Evolution of blood-associated HIV-1 DNA levels after 48 weeks of switching to atazanavir/ritonavir+lamivudine dual therapy versus continuing triple therapy in the randomized AtLaS-M trial

Evaluation of HIV-DNA and residual viremia levels through week 96 in HIV-infected individuals who continue a two-drug or switch to a three-drug integrase strand transfer inhibitor based regimen

OBJECTIVES

To investigate HIV-DNA and residual viremia (RV) levels over 96 weeks (W96) in virologically suppressed HIV-1 infected individuals enrolled in the Be-OnE Study. Individuals were randomized to continue a two-drug regimen with dolutegravir (DTG) plus one RTI or to switch to elvitegravir/cobicistat/emtricitabine/tenofovir-alafenamide (E/C/F/TAF).

STUDY DESIGN

Total HIV-DNA and RV were evaluated at baseline, W48 and W96 with ddPCR technique. Potential relationships between viro-immunological parameters and between/within arms were also assessed.

RESULTS

Median (IQR) HIV-DNA was 2247 (767;4268), 1587 (556;3543) and 1076 (512;2345) copies/10⁶ CD4+T-cells at baseline, W48 and at W96, respectively, while RV was 3 (1;5), 4 (1;9) and 2 (2;4) copies/mL, without significant differences between arms. A significant reduction in HIV-DNA and in RV from baseline to W96 was observed in the E/C/F/TAF-arm (HIV-DNA: -285 [-2257;-45], p=0.010; RV: (-1 [-3;0], p=0.007). In the DTG+1RTI-arm, HIV-DNA and RV levels remained stable (HIV-DNA: -549 [-2269;+307], p=0.182; RV: (-1 [-3;+1], p=0.280). For both HIV-DNA and RV, no significant changes were found overtime between the arms. A positive correlation was found between baseline HIV-DNA and HIV-DNA at W96 (E/C/F/TAF: rs=0.726, p=0.0004; DTG+1RTI: rs=0.589, p=0.010). In general, no significant correlations were found between HIV-DNA, RV and immunological parameters overtime.

CONCLUSIONS

In virologically suppressed individuals, a small reduction in the HIV-DNA and HIV-RNA levels was found from baseline to W96 in individuals who switched to the E/C/F/TAF arm compared to those who remained under DTG+1RTI. However, no significant differences were found in the changes of HIV-DNA and HIV-RNA between the two arms over time.

Two-drug regimens for HIV treatment

Combination therapy with three antiretroviral agents has been integral to successful HIV-1 treatment since 1996. Although the efficacy, adverse effects, and toxicities of contemporary three-drug regimens have improved, even the newest therapies have potential adverse effects. The use of two-drug regimens is one way to reduce lifetime exposure to antiretroviral drugs while maintaining the benefits of viral suppression. Multiple large, randomised trials have shown the virological non-inferiority of certain two-drug regimens versus three-drug comparators, including adverse effect differences that reflect known profiles of the antiretroviral drugs in the respective regimens. Two-drug combinations are now recommended in treatment guidelines and include the first long-acting antiretroviral regimen for the treatment of HIV-1. Recommended two-drug regimens differ in their risks for, and factors associated with, virological failure and emergent resistance. The tolerability, safety, metabolic profiles, and drug interactions of two-drug regimens also vary by the constituent drugs. No current two-drug regimen is recommended for people with chronic hepatitis B virus as none include tenofovir. Two-drug regimens have increased options for individualised care.

Immunological and inflammatory changes after simplifying to dual therapy in virologically suppressed HIV-infected patients through week 96 in a randomized trial

OBJECTIVES

To evaluate whether simplification of antiretroviral treatment to dual therapy (DT) negatively impacts immune recovery (IR), immune activation and inflammation (IA/I), and HIV reservoir.

METHODS

An open-label, single-centre, randomized controlled trial conducted in adult virologically suppressed HIV-infected patients on triple therapy (TT) with elvitegravir-cobicistat, emtricitabine and tenofovir alafenamide or dolutegravir (DTG), abacavir, and lamivudine (3TC). Participants were randomized to continue TT or switch to DTG, or darunavir/cobicistat (DRVc) plus 3TC. IR was assessed by CD4⁺/CD8⁺ ratio at 48 and 96 weeks. Changes in immune activation, proliferation, exhaustion, senescence, and apoptosis in CD4⁺ and CD8⁺ T cells, plasma sCD14, hsCRP, D-dimers, β2-microglobulin, IL-6, TNF-α and IP-10 levels, cell-associated HIV-DNA (CA-DNA), and unspliced HIV-RNA (usRNA) were also analysed.

