-to-treat analysis, 62.5% of RAL subjects and 83.7% of TDF/FTC subjects were responders (VL<48 copies/mL) at week 48 (p = 0.045; chi-square test). The proportions of patients achieving VL<200 copies/mL were similar: 72.5% and 86.0% (p = 0.175). Premature treatment discontinuation was the main cause for failure. No treatment-emergent resistance was observed. Changes from baseline in RAL vs. TDF/FTC for CD4⁺ (+199 vs. +216 cells/µL, p = 0.63), total cholesterol/HDL (−0.25 vs. −0.71 mg/dL (p = 0.270), and eGFR (−4.4 vs. −7.9 ml/min, p = 0.44) were comparable between groups. Changes in subtotal BMD to week 48 were: +9.2 with RAL vs. −7 g/cm² with TDF/FTC (p = 0.002). Mean CTX changes were +0.04 vs. +0.24 ng/mL (p = 0.001), and mean P1NP changes were +3.59 vs. +30.09 ng/mL (p = 0.023). BTM changes at week 16 predicted change in BMD by week 48 (R = −0.394, p = 0.003 for CTX; and R = −0.477, p<0.001 for P1NP).

Conclusion

The NRTI-sparing regimen RAL+DRV/r did not achieve similar week 48 virologic efficacy compared with TDF/FTC+DRV/r, but was better with regard to markers of bone health.

Trial Registration

ClinicalTrials.gov NCT 00677300

Costs and cost-efficacy analysis of the 2014 GESIDA/Spanish National AIDS Plan recommended guidelines for initial antiretroviral therapy in HIV-infected adults

INTRODUCTION

GESIDA and the National AIDS Plan panel of experts suggest preferred (PR) and alternative (AR) regimens of antiretroviral treatment (ART) as initial therapy in HIV-infected patients for 2014. The objective of this study is to evaluate the costs and the efficiency of initiating treatment with these regimens.

METHODS

An economic assessment was made of costs and efficiency (cost/efficacy) based on decision tree analyses. Efficacy was defined as the probability of reporting a viral load <50 copies/mL at week 48, in an intention-to-treat analysis. Cost of initiating treatment with an ART regimen was defined as the costs of ART and its consequences (adverse effects, changes of ART regimen, and drug resistance studies) during the first 48 weeks. The payer perspective (National Health System) was applied by considering only differential direct costs: ART (official prices), management of adverse effects, studies of resistance, and HLA B*5701 testing. The setting is Spain and costs correspond to those of 2014. A sensitivity deterministic analysis was conducted, building three scenarios for each regimen: base case, most favourable and least favourable.

RESULTS

In the base case scenario, the cost of initiating treatment ranges from 5133 Euros for ABC/3TC+EFV to 11,949 Euros for TDF/FTC+RAL. The efficacy varies between 0.66 for ABC/3TC+LPV/r and ABC/3TC+ATV/r, and 0.89 for TDF/FTC/EVG/COBI. Efficiency, in terms of cost/efficacy, ranges from 7546 to 13,802 Euros per responder at 48 weeks, for ABC/3TC+EFV and TDF/FTC+RAL respectively.

CONCLUSION

Considering ART official prices, the most efficient regimen was ABC/3TC+EFV (AR), followed by the non-nucleoside containing PR (TDF/FTC/RPV and TDF/FTC/EFV). The sensitivity analysis confirms the robustness of these findings.

Some current issues in the design of HIV noninferiority trials

Since the introduction of protease inhibitors and their combination with two nucleoside reverse transcriptase inhibitors in tri-therapy, there has been a continuous improvement in the efficacy of antiretroviral treatments. Such combinations have been rendered even more effective by the introduction of non-nucleoside reverse transcriptase inhibitors and, more recently, integrase inhibitors. This progress has led to a move away from superiority designs towards noninferiority designs for randomized clinical trials for HIV. Noninferiority trials aim to demonstrate that a new regimen is no worse than the current standard. The methodological issues associated with such designs have been discussed, but recent HIV trials provide us with an opportunity to consider the choice of hypotheses. Recent HIV trials have been overpowered, due to the assumption of lower success rates than observed and the enrollment of a large number of patients. The use of stratified statistical methods for primary endpoint analysis, with sample size calculated by classical methods (without stratification), also increases the statistical power. Some HIV trials have a statistical power close to 99%. Surprisingly, the results of some previous studies or phase II trials are not taken into account when designing the corresponding phase III trials. We discuss alternative hypotheses and designs.

