Switching tenofovir/emtricitabine plus lopinavir/r to raltegravir plus Darunavir/r in patients with suppressed viral load did not result in improvement of renal function but could sustain viral suppression: a randomized multicenter trial

Rilpivirine plus cobicistat-boosted darunavir as a two-drug switch regimen in HIV-infected, virologically suppressed subjects on steady standard three-drug therapy: a randomized, controlled, non-inferiority trial (PROBE 2)

BACKGROUND

We explored the combination of rilpivirine plus cobicistat-boosted darunavir [a two-drug regimen (2DR)] when switching from standard triple combined ART.

METHODS

In this randomized, open-label, non-inferiority trial, participants had an HIV-RNA <50 copies/mL on a stable (>6 months) three-drug regimen. The primary endpoint was proportion with HIV-RNA <50 copies/mL at Week 24 (snapshot algorithm), with a -12% non-inferiority margin. ClinicalTrials.gov: NCT04064632.

RESULTS

One hundred and sixty patients were allocated (1:1) to 2DR or to continue current ART (CAR). At Week 24, 72 (90.0%) of participants with 2DR and 75 (93.8%) with CAR maintained HIV-RNA <50 copies/mL [difference -3.75% (95% CI = -11.63 to 5.63)], confirming non-inferiority. Non-inferiority was confirmed considering an HIV-RNA >50 copies/mL (0% for 2DR; 3.7% for CAR; 95% CI = -0.4 to 7.9). Four patients reported adverse events not leading to treatment discontinuation (one patient in the 2DR group and three patients in the CAR group); eight subjects discontinued therapy in the 2DR group and three in the CAR group. With 2DR, lipid serum concentrations increased, but differences were statistically significant only for tenofovir disoproxil fumarate-containing CAR and in 2DR patients receiving a pre-switch regimen including tenofovir disoproxil fumarate. Median bone stiffness decreased in the CAR group from 86.1 g/cm2 (IQR = 74-98) to 83.2 g/cm2 (IQR = 74-97) and increased in the 2DR group from 84.9 g/cm2 (IQR = 74-103) to 85.5 g/cm2 (IQR = 74-101). The reduction within the CAR group was significant (P = 0.043).

CONCLUSIONS

Once-daily rilpivirine plus cobicistat-boosted darunavir is an effective 2DR that combines a high virological efficacy with a potential to avoid major NRTI toxicities.

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.

Nucleos(t)ide reverse transcriptase inhibitor-sparing regimens in the era of standard 3-drug combination therapies for HIV-1 infection

Nucleos(t)ide reverse transcriptase inhibitor (NRTI)-sparing regimens have often been selected as antiretroviral therapy (ART) for HIV-1 infection recently, but data for characteristics have been lacking. This study aimed to document the current status of NRTI-sparing regimens in the era of standard 3-drug combination therapies. We cross-sectionally compared characteristics of patients treated with NRTI-sparing regimens (NRTI-sparing group) with dolutegravir plus tenofovir alafenamide fumarate/emtricitabine as a standard ART group in 2018. The NRTI-sparing and the standard ART groups included 61 and 469 patients, respectively. The mean (± standard deviation) age and serum creatinine of the NRTI-sparing group were significantly higher than those of the standard ART group (57.6 ± 12.8 years vs 42.8 ± 10.4 years (p < 0.05) and 2.09 ± 3.10 mg/dL vs. 0.93 ± 0.19 mg/dL (p < 0.05), respectively. The percentage of patients with NRTI-sparing regimens increased with age; with less than 5% in their 50s or younger, 8.4% in their 60s, and 14.1% aged ≥ 70 years. The primary reason for switching to the NRTI-sparing regimen was due to reduced renal function. According to the limited data, viral suppression was achieved at week 48 in all patients in the NRTI-sparing group. No patient had treatment failure nor developed drug resistance. The use of NRTI-sparing regimens increased with age. They were more frequently used in patients aged ≥ 60 years and those with decreased renal function.