RESULTS

One hundred and fifty-one participants were enrolled. Fourteen patients did not complete the follow up. In the ITT and PP analysis, the IR was similar between the treatment arms. In the ITT analysis, the median increase in CD4⁺/CD8⁺ ratio was 0.10, 0.04, and 0.07 at week 48, and 0.09, 0.05, and 0.08 at week 96 for TT, DTG/3TC, and DRVc/3TC, respectively. After adjusting for confounding factors, the slopes of changes in CD4⁺/CD8⁺ ratio over time were independent of treatment (F = 1.699; p = 0.436) and related only to baseline values (F = 756.871; p = 0.000). There were no differences in IA/I, CA-DNA, or usRNA between treatment arms.

DISCUSSION

Both IR and IA/I, CA-DNA, and usRNA were similar in the three treatment groups, regardless of maintaining TT or simplifying to DTG/3TC or DRVc/3TC in virologically suppressed HIV-infected patients.

Two-Drug Regimens for HIV-Current Evidence, Research Gaps and Future Challenges

During the last 30 years, antiretroviral treatment (ART) for human immunodeficiency virus (HIV) infection has been continuously evolving. Since 1996, three-drug regimens (3DR) have been standard-of-care for HIV treatment and are based on a protease inhibitor (PI) or a non-nucleoside reverse transcriptase inhibitor (NNRTI) plus two nucleoside reverse transcriptase inhibitors (NRTIs). The effectiveness of first-generation 3DRs allowed a dramatic increase in the life expectancy of HIV-infected patients, although it was associated with several side effects and ART-related toxicities. The development of novel two-drug regimens (2DRs) started in the mid-2000s in order to minimize side effects, reduce drug-drug interactions and improve treatment compliance. Several clinical trials compared 2DRs and 3DRs in treatment-naïve and treatment-experienced patients and showed the non-inferiority of 2DRs in terms of efficacy, which led to 2DRs being used as first-line treatment in several clinical scenarios, according to HIV clinical guidelines. In this review, we summarize the current evidence, research gaps and future prospects of 2DRs.

Quantification of Total HIV DNA as a Marker to Measure Viral Reservoir: Methods and Potential Implications for Clinical Practice

The focus of this review is to examine the importance of quantifying total HIV DNA to target the HIV reservoir and the clinical implications and challenges involved in its future application in clinical practice. Despite intrinsic limitations, the quantification of total HIV DNA is currently the most widely used marker for exploring the HIV reservoir. As it allows estimating all forms of HIV DNA in the infected cells, total HIV DNA load is the biomarker of the HIV reservoir that provides most of the insights into HIV pathogenesis. The clinical role of total HIV-DNA in both untreated and treated patients is extensively supported by important lines of evidence. Thus, predictive models that include total HIV DNA load together with other variables could constitute a prognostic tool for use in clinical practice. To date, however, this marker has been primarily used in experimental evaluations. The main challenge is technical. Although the implementation of droplet digital PCR could improve analytical performance over real-time PCR, the lack of standardization has made cross-comparisons of the data difficult. An effort by investigators to compare protocols is needed. Furthermore, the main effort now should be to involve the biomedical industry in the development of certified assays for in vitro diagnostics use.

Efficacy and durability of two- vs. three-drug integrase inhibitor-based regimens in virologically suppressed HIV-infected patients: Data from real-life ODOACRE cohort

OBJECTIVES

The aim of the present study was to compare the efficacy and durability of treatment switch to two-drug (2DR) vs. three-drug (3DR) integrase inhibitor (InSTI)-based regimens in a real-life setting.

METHODS

Within the ODOACRE cohort, we selected adult patients with HIV RNA < 50 copies/mL switching to an InSTI-based 2DR or 3DR. Survival analyses were performed to estimate the probability of virological failure (VF, defined as one HIV RNA > 1000 copies/mL or two consecutive HIV RNA > 50 copies/mL) and treatment discontinuation (TD, defined as any modification, intensification or interruption of the regimen), and to evaluate their predictors.

RESULTS

Overall, 1666 patients were included, of whom 1334 (80%) were treated with a 3DR (19.9%, 25.0% and 55.1% elvitegravir-, raltegravir- and dolutegravir-based, respectively) and 332 (20%) with a 2DR (79.2% dolutegravir + lamivudine and 20.8% dolutegravir + rilpivirine). Over a median (interquartile range) follow-up of 100 (52-150) weeks, 52 (3.1%) patients experienced VF with an incidence of 1.5/100 person-year of follow-up (PYFU). The estimated 96-week probability of VF was similar for the 2DR and 3DR groups (2.3% vs. 2.8%, P = 0.53), but it was higher for elvitegravir (4.9%) and raltegravir (5.0%) than for dolutegravir (1.5%) (P = 0.04). Four hundred (24%) patients discontinued their InSTI-based regimen, with an incidence of 11.3/100 PYFU. At 96 weeks, 3DRs showed a higher probability of TD for any reason (20.6% vs. 11.2%, P < 0.001) and TD for toxicity (9.0% vs. 6.6%, P = 0.02) when compared with 2DRs. A higher risk of TD for central nervous system toxicity was observed for dolutegravir than for elvitegravir and raltegravir (4.0% vs. 2.5% vs. 0.6%, P = 0.005).