Resistance to HIV integrase strand transfer inhibitors: in vitro findings and clinical consequences

Three integrase strand transfer inhibitors have now been approved for the treatment of HIV infection, raltegravir, cobicistat-boosted elvitegravir, and dolutegravir. Each of these agents selects for unique signature mutations; however, there can be significant cross resistance among all three drugs when multiple mutations are present or are presented in the context of different genetic backgrounds such as non B-subtypes. Many of the mutations that are associated with integrase inhibitor resistance have a profound effect on integrase function and viral replication and thus, while only one or two mutations may be sufficient to impact susceptibility, virologic failure and treatment-associated resistance have been infrequent with all three drugs to date.

The combined anti-HIV-1 activities of emtricitabine and tenofovir plus the integrase inhibitor elvitegravir or raltegravir show high levels of synergy in vitro

Highly active antiretroviral therapy (HAART) involves combination treatment with three or more antiretroviral agents. The antiviral effects of combinations of emtricitabine (FTC) plus tenofovir (TFV) plus antiretroviral agents of all the major drug classes were investigated. Combinations of FTC and TFV with a nonnucleoside reverse transcriptase inhibitor (NNRTI) (efavirenz or rilpivirine) or with a protease inhibitor (PI) (atazanavir, lopinavir, or darunavir) showed additive to synergistic anti-HIV-1 activity. FTC-TFV with an HIV-1 integrase strand transfer inhibitor (INSTI) (elvitegravir or raltegravir) showed the strongest synergy. Anti-HIV-1 synergy suggests enhancement of individual anti-HIV-1 activities within cells that may contribute to potent treatment efficacy and open new areas of research into interactions between reverse transcriptase (RT) and integrase inhibitors.

The emerging profile of cross-resistance among the nonnucleoside HIV-1 reverse transcriptase inhibitors

Nonnucleoside reverse transcriptase inhibitors (NNRTIs) are widely used to treat HIV-1-infected individuals; indeed most first-line antiretroviral therapies typically include one NNRTI in combination with two nucleoside analogs. In 2008, the next-generation NNRTI etravirine was approved for the treatment of HIV-infected antiretroviral therapy-experienced individuals, including those with prior NNRTI exposure. NNRTIs are also increasingly being included in strategies to prevent HIV-1 infection. For example: (1) nevirapine is used to prevent mother-to-child transmission; (2) the ASPIRE (MTN 020) study will test whether a vaginal ring containing dapivirine can prevent HIV-1 infection in women; (3) a microbicide gel formulation containing the urea-PETT derivative MIV-150 is in a phase I study to evaluate safety, pharmacokinetics, pharmacodynamics and acceptability; and (4) a long acting rilpivirine formulation is under-development for pre-exposure prophylaxis. Given their widespread use, particularly in resource-limited settings, as well as their low genetic barriers to resistance, there are concerns about overlapping resistance between the different NNRTIs. Consequently, a better understanding of the resistance and cross-resistance profiles among the NNRTI class is important for predicting response to treatment, and surveillance of transmitted drug-resistance.

Safety and efficacy of coformulated efavirenz/emtricitabine/tenofovir single-tablet regimen in treatment-naive patients infected with HIV-1

Due to the differences between bioavailability of efavirenz (EFV) and tenofovir (TDF), the single-tablet regimen of EFV/emtricitabine (FTC)/TDF is not approved as initial antiretroviral therapy (ART) in Europe by the European Medical Agency. To compare clinical, immunological, and virological outcomes between co-formulated TDF/FTC+EFV and the co-formulated EFV/FTC/TDF single-tablet regimen in patients infected with HIV-1 naive to ART, the data of patients (n = 231) who initiated either TDF/FTC+EFV (n = 155) or EFV/FTC/TDF (n = 76) between January 1, 2007 and June 1, 2010 were analyzed. Changes from baseline to week 48 (TDF/FTC+EFV vs. EFV/FTC/TDF) in HIV plasma load (- 3.25 log vs. -3.32 log) and CD4+ T cell count (+180 vs. +138 cells/mm3) were similar in the two groups. Treatment discontinuation was recorded in 50 (22%) patients (40 on TDF/FTC+EFV and 10 on EFV/FTC/TDF, P = 0.03) but time to discontinuation did not differ between the two groups. Only patients on TDF/FTC+EFV discontinued treatment because of neurological symptoms. Virological failure occurred in 11 (4.7%) patients (seven on TDF/FTC+EFV and four on EFV/FTC/TDF, P = 0.75) with new resistance-associated mutations in five among the six with successful resistance genotype tests. Only baseline resistance-associated mutations was a risk factor for virological failure (P = 0.0146). These data show comparable outcomes between TDF/FTC+EFV or EFV/FTC/TDF used in patients infected with HIV-1 and not treated previously, consistent with a low rate of virological failure in the absence of pretreatment resistance. This would suggest that the European Medical Agency should approve co-formulated EFV/FTC/TDF single-tablet regimen for patients naive to ART.