Dual therapy with raltegravir plus a fixed dose combination of darunavir/ritonavir in people living with HIV in Argentina

Objective

There are generic fixed-dose combinations (FDCs) of ritonavir-boosted darunavir (DRV/r) available in Argentina. Experiences with these FDCs in dual therapy remain limited in clinical practice. We aimed to describe clinical and virologic outcomes in patients exposed to FDC DRV/r + raltegravir (RAL) 400 mg every 12 h in a real-life setting.

Patients and methods

. Retrospective analysis of electronic medical records of HIV-infected patients under FDC DRV/r + RAL in an HIV clinic in Argentina (2014-2018). Individuals were classified as “switch group” (SG, undetectable viral load [VL] with any toxicity/comorbidity) and “virologic group• (VG, detectable viremia and infection by multidrug-resistant HIV).

Results

Of 7,380 patients on ART, 116 (1.5%) received FDC DRV/r + RAL, being 58% in SG. Sixty percent received DRV/r 800/100 mg dose (rest, 600/100 mg). The median (IQR) age and CD4+ T-cell count were: 52 (42-58) years, and 373 cell/µL (202-642). Ninety-eight percent were ART-experienced with a median of 3 (IQR 2-5) prior treatments. Main reasons for switch (SG) were renal (57%), cardiovascular (54%) and bone (14%) comorbidities. Median exposure to DRV/r + RAL was 18 months. Among patients in SG, 98% and 96% had undetectable VL at 6 and 12 months; in the VG, 89% and 87% had undetectable VL at 6 and 12 months. No patient required suspension due to toxicity/ intolerance.

Conclusion

In this cohort of mostly experienced HIV-infected patients, FDC DRV/r + RAL was effective and safe. Such therapy may be considered an option for patients with comorbid conditions and/or with multidrug-resistant HIV.

Switching from tenofovir disoproxil fumarate to tenofovir alafenamide or dual therapy-based regimens in HIV-infected individuals with viral load ≤50 copies/mL: does estimated glomerular filtration rate matter?

Our aim was to evaluate the association between recent eGFR values and risk of switching from TDF to TAF or dual therapy (DT) in real life. HIV-positive patients achieving HIV-RNA ≤50 copies/mL for the first time after starting a TDF-based regimen were included. Kaplan-Meier (KM) curves and Cox regression models were used to estimate the time from TDF to switch to TAF or DT. 1486 participants were included: median (IQR) age 36 (30-42) years; baseline CKD-EPI eGFR 99.92 (86.47-111.4) mL/min/1.73m². We observed a consistently higher proportion of people with HIV-RNA ≤50 copies/mL who switched from TDF to TAF rather than to DT. By competing risk analysis, at 2 years from baseline, the probability of switching was 3.5% (95% CI 2.6-4.7%) to DT and 46.7% (42.8-48.5%) to TAF. A significantly higher probability of switching to TAF was found for patients receiving INSTI at baseline versus NNRTIs and PI/b [KM, 65.6% (61.7-69.4%) vs. 4.0% (1.8-6.1%) and 59.9% (52.7-67.2%), respectively; P < 0.0001]. eGFR <60 mL/min/1.73m² both as time-fixed covariate at baseline or as current value was associated with a higher risk of switching to DT [aHR 6.68 (2.69-16.60) and 8.18 (3.54-18.90); P < 0.001] but not to TAF-based cART [aHR 0.94 (0.39-2.31), P = 0.897; and 1.19 (0.60-2.38), P = 0.617]. Counter to our original hypothesis, current eGFR is used by clinicians to guide switches to DT but does not appear to be a key determinant for switching to TAF.

Efficacy and Safety of Switching to Dolutegravir With Boosted Darunavir in Virologically Suppressed Adults With HIV-1: A Randomized, Open-Label, Multicenter, Phase 3, Noninferiority Trial: The DUALIS Study

Background

Dolutegravir (DTG) and boosted darunavir (bDRV) are potent antiretrovirals with a high resistance barrier and might be valuable switch options for people with HIV (PWH).