CONCLUSIONS

In virologically suppressed HIV-infected patients, 2DRs showed an efficacy similar to 3DRs but with better tolerability.

Characterization of viral rebounds on dual etravirine/raltegravir maintenance therapy (ANRS-163 ETRAL trial)

BACKGROUND

The ANRS-163 ETRAL trial, a switch study to an etravirine 200 mg/raltegravir 400 mg twice-daily regimen in 165 patients with HIV-1 infection, showed durable efficacy until Week 96. The aim of this work was to investigate in detail the virological rebounds (VRs), defined as at least one plasma HIV viral load (VL) >50 copies/mL.

METHODS

Quantification of HIV-DNA level was assessed at baseline, Week 48 and Week 96 (n = 157). VLs were measured in seminal plasma at Week 48 (n = 26). Genotypic resistance testing by ultra-deep sequencing (UDS) for reverse transcriptase (RT) and integrase regions was performed at baseline and at the time of VR.

RESULTS

In this study, 19 patients experienced VR, with 2 patients having virological failure (VF; two consecutive VLs >50 copies/mL). For the first patient with VF, UDS detected minority resistant variants only in RT (K103N, 9.6%; Y181C, 4.9%) at baseline. Some RT variants became dominant at VF (K101E, 86.3%; Y181C, 100.0%; G190A, 100.0%) and others emerged in integrase (Y143C, 2.4%; Q148R, 6.2%; N155H, 18.8%). For the second patient with VF, neither RT nor integrase mutations were detected at baseline and VF. Median HIV-DNA level was similar at baseline, Week 48 and Week 96 (2.17, 2.06 and 2.11 log10 copies/106 cells, respectively). Only one patient had a detectable seminal HIV VL (505 copies/mL).

CONCLUSIONS

The dual etravirine/raltegravir regimen as maintenance therapy was effective and the emergence of mutations in cases of VF was similar to that seen in other dual-regimen studies. No HIV-DNA level modification was evidenced by Week 96.

HIV-DNA undetectability during chronic HIV infection: frequency and predictive factors

BACKGROUND

HIV-DNA is a marker of HIV reservoirs. Objectives of the study were to determine prevalence of HIV-DNA < 100 copies/106 PBMCs in blood and to identify factors associated with this in a cohort of HIV-1-infected subjects treated with ART and with undetectable viral load (VL).

METHODS

This was a cross-sectional study on chronic HIV-1-infected people living with HIV (PLWH) followed up at the Department of Infectious Diseases of San Raffaele Scientific Institute on current ART without change for 12 months, with available pre-ART HIV-RNA and with undetectable VL for ≥12 months. HIV-DNA was amplified and quantified by real-time PCR (ABI Prism 7900); limit of detectability was 100 copies/106 PBMCs. Logistic regression was used to identify predictive factors for HIV-DNA < 100 copies/106 PBMCs.

RESULTS

Four hundred and sixty-eight PLWH were considered in the analyses, 119 (25%) with HIV-DNA < 100 copies/106 PBMCs. At multivariate analysis, we found that PLWH with lower zenith HIV-RNA, higher nadir CD4 and a shorter time between HIV diagnosis and ART start were more likely to have HIV-DNA < 100 copies/106 PBMCs, after adjustment for age, gender, calendar year of ART start, type of current ART regimen, percentage time spent with undetectable VL since ART start, current CD4 and CD4/CD8 ratio.

CONCLUSIONS

In our chronic PLWH on virological suppression for 4 years, the prevalence of HIV-DNA < 100  copies/106 PBMCs was found to be 25%. Lower zenith HIV-RNA, shorter time between HIV diagnosis and starting ART and higher CD4 nadir were independently associated with low HIV-DNA.