Resistance analyses of integrase strand transfer inhibitors within phase 3 clinical trials of treatment-naive patients

The integrase (IN) strand transfer inhibitors (INSTIs), raltegravir (RAL), elvitegravir (EVG) and dolutegravir (DTG), comprise the newest drug class approved for the treatment of HIV-1 infection, which joins the existing classes of reverse transcriptase, protease and binding/entry inhibitors. The efficacy of first-line regimens has attained remarkably high levels, reaching undetectable viral loads in 90% of patients by Week 48; however, there remain patients who require a change in regimen due to adverse events, virologic failure with emergent resistance or other issues of patient management. Large, randomized clinical trials conducted in antiretroviral treatment-naive individuals are required for drug approval in this population in the US, EU and other countries, with the primary endpoint for virologic success at Week 48. However, there are differences in the definition of virologic failure and the evaluation of drug resistance among the trials. This review focuses on the methodology and tabulation of resistance to INSTIs in phase 3 clinical trials of first-line regimens and discusses case studies of resistance.

Connecting the dots: could microbial translocation explain commonly reported symptoms in HIV disease?

Microbial translocation within the context of HIV disease has been described as one of the contributing causes of inflammation and disease progression in HIV infection. HIV-associated symptoms have been related to inflammatory markers and sCD14, a surrogate marker for microbial translocation, suggesting a plausible link between microbial translocation and symptom burden in HIV disease. Similar pathophysiological responses and symptoms have been reported in inflammatory bowel disease. We provide a comprehensive review of microbial translocation, HIV-associated symptoms, and symptoms connected with inflammation. We identify studies showing a relationship among inflammatory markers, sCD14, and symptoms reported in HIV disease. A conceptual framework and rationale to investigate the link between microbial translocation and symptoms is presented. The impact of inflammation on symptoms supports recommendations to reduce inflammation as part of HIV symptom management. Research in reducing microbial translocation-induced inflammation is limited, but needed, to further promote positive health outcomes among HIV-infected patients.

Long-term treatment with raltegravir or efavirenz combined with tenofovir/emtricitabine for treatment-naive human immunodeficiency virus-1-infected patients: 156-week results from STARTMRK

BACKGROUND

We compared 3 years of antiretroviral therapy with raltegravir or efavirenz as part of a combination regimen in the ongoing STARTMRK study of treatment-naive patients infected with human immunodeficiency virus (HIV).

METHODS

Eligible patients with HIV-1 RNA (vRNA) levels >5000 copies/mL and without baseline resistance to efavirenz, tenofovir, or emtricitabine were randomized in a double-blind, noninferiority study to receive raltegravir or efavirenz, each combined with tenofovir/emtricitabine. Outcomes included viral suppression, adverse events, and changes from baseline metabolic parameters. Dual energy X-ray absorptiometry scans were obtained on a convenience sample of patients at prespecified time points to assess changes in body fat composition.

RESULTS

At week 156 counting noncompleters as failures, 212 (75.4%) of 281 versus 192 (68.1%) of 282 had vRNA levels <50 copies/mL in the raltegravir and efavirenz groups, respectively [Δ (95% CI) = 7.3% (-0.2, 14.7), noninferiority P < .001]. Mean changes from baseline CD4 count were 332 and 295 cells/mm³ in the raltegravir and efavirenz arms, respectively [Δ (95% CI) = 37 (4, 69)]. Consistent virologic and immunologic efficacy was maintained across prespecified demographic and baseline prognostic subgroups for both treatment groups. Fewer drug-related clinical adverse events (49% vs 80%; P < .001) occurred in raltegravir than efavirenz recipients, with discontinuations due to adverse events in 5% and 7%, respectively. Elevations in fasting lipid levels (including LDL- and HDL-cholesterol) were consistently lower in the raltegravir than efavirenz group (P < .005). Fat gain was 19% in 25 raltegravir recipients and 31% in 32 efavirenz recipients at week 156.

CONCLUSIONS

When combined with tenofovir/emtricitabine in treatment-naive patients, raltegravir produced durable viral suppression and immune restoration that was at least equivalent to efavirenz through 156 weeks of therapy. Both regimens were well tolerated, but raltegravir was associated with fewer drug-related clinical adverse events and smaller elevations in lipid levels. Clinical Trials Registration. NCT00369941.