Methods

DUALIS, a randomized, open-label, phase 3b, noninferiority clinical trial, compared the switch to DTG + bDRV (2DR) with continuation of 2 nucleoside reverse transcriptase inhibitors (2NRTI) + bDRV (3DR). PWH with HIV RNA <50 copies/mL taking 2NRTI + bDRV (3DR) for ≥24 weeks (1 accepted blip <200 copies/mL) were randomized to either switch to DTG 50 mg + DRV 800 mg (boosted with 100 mg of ritonavir) or continue taking 3DR. The primary end point (PE) was the proportion of HIV RNA <50 copies/mL at week (W) 48. Change in NRTI backbone was not classified as failure. The estimated sample size for PE analysis was 292; the noninferiority margin was ≤-10.0%.

Results

In total, 263 subjects were randomized and treated (2DR n = 131, 3DR n = 132; 90.1% male; 89.7% Caucasian; median age [interquartile range], 48 [39-54] years). At W48, 86.3% (n = 113/131) of the 2DR subject and 87.9% (n = 116/132) of the 3DR subjects had HIV RNA <50 copies/mL; the difference between arms was -1.6% (95.48% CI, based on the adjusted alpha level accounting for the interim analysis at W24, -9.9% to +6.7%; discontinuations due to adverse events: 2DR, 4.6% [n = 6]; 3DR, 0.8% [n = 1]). Kaplan-Meier estimates of confirmed HIV RNA ≥50 copies/mL at W48 were 1.6% (n = 2) in the 2DR and 3.1% (n = 4) in the 3DR group. Development of treatment-emergent resistance was not observed.

Conclusions

Switching to DTG + bDRV was noninferior to continuing 3DR in subjects already treated with bDRV.

Optimizing Antiretroviral Therapy in Treatment-Experienced Patients Living with HIV: A Critical Review of Switch and Simplification Strategies. An Opinion of the HIV Practice and Research Network of the American College of Clinical Pharmacy

Simplifying or switching antiretroviral therapy (ART) in treatment-experienced people living with HIV (PLWH) may improve adherence, tolerability, toxicities, and/or drug–drug interactions. The purpose of this review is to critically evaluate the literature for efficacy and safety associated with switching or simplifying ART in treatment-experienced PLWH. A systematic literature search using MEDLINE was performed from January 1, 2010 to April 30, 2018. References within articles of interest, the Department of Health and Human Services guidelines, and conference abstracts were also reviewed. Switch/simplification strategies were categorized as those supported by high-level clinical evidence and those with emerging data. Rates of virologic suppression were noninferior for several switch/simplification strategies when compared to baseline ART. Potential for reducing adverse events was also seen. Additional evidence for some strategies, including most 2-drug regimens, is needed before they can be recommended.

Efficacy and safety of dolutegravir plus boosted-darunavir dual therapy among highly treatment-experienced patients

BACKGROUND

Dual therapies decrease toxicity, pill-burden and treatment-associated cost. The combination of high genetic barrier drugs such as dolutegravir plus boosted-darunavir may be suitable as simplification regimen for patients harbouring multidrug-resistant virus.

METHODS

Patients switched to a once-daily regimen consisting of dolutegravir plus darunavir, boosted with cobicistat or ritonavir, were included in this cohort study. The primary end point was the proportion of patients with HIV RNA viral load <37 copies/ml at week 48 (NCT02491242).

RESULTS

Overall, 51 patients were enrolled. At baseline, all patients had failed to ≥2 antiretroviral classes. Genotypic resistance profiles showed a mean of primary mutations of 1.2 for non-nucleoside reverse transcriptase inhibitors, 2.4 for nucleoside/nucleotide reverse transcriptase inhibitors and 3.5 for protease inhibitors (PIs), but they were virologically suppressed for a median of 33 months (IQR 12-60). Only five patients had reduced sensitivity to darunavir and mean genotypic susceptibility score of dual therapy was 1.95 over 2. At week 48, there were no virological failures, three patients discontinued the regimen due to neuropsychiatric adverse events, two were lost to follow-up, and therefore the efficacy was 90% (95% CI, 82, 99%, intention-to-treat analysis). Mean estimated glomerular filtration rate decreased by 8.8 ml/min/1.73 m², though kidney tubular parameters, high density lipoprotein-cholesterol and triglycerides levels improved after switching to dual therapy.