Risks and benefits of reducing the number of drugs to treat HIV-1 infection

Introduction: Despite the efficacy and safety of antiretroviral therapy, new treatment options are needed to address the concerns of patients and physicians regarding long-term toxicities, costs, and convenience of lifelong antiretroviral therapy. To achieve this goal, one strategy is to reduce the number of drugs in the antiretroviral regimen.Areas covered: We review the recent evidence on the efficacy and safety of reduced drug regimens and their potential risks and benefits. There is currently strong evidence showing that some two-drug regimens have a comparable efficacy and short-term safety compared to standard three-drug regimens. The fixed-dose combination of dolutegravir/lamivudine is already an alternative for many treatment-naïve and virologically suppressed HIV-1 infected adults supported by large randomized clinical trials. The co-formulation dolutegravir plus rilpivirine is also a switch strategy for maintenance therapy. Long-acting injectable cabotegravir plus rilpivirine has already regulatory approval, and islatravir plus doravirine is an expected option in the near future. Some two-drug regimens have not been as successful.Expert opinion: Long-term safety issues of these two-drug regimens remain to be determined, but with the overwhelming evidence available in virological control and short-term safety, the potential benefits of some of these two-drug regimens appear to outweigh the risks.

Do Combination Antiretroviral Therapy Regimens for HIV Infection Feature Diverse T-Cell Phenotypes and Inflammatory Profiles?

Immune abnormalities featuring HIV infection persist despite the use of effective combination antiretroviral therapy (cART) and may be linked to the development of noninfectious comorbidities. The aim of the present narrative, nonsystematic literature review is to understand whether cART regimens account for qualitative differences in immune reconstitution. Many studies have reported differences in T-cell homeostasis, inflammation, coagulation, and microbial translocation parameters across cART classes and in the course of triple vs dual regimens, yet such evidence is conflicting and not consistent. Possible reasons for discrepant results in the literature are the paucity of randomized controlled clinical trials, the relatively short follow-up of observational studies, the lack of clinical validation of the numerous inflammatory biomarkers utilized, and the absence of research on the effects of cART in tissues. We are currently thus unable to establish if cART classes and regimens are truly accountable for the differences observed in immune/inflammation parameters in different clinical settings. Questions still remain as to whether an early introduction of cART, specifically in the acute stage of disease, or newer drugs and novel dual drug regimens are able to significantly impact the quality of immune reconstitution and the risk of disease progression in HIV-infected subjects.

Atazanavir/ritonavir with lamivudine as maintenance therapy in virologically suppressed HIV-infected patients: 96 week outcomes of a randomized trial

Objectives

To investigate the long-term safety and efficacy of a treatment switch to dual ART with atazanavir/ritonavir + lamivudine versus continuing a standard regimen with atazanavir/ritonavir + 2NRTI in virologically suppressed patients.

Methods

ATLAS-M is a 96 week open-label, randomized, non-inferiority (margin -12%) trial enrolling HIV-infected adults on atazanavir/ritonavir + 2NRTI, with stable HIV-RNA <50 copies/mL and CD4 counts >200 cells/mm3. At baseline, patients were randomized 1:1 to switch to atazanavir/ritonavir + lamivudine or to continue the previous regimen. Here, we report the 96 week efficacy and safety data. The study was registered with ClinicalTrials.gov, number NCT01599364.

Results

Overall, 266 subjects were enrolled (133 in each arm). At 96 weeks, in the ITT population, patients free of treatment failure totalled 103 (77.4%) with atazanavir/ritonavir + lamivudine and 87 (65.4%) with triple therapy (difference +12.0%, 95% CI +1.2/+22.8, P = 0.030), demonstrating the superiority of dual therapy. Two (1.5%) and 9 (6.8%) virological failures occurred in the dual-therapy arm and the triple-therapy arm, respectively, without development of resistance to any study drug. Clinical adverse events occurred at similar rates in both arms. A higher frequency of grade 3-4 hyperbilirubinemia (66.9% versus 50.4%, P = 0.006) and hypertriglyceridaemia (6.8% versus 1.5%, P = 0.031) occurred with dual therapy, although this never led to treatment discontinuation. A significant improvement in renal function and lumbar spine bone mineral density occurred in the dual-therapy arm. The evolution of CD4, HIV-DNA levels and neurocognitive performance was similar in both arms.

Conclusions

In this randomized study, a treatment switch to atazanavir/ritonavir + lamivudine was superior over the continuation of atazanavir/ritonavir + 2NRTI in virologically suppressed patients, with a sustained benefit in terms of improved renal function and bone mineral density.

Systemic inflammation markers after simplification to atazanavir/ritonavir plus lamivudine in virologically suppressed HIV-1-infected patients: ATLAS-M substudy

Background

Biomarkers of systemic inflammation predict non-AIDS events and overall mortality in virologically suppressed HIV-1-infected patients.

Objectives

To determine whether switching to a dual antiretroviral maintenance therapy was associated with modification of biomarkers of systemic inflammation as compared with continuation of successful standard triple therapy.

Methods

In this substudy of the randomized ATLAS-M trial, we compared in virologically suppressed patients the impact at 1 year of simplification to a dual therapy with atazanavir/ritonavir plus lamivudine versus maintaining atazanavir/ritonavir plus two NRTI triple therapy on markers of systemic inflammation. Plasma levels of interleukin-6, C-reactive protein (CRP), soluble CD14 (sCD14) and D-dimer were quantified by ELISA at baseline and at 48 weeks.