Antiretroviral therapy: treatment-experienced individuals

Antiretroviral therapy (ART)-experienced individuals may choose to modify their regimens because of suboptimal virologic response, poor tolerability, convenience, or to minimize interactions with other medications or food. Constructing a new regimen for any of these reasons requires a thorough review of prior antiretroviral drug use and available drug resistance results. This article summarizes the strategies used in managing the ART-experienced individual who is considering a modification in therapy at the time of suboptimal virologic response or while virologically suppressed on a stable regimen.

Dolutegravir, the Second-Generation of Integrase Strand Transfer Inhibitors (INSTIs) for the Treatment of HIV

The integrase strand transfer inhibitors (INSTIs) are the newest antiretroviral class in the HIV treatment armamentarium. Dolutegravir (DTG) is the only second-generation INSTI with FDA approval (2013). It has potential advantages in comparison to first-generation INSTI’s, including unboosted daily dosing, limited cross resistance with raltegravir and elvitegravir, and a high barrier to resistance. Clinical trials have evaluated DTG as a 50-mg daily dose in both treatment-naïve and treatment-experienced, INSTI-naïve participants. In those treatment-naïve participants with baseline viral load <100,000 copies/mL, DTG combined with abacavir and lamivudine was non-inferior and superior to fixed-dose combination emtricitabine/tenofovir/efavirenz. DTG was also superior to the protease inhibitor regimen darunavir/ritonavir in treatment-naïve participants regardless of baseline viral load. Among treatment-experienced patients naïve to INSTI, DTG (50 mg daily) demonstrated both non-inferiority and superiority when compared to the first-generation INSTI raltegravir (400 mg twice daily) regardless of the background regimen. No phenotypically significant DTG resistance has been demonstrated in INSTI-naïve participant trials. The VIKING trials evaluated DTG’s ability to treat persons with HIV with prior INSTI exposure. VIKING demonstrated twice-daily DTG was more efficacious than daily dosing when treating participants receiving and failing first-generation INSTI regimens. DTG maintained potency against single mutations from any of the three major INSTI pathways (Y143, H155, Q148); however, the Q148 mutation with two or more additional mutations significantly reduced its potency. The long-acting formulation of DTG, GSK1265744LA, is the next innovation in this second-generation INSTI class, holding promise for the future of HIV prevention and treatment.

Impact of raltegravir on HIV-1 RNA and DNA forms following initiation of antiretroviral therapy in treatment-naive patients

OBJECTIVES

The rapid early-phase decay of plasma HIV-1 RNA during integrase inhibitor-based therapy is not fully understood. The accumulation of biologically active episomal HIV-1 cDNAs, following aborted integration, could contribute to antiviral potency in vivo.

METHODS

This prospective, controlled clinical observation study explored raltegravir's impact on the dynamics of HIV-1 RNA in plasma, and concentrations of total HIV-1 cDNA, episomal 2-long terminal repeat (LTR) circles and HIV-1 integrants in peripheral blood mononuclear cells (PBMC). Individuals starting therapy with two nucleoside reverse transcriptase inhibitors plus either raltegravir (raltegravir group; n = 10 patients) or boosted protease inhibitor/non-nucleoside reverse transcriptase inhibitor (control group; n = 10 patients) were followed for 48 weeks.

RESULTS

Suppression of HIV-1 RNA (<50 copies/mL) was reached earlier (5/10 versus 0/10 at week 4; 8/10 versus 4/10 at week 12) on raltegravir. Significant total HIV-1 cDNA reductions in PBMC were reached by day 99 and persisted until day 330, with median factors of decrease of 7.2 and 8.9, respectively. Broad inter-individual variations, yet no treatment-associated differences, were noted for HIV-1 cDNA concentrations. Despite reductions in HIV-1 RNA (∼3 log) and total HIV-1 cDNA (∼1 log), concentrations of integrants and 2-LTR circles remained largely unchanged.

CONCLUSIONS

These results extend the previously reported early benefit of raltegravir on the decline of plasma viraemia to treatment-naive patients. The modest treatment-associated, yet group-independent, decline in total HIV-1 cDNA load and the lack of significant changes in integrated and episomal HIV-1 cDNA suggest that most integrated DNA is archival and targeting of HIV reservoirs other than PBMC may underlie beneficial effects of raltegravir.

Virological outcome at week 48 of three recommended first-line regimens using ultrasensitive viral load and plasma drug assay

OBJECTIVES

To describe the virological and pharmacological outcomes of three different recommended once-daily first-line regimens in a cross-sectional analysis within an observational cohort using ultra-sensitive HIV quantification.