CONCLUSIONS

In highly treatment-experienced patients who were virologically suppressed, switching to the combination of dolutegravir plus boosted-darunavir dual therapy was effective and well tolerated, improving lipid and renal parameters.

Two-drug antiretroviral regimens: an assessment of virologic response and durability among treatment-experienced persons living with HIV in the OPERA® Observational Database

INTRODUCTION

Two-drug regimens (2-DR) have the potential to be a viable solution to the challenges of treatment complexity, cost, adverse effects and contraindications. We sought to describe the real-world use and effectiveness of 2-DR among persons living with HIV (PLHIV) in the United States.

METHODS

We analysed data for 10,190 treatment-experienced patients from the OPERA® Observational Database initiating a new 2-DR or three-drug regimen (3-DR) between 1 January 2010 and 30 June 2016. Multivariate Cox Proportional Hazards models were used to estimate the association among 2-DR or 3-DR initiation and virologic suppression (viral load (VL) <50 copies/mL), virologic failure (2 VLs > 200 copies/mL or 1 VL > 200 copies/mL + discontinuation) or regimen discontinuation.

RESULTS

Patients initiating a 2-DR (n = 1337, 13%) were older, and more likely to have a lower CD4 count, a history of AIDS and comorbid conditions than patients initiating a 3-DR. There was no difference between groups in time to virologic suppression (aHR: 1.00 (95% CI: 0.88, 1.13)) among viraemic patients (baseline VL ≥ 50 copies/mL, n = 4180), or time to virologic failure (aHR: 1.15 (95% CI: 0.90, 1.48)) among virologically stable patients (baseline VL < 50 copies/mL, n = 6010). However, time to discontinuation was shorter following 2-DR than 3-DR initiation (aHR: 1.51 (95% CI: 1.41, 1.61)).

CONCLUSIONS

In this large cohort of treatment-experienced patients, 2-DR prescriptions were common and more frequent among patients with significant comorbidity. Virologic response was similar, but duration of use was shorter with a 2-DR than a 3-DR, suggesting that 2-DRs may be a virologically effective treatment strategy for treatment-experienced PLHIV with existing comorbidities.

Uptake and effectiveness of two-drug compared with three-drug antiretroviral regimens among HIV-positive individuals in Europe

OBJECTIVE

To assess the use of two-drug antiretroviral regimens (2DR) and virologic and immunologic outcomes compared with three-drug regimens (3DR) in the EuroSIDA cohort.

DESIGN

Multicentre, prospective cohort study.

METHODS

Logistic regression was used to analyse the uptake and outcomes among HIV-positive individuals who started or switched to a 2DR compared with those on a 3DR. Virologic outcomes were assessed on-treatment as the proportion of individuals with controlled viral load (<400 copies/ml), or with a composite modified FDA snapshot endpoint (mFDA), with mFDA success defined as controlled viral load at 6 months or 12 months for individuals with a known viral load, no regimen changes, AIDS or death. Immunologic response was defined as a 100 cells/μl or a 25% increase in CD4 cell counts from baseline.

RESULTS

Between 1 July 2010 and 31 December 2016, 423 individuals started or switched to a 2DR (eight antiretroviral-naive) and 4347 started a 3DR (566 naive). Individuals on 2DR tended to have suppressed viral load, higher CD4 cell counts and more comorbidities at baseline compared with those on 3DR. There were no differences in the proportions of individuals who obtained on-treatment or mFDA success, and no significant differences in the adjusted odds ratios for mFDA success or immunologic responses between the 2DR and 3DR groups at 6 months or 12 months.