Results

A subset of 139 of 266 randomized patients with available samples was analysed: 69 in the triple therapy arm and 70 in the dual therapy arm. The baseline biomarker levels were comparable between randomization arms. No significant differences in changes from baseline to week 48 were observed between arms (dual therapy versus triple therapy): IL-6, -0.030 versus -0.016 log10 pg/L; CRP, +0.022 versus +0.027 log10 pg/mL; sCD14, -0.016 versus +0.019 log10 pg/mL; and D-dimer, -0.031 versus +0.004 log10 pg/mL. A history of cancer was associated with higher baseline levels of IL-6 (P = 0.002) and CRP (P = 0.049). No relationship was observed between baseline biomarker level and persistent residual viraemia, HIV-1 DNA load, plasma lipids and other potential explanatory variables.

Conclusions

Simplification with atazanavir/ritonavir plus lamivudine does not affect plasma markers of systemic inflammation in virologically suppressed patients. The association between these findings and clinical outcomes requires further evaluation.

Long-term data on the efficacy and tolerability of lamivudine plus dolutegravir as a switch strategy in a multi-centre cohort of HIV-1-infected, virologically suppressed patients

BACKGROUND

Results from clinical trials and observational studies suggest that lamivudine plus dolutegravir (3TC+DTG) could be an effective and tolerated option for simplification in human immunodeficiency virus (HIV)-1-positive patients.

MATERIALS AND METHODS

This observational study enrolled HIV-1-infected, virologically suppressed patients switching to 3TC+DTG. Kaplan-Meyer survival analysis was performed to evaluate time to virological failure (VF; defined by a single HIV-RNA determination ≥1000 copies/mL or by two consecutive HIV-RNA determinations ≥50 copies/mL) and time to treatment discontinuation (TD; defined as interruption of either 3TC or DTG), Cox regression was performed to assess predictors, and linear mixed model was performed for repeated measures to measure changes in immunological and metabolic parameters.

RESULTS

Five hundred and fifty-six patients were eligible for analysis. Their median CD4+ count at baseline was 668 cells/mm³ and median time of virological suppression was 88 months. Estimated probabilities of maintaining virological suppression at 96 and 144 weeks of follow-up were 97.5% [standard deviation (SD) 0.8] and 96.5% (SD 1.0), respectively. Years since HIV diagnosis was the only predictor of VF. In patients with time of virological suppression <88 months, the rate of VF was higher in the presence of the M184V mutation. Estimated probabilities of remaining on 3TC+DTG at 96 and 144 weeks of follow-up were 79.2% (SD 1.9) and 75.2% (SD 2.2), respectively. A significant increase in CD4 cell count (+44 cells/mm³, P=0.015), CD4/CD8 ratio (+0.10, P=0.002) and high-density lipoprotein cholesterol (+5.4 mg/dL, P=0.036) was found at 144 weeks of follow-up; meanwhile, total cholesterol (-9.1 mg/dL, P=0.007) and triglycerides (-2.7, P=0.009) decreased significantly.

CONCLUSIONS

These findings confirm the efficacy and tolerability of 3TC+DTG in virologically suppressed patients.

No Significant Changes to Residual Viremia After Switch to Dolutegravir and Lamivudine in a Randomized Trial

In the ASPIRE trial, antiretroviral therapy (ART) switch to dolutegravir plus lamivudine (DTG+3TC) was comparable to 3-drug ART in maintaining viral suppression by standard viral load assays. We used an ultrasensitive assay to assess whether this switch led to increased residual viremia. At entry, levels of residual viremia did not differ significantly between arms (DTG+3TC vs 3-drug ART: mean, 5.0 vs 4.2 HIV-1 RNA copies/mL; P = .64). After randomization, no significant between-group differences were found at either week 24 or 48. These results show no evidence for increased viral replication on DTG+3TC and support its further investigation as a dual ART strategy.

Systematic De-escalation of Successful Triple Antiretroviral Therapy to Dual Therapy with Dolutegravir plus Emtricitabine or Lamivudine in Swiss HIV-positive Persons

BACKGROUND

Studies increasingly suggest that the efficacy of certain dual antiretroviral therapy (ART) combinations is equal to triple ART. Increasing concerns among HIV-positive patients and physicians in Switzerland include ART cost and long-term ART safety and toxicity, i.e. taking only as many ART agents as necessary. The aims of this retrospective analysis are to report on the de-escalation of our entire clinic population of eligible patients with well-controlled HIV-infection to dolutegravir-containing dual ART.