PATIENTS AND METHODS

We enrolled all HIV-1-infected patients who initiated tenofovir/emtricitabine with efavirenz, darunavir/ritonavir or atazanavir/ritonavir as a first-line regimen between 1 November 2010 and 30 June 2012. An ultrasensitive viral load (VL) assay was performed and plasma drug concentrations at 24 h (C24) were determined at Week (W) 4, W12, W24, W36 and W48.

RESULTS

Sixty patients initiated efavirenz, 81 darunavir/ritonavir and 27 atazanavir/ritonavir. A higher proportion of patients with a VL >100 000 copies/mL received darunavir/ritonavir (P = 0.022). At W48, 89%, 85% and 88% of the patients had a VL <50 copies/mL, 69%, 73% and 79% had a VL <20 copies/mL and 45%, 48% and 54% had a VL <1 copy/mL using the ultrasensitive assay in the efavirenz, darunavir/ritonavir and atazanavir/ritonavir groups, respectively. Patients with a detectable VL signal at W48 had a higher baseline VL than those with no detectable VL signal (P = 0.0001). A total of 92%, 93% and 91% of the efavirenz, darunavir and atazanavir C24 values were above the respective effective cut-offs.

CONCLUSIONS

In this observational cohort, the choice of the regimen was related to the physicians' preferences and the patients' characteristics. The proportion of patients reaching VL <1 copy/mL at W48 was similar in the three regimens and was not associated with drug concentrations.

French 2013 guidelines for antiretroviral therapy of HIV-1 infection in adults

Introduction

These guidelines are part of the French Experts’ recommendations for the management of people living with HIV/AIDS, which were made public and submitted to the French health authorities in September 2013. The objective was to provide updated recommendations for antiretroviral treatment (ART) of HIV-positive adults. Guidelines included the following topics: when to start, what to start, specific situations for the choice of the first session of antiretroviral therapy, optimization of antiretroviral therapy after virologic suppression, and management of virologic failure.

Methods

Ten members of the French HIV 2013 expert group were responsible for guidelines on ART. They systematically reviewed the most recent literature. The chairman of the subgroup was responsible for drafting the guidelines, which were subsequently discussed within, and finalized by the whole expert group to obtain a consensus. Recommendations were graded for strength and level of evidence using predefined criteria. Economic considerations were part of the decision-making process for selecting preferred first-line options. Potential conflicts of interest were actively managed throughout the whole process.

Results

ART should be initiated in any HIV-positive person, whatever his/her CD4 T-cell count, even when >500/mm³. The level of evidence of the individual benefit of ART in terms of mortality or progression to AIDS increases with decreasing CD4 cell count. Preferred initial regimens include two nucleoside reverse transcriptase inhibitors (tenofovir/emtricitabine or abacavir/lamivudine) plus a non-nucleoside reverse transcriptase inhibitor (efavirenz or rilpivirine), or a ritonavir-boosted protease inhibitor (atazanavir or darunavir). Raltegravir, lopinavir/r, and nevirapine are recommended as alternative third agents, with specific indications and restrictions. Specific situations such as HIV infection in women, primary HIV infection, severe immune suppression with or without identified opportunistic infection, and person who injects drugs are addressed. Options for optimization of ART once virologic suppression is achieved are discussed. Evaluation and management of virologic failure are described, the aim of any intervention in such situation being to reduce plasma viral load to <50 copies/ml.

Conclusion

These guidelines recommend that any HIV-positive individual should be treated with ART. This recommendation was issued both for the patient’s own sake and for promoting treatment as prevention.

Prevalence of primary resistance mutations to integrase inhibitors in treatment-naïve and -experienced patients infected with B and non-B HIV-1 variants

BACKGROUND

Raltegravir (RAL) constitutes the first available integrase strand transfer inhibitor (INSTI) available in clinical practice. Three independent pathways have been described to confer resistance to RAL. Secondary mutations with little effect on INSTI susceptibility and additional substitutions with an uncertain role have also been described especially in HIV-1 non-B variants.

METHODS

We evaluated the prevalence of primary, secondary, and additional resistance mutations to INSTIs in patients naïve to RAL or elvitegravir (EGV) carrying different HIV-1 variants.

RESULTS

A total of 83 patients infected by B HIV-1 subtype (64%) or non-B HIV-1 variants (36%) were evaluated. No primary mutations to RAL or EGV were found in the inte-grase sequences analyzed. Secondary mutations were detected in only 5 patients. Additional mutations were found in both in B and non-B variants. According to the geno2pheno algorithm, some of the secondary mutations detected (L74V, E138K, G163RS, and V151I) have been associated with a reduced estimated susceptibility to RAL and only the E138K mutation has been associated with a decreased estimated susceptibility to EGV. No virological failure was observed after RAL was administrated in 17 patients carrying 1 or more additional substitutions in the absence of primary or secondary mutations.

CONCLUSIONS

No primary resistance mutations to INSTI were found in treatment-naïve or -experienced patients infected with B or non-B HIV-1 variants. The vast majority had some polymorphic and non-polymorphic substitutions; however response to RAL was excellent in patients who harbored one or more of these mutations. We could not identify any clinical factors associated with the presence of any of these mutations.

Addition of E138K to R263K in HIV integrase increases resistance to dolutegravir, but fails to restore activity of the HIV integrase enzyme and viral replication capacity

BACKGROUND

The results of several clinical trials suggest that the integrase inhibitor dolutegravir may be less prone than other drugs to the emergence of HIV drug resistance mutations in treatment-naive patients. We have shown that the R263K mutation commonly emerged during tissue culture selection studies with dolutegravir and conferred low levels of resistance to this drug while simultaneously diminishing both HIV replication capacity and integrase enzymatic activity. E138K has been identified as a secondary mutation for dolutegravir in selection studies and has also been observed as a secondary mutation in the clinic for the integrase inhibitors raltegravir and elvitegravir.

METHODS

We used biochemical cell-free strand-transfer assays and tissue culture assays to characterize the effects of the E138K/R263K combination of mutations on resistance to dolutegravir, integrase enzyme activity and HIV-1 replication capacity.

RESULTS

We show here that the addition of the E138K substitution to R263K increased the resistance of HIV-1 to dolutegravir but failed to restore viral replication capacity, integrase strand-transfer activity and integration within cellular DNA. We also show that the addition of E138K to R263K did not increase the resistance to raltegravir or elvitegravir. The addition of the E138K substitution to R263K was also less detrimental to integrase strand-transfer activity and integration than a different secondary mutation at position H51Y that had also been selected in culture.

CONCLUSIONS

The E138K substitution failed to restore the defect in viral replication capacity that is associated with R263K, confirming previous selection studies that failed to identify compensatory mutation(s) for the latter primary mutation. This study suggests that the R263K resistance pathway may represent an evolutionary dead end for HIV in treatment-naive individuals who are treated with dolutegravir and will need to be confirmed by the long-term use of dolutegravir in the clinic.

Urinary eicosanoid metabolites in HIV-infected women with central obesity switching to raltegravir: an analysis from the women, integrase, and fat accumulation trial

Chronic inflammation is a hallmark of HIV infection. Eicosanoids reflect inflammation, oxidant stress, and vascular health and vary by sex and metabolic parameters. Raltegravir (RAL) is an HIV-1 integrase inhibitor that may have limited metabolic effects. We assessed urinary F₂-isoprostanes (F₂-IsoPs), prostaglandin E₂ (PGE-M), prostacyclin (PGI-M), and thromboxane B₂ (TxB₂) in HIV-infected women switching to RAL-containing antiretroviral therapy (ART). Thirty-seven women (RAL = 17; PI/NNRTI = 20) with a median age of 43 years and BMI 32 kg/m² completed week 24. TxB₂ increased in the RAL versus PI/NNRTI arm (+0.09 versus −0.02; P = 0.06). Baseline PGI-M was lower in the RAL arm (P = 0.005); no other between-arm cross-sectional differences were observed. In the PI/NNRTI arm, 24-week visceral adipose tissue change correlated with PGI-M (rho = 0.45; P = 0.04) and TxB₂ (rho = 0.44; P = 0.005) changes, with a trend seen for PGE-M (rho = 0.41; P = 0.07). In an adjusted model, age ≥ 50 years (N = 8) was associated with increased PGE-M (P = 0.04). In this randomized trial, a switch to RAL did not significantly affect urinary eicosanoids over 24 weeks. In women continuing PI/NNRTI, increased visceral adipose tissue correlated with increased PGI-M and PGE-M. Older age (≥50) was associated with increased PGE-M. Relationships between aging, adiposity, ART, and eicosanoids during HIV-infection require further study.

When can HIV clinical trials detect treatment effects on drug resistance?