METHODS

Starting in March 2015, we systematically considered the de-escalation of eligible patients to either dolutegravir/emtricitabine or dolutegravir/lamivudine, by discontinuing tenofovir disoproxil fumarate or abacavir. We report on the virological efficacy, tolerability and patient satisfaction ≥ 48 weeks after de-escalation.

FINDINGS

Of 106 HIV-positive patients followed in our clinic, 70 patients were de-escalated. Three returned to triple ART (insomnia after dolutegravir start, n = 2; new wish for single tablet regimen, n = 1). All de-escalated patients and all who continued triple ART had suppressed HIV viremia at last follow-up and were satisfied with their ART regimen, except for one patient who had virological failure after ART discontinuation in the setting of major depression. The most common reasons to not de-escalate included hepatitis B co-infection (n = 6), physician's concern about ART adherence (n = 6), patient reluctance to switch from a single tablet to a 2-tablet regimen (n = 7), patient satisfied with current ART (n = 5) and others (n = 12).

INTERPRETATION

ART de-escalation to dolutegravir/FTC or dolutegravir/3TC is possible in the majority of patients virologically suppressed on triple ART, and may effectively address patient and physician concerns about long-term safety and cost of ART.

Dual antiretroviral therapy with tenofovir (TDF) and darunavir/ritonavir (DRV/RTV) in an HIV-1 positive patient: a case report, review, and meta-analysis of the literature on dual treatment strategies using protease inhibitors in combination with an NRTI

BACKGROUND

Here, we report the case of an HIV positive patient under a dual antiretroviral drug regimen with tenofovir disoproxil and darunavir/ritonavir with stable clinical, virological, and immunological response over 126 weeks. Dual antiretroviral therapy has the advantage of reduced toxicity and lower health care costs, treatment failure and fostering drug resistance are perceived risks. Optimal drug combinations and indication criteria for dual treatment remain controversial. Nevertheless, first clinical trials indicate non-inferiority for combinations of nucleoside reverse transcriptase inhibitors and protease inhibitors. This case presents the combination of tenofovir disoproxil in combination with a protease inhibitor as a new potential dual treatment regimen.

METHOD

We performed a systematic literature search and meta-analysis of trials comparing dual to triple ART.

RESULTS

Literature review revealed nine studies in which dual therapy with a protease inhibitor and an NRTI was compared to triple therapy. We performed a meta-analysis of six trials that reported a 48-week follow-up. In treatment-naïve patients as well when ART switch was assessed, there was no difference in the treatment success in patients with dual ART versus triple.

CONCLUSION

We conclude that dual therapy with a protease inhibitor and NRTI is safe and effective. The use of tenofovir in dual treatment as described in our case needs to be assessed in future clinical trials.

Biochemical and inflammatory modifications after switching to dual antiretroviral therapy in HIV-infected patients in Italy: a multicenter retrospective cohort study from 2007 to 2015

BACKGROUND

Triple-drug regimens are the gold standard for HIV therapy. Nucleos(t)ide reverse transcriptase inhibitors (NRTIs) reducing regimens are used to decrease drugs toxicity, exposure and costs. Aim of our study was to evaluate trends of biochemical and inflammatory indices in patients switching to dual therapy (DT).

METHODS

We included patients that a) switched to a DT from 2007 to 2015 from a tenofovir/abacavir-based triple regimen b) previously maintained a triple and c) subsequently a dual regimen for 12 months with virological suppression. We retrieved data measured at 5 points (at the switch, 6 and 12 months before and after switch). We used platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR) and CD4/CD8 ratio as inflammatory indices. We assessed temporal trends of viro-immunological, biochemical and inflammatory parameters.

RESULTS

Overall, 364 and 65 patients switched from a tenofovir- and an abacavir-triple regimen, respectively. In the tenofovir-reducing group, creatinine clearance and lipids raised after the switch. There was a significant increase in both CD4+ cells and CD4/CD8. CD8+ cells rose after the switch, while opposite trend was found for PLR. In the abacavir-reducing group total lipids showed a decrease during the first 6 months after the switch and then stabilized. An increase of CD4+ and a decrease of CD8+ cells was observed during the study period, although not statistically significant. While CD4/CD8 remained stable after simplification, PLR decreased significantly after 6 months, then returning to baseline. CD8+ cells increased in the tenofovir-reducing group despite a viro-immunological response. Intriguingly, PLR decreased, maintaining this trend for 12 and 6 months after tenofovir and abacavir interruption respectively.

CONCLUSIONS

Increased PLR has been linked to hypercholesterolemia and metabolic-syndrome, while high CD8+ cells count to increased risk of non-AIDS-related events regardless of CD4 T-cell recovery and to virological failure. Whether these findings may have clinical implications, and which role DT plays on the immune system and on inflammation should be further investigated.