Methods of sampling patients for resistance testing, and statistical analyses of HIV drug resistance, have not been standardised in HIV clinical trials. We analysed methods of genotyping and rates of treatment-emergent drug resistance from 27 clinical trials identified from a MEDLINE search. Sample size calculations were conducted using NQUERY software, assuming 5% significance level, 80% power and 1:1 randomisation. The percentage of patients with treatment-emergent IAS-USA mutations after 96 weeks ranged from 1.8% to 9.1% for first-line 2NRTI/NNRTI treatments, 0.6% to 6.3% for first-line 2NRTI/PI/r treatments and 0.0% to 2.0% in switch trials of boosted PIs. The prevalence of drug resistance was higher in trials with no screening for drug resistance at baseline, where the HIV RNA cut-off for genotyping was >50 copies/mL, where patients were tested for drug resistance after discontinuation of treatment, and where follow-up times were 96 weeks or longer. HIV clinical trials could be designed to detect differences in the risk of HIV drug resistance between treatments, as an analysis supporting HIV RNA suppression as the primary endpoint. However, this would require a standardised approach, with intent-to-treat analyses, testing of all samples with HIV RNA>50 copies/mL and genotyping after drug discontinuation.

Metabolic and body composition effects of newer antiretrovirals in HIV-infected patients

In the absence of a cure, HIV-infected patients are being successfully treated with antiretroviral therapies (ART) and living longer. Indeed, an increasing number of HIV-infected patients are living beyond the age of 50 years, and in that regard, the use of ART has transformed HIV into a chronic medical condition. As more HIV-infected patients are virologically controlled and living longer, the trajectory of disease morbidity has shifted, however, primarily from opportunistic infections and immune dysfunction to metabolic complications. Evidence suggests that HIV-infected patients acquire significant metabolic risks, including lipodystrophic changes, subclinical atherosclerosis, and insulin resistance. The etiology of these metabolic complications specifically in HIV-infected patients is not entirely clear but may be related to a complex interaction between long-term consequences of infection and HIV itself, chronic use of antiretrovirals, and underlying inflammatory processes. Previous classes of ART, such as protease inhibitors (PIs) and reverse transcriptase inhibitors, have been implicated in altering fat redistribution and lipid and glucose homeostasis. Advances in drug development have introduced newer ART with strategies to target novel mechanisms of action and improve patient adherence with multi-class drug combinations. In this review, we will focus on these newer classes of ART, including selected entry inhibitors, integrase inhibitors, and multi-class drug combinations, and two newer PIs, and the potential of these newer agents to cause metabolic complications in HIV-infected patients. Taken together, further reduction of morbidity in HIV-infected patients will require increasing awareness of the deleterious metabolic complications of ART with subsequent management to mitigate these risks.

Integrase strand transfer inhibitors in the management of HIV-positive individuals

The use of highly active antiretroviral therapy against human immunodeficiency virus (HIV) can lead to rare instances of treatment failure and the emergence of drug resistance. HIV drug-resistant strains are archived in cellular reservoirs, and this can exclude the future efficacy of drugs or drug classes against which resistance has emerged. In addition, drug-resistant viruses can be transmitted between individuals. HIV drug resistance has been countered through the constant development of new antiretroviral drugs. Integrase strand transfer inhibitors, that actively block the integration of the HIV genome into the host DNA, represent the most recent antiretroviral drugs. Of these, raltegravir, elvitegravir, and dolutegravir are the only integrase strand transfer inhibitors that have been approved for human therapy by the US Food and Drug Administration. Dolutegravir is unique in its ability to seemingly evade HIV drug resistance in treatment-naïve individuals. Here, we review the use of integrase strand transfer inhibitors in the management of HIV, focusing on HIV resistance.

Efficacy of 400 mg efavirenz versus standard 600 mg dose in HIV-infected, antiretroviral-naive adults (ENCORE1): a randomised, double-blind, placebo-controlled, non-inferiority trial

BACKGROUND

The optimum dose of key antiretroviral drugs is often overlooked during product development. The ENCORE1 study compared the efficacy and safety of reduced dose efavirenz with standard dose efavirenz in combination with tenofovir and emtricitabine as first-line treatment for HIV infection. An effective and safe reduced dose could yield meaningful cost savings.

METHODS

ENCORE1 is a continuing non-inferiority trial in HIV-1-infected antiretroviral-naive adults in 38 clinical sites in 13 countries. Participants (plasma HIV-RNA >1000 log10 copies per mL, CD4 T-cell count 50-500 cells per μL) were randomly assigned by a computer-generated sequence with a blocking factor of four (stratified by clinical site and by screening viral load) to receive tenofovir plus emtricitabine with either a reduced daily dose (400 mg) or a standard dose (600 mg) of efavirenz. Participants, physicians, and all other trial staff were masked to treatment group. The primary endpoint was the difference in proportions of participants with plasma HIV-RNA of less than 200 copies per mL at 48 weeks. Treatment groups were regarded as non-inferior if the lower limit of the 95% CI for the difference in viral load was less than -10% by modified intention-to-treat analysis. Adverse events were summarised by treatment. This trial is registered with ClinicalTrials.gov, number NCT01011413.

FINDINGS

The modified intention-to-treat analysis consisted of 630 patients (efavirenz 400=321; efavirenz 600=309). 32% were women; 37% were African, 33% were Asian, and 30% were white. The mean baseline CD4 cell count was 273 cells per μL (SD 99) and median plasma HIV-RNA was 4·75 log10 copies per mL (IQR 0·88). The proportion of participants with a viral load below 200 copies per mL at week 48 was 94·1% for efavirenz 400 mg and 92·2% for 600 mg (difference 1·85%, 95% CI -2·1 to 5·79). CD4 T-cell counts at week 48 were significantly higher for the 400 mg group than for the 600 mg group (mean difference 25 cells per μL, 95% CI 6-44; p=0·01). We recorded no difference in grade or number of patients reporting adverse events (efavirenz 400=89·1%, efavirenz 600=88·4%; difference 0·75%, 95% CI -4·19 to 5·69; p=0·77). Study drug-related adverse events were significantly more frequent in the 600 mg group than in the 400 mg group (146% [47] vs 118 [37]), difference -10·5%, 95% CI -18·2 to -2·8; p=0·01) and significantly fewer patients with these events stopped treatment (400 mg=6 [2%], 600 mg=18 [6%], difference -3·96%, 95% CI -6·96 to -0·95; p=0·01).

INTERPRETATION

Our findings suggest that a reduced dose of 400 mg efavirenz is non-inferior to the standard dose of 600 mg, when combined with tenofovir and emtricitabine during 48 weeks in ART-naive adults with HIV-1 infection. Adverse events related to the study drug were more frequent with 600 mg efavirenz than with 400 mg. Lower dose efavirenz should be recommended as part of routine care.

FUNDING

Bill & Melinda Gates Foundation, University of New South Wales.

Lipid levels and changes in body fat distribution in treatment-naive, HIV-1-Infected adults treated with rilpivirine or Efavirenz for 96 weeks in the ECHO and THRIVE trials

BACKGROUND

Pooled ECHO/THRIVE lipid and body fat data are presented from the ECHO (Efficacy Comparison in Treatment-Naïve, HIV-Infected Subjects of TMC278 and Efavirenz) and THRIVE (TMC278 Against HIV, in a Once-Daily Regimen Versus Efavirenz) trials.

METHODS

We assessed the 96-week effects on lipids, adverse events (AEs), and body fat distribution (dual-energy x-ray absorptiometry) of rilpivirine (RPV) and EFV plus 2 nucleoside/nucleotide reverse transcriptase inhibitors (N[t]RTIs) in treatment-naive adults infected with human immunodeficiency virus type 1 (HIV-1).

RESULTS

Rilpivirine produced minimal changes in total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides. Compared with RPV, EFV significantly (P < .001) increased lipid levels. Decreases in the TC/HDL-C ratio were similar with RPV and EFV. Background N[t]RTI affected RPV-induced lipid changes; all levels increased with zidovudine/lamivudine (3TC) and abacavir/3TC (except triglycerides, which were unchanged). With emtricitabine/tenofovir, levels of HDL-C were increased, TC and LDL-C were unchanged, and triglycerides were decreased. With EFV, lipid levels increased in each N[t]RTI subgroup (except triglycerides were unchanged with abacavir/3TC). Fewer (P < .001) RPV-treated patients than EFV-treated patients had TC, LDL-C, and triglyceride levels above National Cholesterol Education Program cutoffs. More RPV- than EFV-treated patients had HDL-C values below these cutoffs (P = .02). Dyslipidemia AEs were less common with RPV than with EFV. Similar proportions of patients had a ≥10% decrease in limb fat (16% with RPV and 17% with EFV). Limb fat was significantly (P < .001) increased to a similar extent (by 12% with RPV and 11% with EFV). At week 96, patients receiving zidovudine/3TC had lost limb fat, and those receiving emtricitabine/tenofovir had gained it.

CONCLUSIONS

Over the course of 96 weeks, RPV-based therapy was associated with lower increases in lipid parameters and fewer dyslipidemia AEs than EFV-based treatment. Body fat distribution changes were similar between treatments. The N[t]RTI regimen affected lipid and body fat distribution changes.