Switching to dual/monotherapy determines an increase in CD8+ in HIV-infected individuals: an observational cohort study

BACKGROUND

The CD4/CD8 ratio has been associated with the risk of AIDS and non-AIDS events. We describe trends in immunological parameters in people who underwent a switch to monotherapy or dual therapy, compared to a control group remaining on triple antiretroviral therapy (ART).

METHODS

We included patients in Icona who started a three-drug combination ART regimen from an ART-naïve status and achieved a viral load ≤ 50 copies/mL; they were subsequently switched to another triple or to a mono or double regimen. Standard linear regression at fixed points in time (12-24 months after the switch) and linear mixed model analysis with random intercepts and slopes were used to compare CD4 and CD8 counts and their ratio over time according to regimen types (triple vs. dual and vs. mono).

RESULTS

A total of 1241 patients were included; 1073 switched to triple regimens, 104 to dual (72 with 1 nucleoside reverse transcriptase inhibitor (NRTI), 32 NRTI-sparing), and 64 to monotherapy. At 12 months after the switch, for the multivariable linear regression the mean change in the log₁₀ CD4/CD8 ratio for patients on dual therapy was -0.03 (95% confidence interval (CI) -0.05, -0.0002), and the mean change in CD8 count was +99 (95% CI +12.1, +186.3), taking those on triple therapy as reference. In contrast, there was no evidence for a difference in CD4 count change. When using all counts, there was evidence for a significant difference in the slope of the ratio and CD8 count between people who were switched to triple (points/year change ratio = +0.056, CD8 = -25.7) and those to dual regimen (ratio = -0.029, CD8 = +110.4).

CONCLUSIONS

We found an increase in CD8 lymphocytes in people who were switched to dual regimens compared to those who were switched to triple. Patients on monotherapy did not show significant differences. The long-term implications of this difference should be ascertained.

Current and emerging two-drug approaches for HIV-1 therapy in ART-naïve and ART-experienced, virologically suppressed patients

INTRODUCTION

Current guidelines recommend a 2-drug antiretroviral regimen as an alternative to triple antiretroviral therapy (ART) in selected patients to reduce long-term toxicity and costs.

AREAS COVERED

This review is intended to provide insight into the efficacy, safety and tolerability of 2-drug versus 3-drug ART in naïve and in treatment-experienced virologically-suppressed patients.

EXPERT OPINION

Dual therapy regimens are not feasible in HBV-coinfected individuals and should not be applied during pregnancy. Positive data on 2-drug ART in drug naïve patients are still limited, while, in virologically-suppressed individuals, several regimens have shown non-inferiority as compared to 3-drug regimens. The strongest evidence of efficacy applies to ritonavir-boosted PI regimens combined with lamivudine and to dolutegravir with rilpivirine. Dual therapies showed improved renal function and bone mineral density over tenofovir disoproxil fumarate-based 3-drug regimens. There are also great expectations for ongoing phase 3 trials testing dolutegravir with lamivudine. New and future single tablet co-formulations of dual regimens are expected to improve their suitability. Despite the lack of comparison with tenofovir alafenamide-based 3-drug regimens, the 2-drug regimens showing consistent non-inferiority and safety versus 3-drug regimens will challenge the current paradigm of 3-drug ART.

HIV-1 non-R5 tropism correlates with a larger size of the cellular viral reservoir and a detectable residual viremia in patients under suppressive ART

BACKGROUND

The influence of HIV-1 co-receptor usage on the course of therapy in subjects fully responding to ART has been poorly investigated.

OBJECTIVES

To explore the relationship between co-receptor tropism and cellular reservoir size, residual viremia and subsequent virological outcome in ART-treated patients with HIV-1 RNA stable <50 copies/mL.

STUDY DESIGN

Viral co-receptor usage was predicted by viral env DNA sequencing with geno2pheno interpretation (FPR20%) and classified as R5 and non-R5. Total blood-associated HIV-1 DNA levels (log₁₀ copies/10⁶ leukocytes) were measured by qRT-PCR (5'LTR). Residual plasma viremia was categorized as detectable (1-49 cps/mL) or undetectable (<1 copy/mL). Virological rebounds (any HIV-1 RNA >50 copies/mL) were evaluated over 96 weeks.

RESULTS

The study included 116 subjects. Patients with R5 virus (n = 59) and non-R5 virus (n = 57) were homogeneous for the main characteristics except for the lower nadir CD4 cell count in the non-R5 group. Patients with non-R5 variants showed higher levels of HIV-1 DNA as compared to patients with R5 virus: mean 2.47 (95% CI 2.37-2.56) vs 2.17 (2.08-2.26) (p < 0.001). Moreover, a higher proportion of patients in the non-R5 group displayed detectable residual viremia with respect to the R5-group (54.4% vs 32.2%, p = .016). Detectable residual viremia was found to be significantly associated with viral rebounds.

CONCLUSION

The presence of non-R5 viral DNA variants is related to a higher probability of residual viremia and to a larger size of the cellular viral reservoir in this setting. These data highlight a potential role of viral tropism in the monitoring of HIV-1 infection in virologically controlled subject.

Dolutegravir plus rilpivirine dual therapy in treating HIV-1 infection

INTRODUCTION

The HIV-infected population is aging and comorbidities and polypharmacological regimens are increasing. To reduce toxicity and drug burden researchers are evaluating the efficacy, safety and durability of dual therapies as a switch option in subjects who have achieved stable virologic suppression. Initially effective dual combinations relied on protease inhibitors but when dolutegravir, the first integrase inhibitor to display a high genetic barrier, became commercially available, many physicians began to use it in a variety of dual regimens, generating several observational cohorts. Areas covered: This review covers the most recent data from observational cohorts and randomized clinical trials concerning the switch to the dual combination of dolutegravir plus rilpivirine and the reasons that lead to consider this option. Also, viral failures, due to poor adherence or to other factors, and drug resistance are investigated. Articles which are searchable on MEDLINE/PubMed and from the main national/international congresses in the field of HIV therapy are reviewed. Expert opinion: The observation period for this regimen is getting longer and data showing its efficacy in maintaining HIV-1 RNA < 50 copies/mL are now consolidated. Metabolic data suggest some benefit in the lipid profile, improvement in bone mineral density and reduced bone reabsorption.

Simplification to dual-therapy containing lamivudine and darunavir/ritonavir or atazanavir/ritonavir in HIV-infected patients on virologically suppressive antiretroviral therapy

BACKGROUND

The ritonavir-boosted protease inhibitor (PI/r)-based dual regimens are warranted in order to optimize the combination antiretroviral therapy (cART), prevent the long-term toxicity and reduce the cost of treatments.

METHODS

We performed an observational, retrospective study of HIV-infected patients on suppressive antiretroviral therapy who switched to a dual regimen containing lamivudine (3TC) plus darunavir/ritonavir (DRV/r) 800/100 mg qd or atazanavir/ritonavir (ATV/r) 300/100 mg qd.

RESULTS

As a whole, 122 well-treated patients (mean age, 45.2 years; mean CD4 T + lymphocyte count, 589 cells/mm³; mean duration of current cART, 3.1 years) were enrolled. Current antiretroviral regimen included tenofovir/emtricitabine in 91 subjects, abacavir/lamivudine in 25, lopinavir/r in 41, DRV/r in 38 and ATV/r in 33. Baseline mean estimated glomerular filtration rate (eGFR) was 94.2 mL/min/1.73 m², and proteinuria was detected in 46 subjects (38%). Overall 70 subjects switched to 3TC + DRV/r (group A) and 52 to 3TC + ATV/r (group B). After 12 months, 65 patients (92.8%) in group A and 46 (88.4%) in group B showed HIV RNA <20 copies/mL. A significant and comparable increase in eGFR was observed in group A and B (+3.8 and +3.1 mL/min/1.73 m², respectively), such as a significant decrease in prevalence of proteinuria. A significantly greater increase in total bilirubin concentration was reported in group B than in group A.

CONCLUSION

In our study, simplification to a dual therapy containing 3TC + DRV/r or ATV/r in virologically suppressed patients was effective and showed a good tolerability profile.

Pharmacokinetic drug evaluation of dolutegravir plus rilpivirine for the treatment of HIV

INTRODUCTION

The search for simple, potent, metabolic-friendly and nucleoside/nucleotide sparing antiretroviral regimens has led clinical investigators to move steps towards dual therapies. Among these the association of rilpivirine and dolutegravir is emerging as a twin randomized clinical trial (SWORD1&2) and at least three observational cohort describe it as a safe and highly effective regimen for switch from other therapies Areas covered: We review the evidence supporting the use of dolutegravir plus rilpivirine for the treatment of HIV in virologically suppressed patients taking other antiretroviral regimens. The reasons for the switch in clinical practice may range from simplification to tolerability/toxicity issues, to the prevention of future metabolic damage, to predicted drug-drug interactions when treatment of HCV co-infection is planned. Articles searchable on MEDLINE/PubMed and from the main international congresses in the field of HIV therapy were reviewed to provide context for use of dolutegravir plus rilpivirine Expert opinion: This treatment is highly effective in maintaining HIV-1 RNA <50 copies/mL. Although the studies up to date requested patient to switch to drugs they had no experience of, a predictable 'radical change' effect did not impact negatively on the results. Further data from these studies may help elucidate the possible advantage in terms of safety and metabolic effect in the next few months.