CONCLUSION

In routine clinical practice, 2DR were largely used for virologically suppressed individuals with higher cumulative exposure to antiretrovirals and comorbidities. Virologic and immunologic outcomes were similar among those on 2DR or 3DR, although confounding by indication cannot be fully excluded due to the observational nature of the study.

Two-drug regimens for treatment of naïve HIV-1 infection and as maintenance therapy

As people live longer with HIV infection, there has been a resurgence of interest in challenging the use of three-drug therapy, including two nucleoside reverse transcriptase inhibitors plus a third drug, as initial treatment of HIV infection or for maintenance therapy in virologically suppressed individuals. Although initial studies showed poor efficacy and/or substantial toxicity, more recent regimens have held greater promise. The SWORD-1 and -2 studies were pivotal trials of dolutegravir plus rilpivirine as maintenance therapy in virologically suppressed patients with no history of drug resistance, leading to the US Food and Drug Administration’s approval of the regimen as a small, single tablet. More recently, the GEMINI-1 and -2 studies demonstrated that dolutegravir plus lamivudine is as safe and effective as the same regimen when combined with tenofovir disoproxil fumarate in treatment-naïve individuals. Together, these and other studies of novel two-drug regimens offer the potential for improved tolerability and simplicity, as well as a reduction in cost. We will review historical and recent trials of two-drug therapy for the treatment of HIV-1 infection.

Switching to abacavir versus use of a nucleoside-sparing dual regimen for HIV-infected patients with tenofovir-associated renal toxicity

OBJECTIVES

We investigated the reversibility of tenofovir disoproxil fumarate (TDF)-associated renal decline and tubular dysfunction using different antiretroviral strategies.

METHODS

A successive evaluation of renal [estimated glomerular filtration rate (eGFR)] and tubular (phosphataemia, proteinuria, albuminuria, phosphaturia, uricosuria, glycosuria and tubular proteinuria) parameters was performed in 231 patients, before and after switching from TDF to abacavir (n = 60), using dual therapy (n = 49), or continuing the same regimen including TDF (n = 122).

RESULTS

In a successive evaluation after a median of 8.86 months, or less time if treatment was switched (4.8 months vs. 13.3 months to second evaluation; P < 0.01), a significant improvement in eGFR (median change +0.3 vs. -2.91 mL/min/1.73 m2 in patients who did not discontinue TDF; P = 0.04) and tubular dysfunction (median change -40% vs. +30%, respectively; P < 0.01) was observed. Lineal regression showed that age (β = -0.14; P = 0.04), previous eGFR decline (β = -0.42; P < 0.01), and time on TDF (β = -0.19; P = 0.04) were associated with impaired eGFR recovery. There were no differences in eGFR slopes between patients using abacavir instead of TDF and those using a dual therapy, who showed similar improvement in proteinuria (-22% vs. -19%, respectively), phosphaturia (+10.1% vs. +9.4%, respectively), and urinary beta-2-microglobulin (-9% vs. -15%, respectively; P > 0.1 for all), although patients receiving the dual regimen were more heavily pretreated. A eGFR decrease (-6.17 mL/min/1.73 m2 ) was observed in patients taking dolutegravir or rilpivirine, but with similar improvement to that observed in the rest of switching patients in tubular abnormalities.

CONCLUSIONS

Tenofovir disoproxil fumarate discontinuation was associated with a rapid and significant improvement in eGFR and tubular abnormalities, regardless of whether abacavir or dual therapy was chosen. Switching to a regimen that included dolutegravir and/or rilpivirine was associated with a eGFR decrease without differences in the rate of tubular dysfunction improvement in comparison with the rest of patients who discontinued tenofovir.

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.

Efficacy and safety of boosted darunavir-based antiretroviral therapy in HIV-1-positive patients: results from a meta-analysis of clinical trials

Darunavir/ritonavir (DRV/r) is a second-generation protease inhibitor used in treatment-naïve and -experienced HIV-positive adult patients. To evaluate efficacy and safety in these patient settings, we performed a meta-analysis of randomized controlled trials. We considered eight studies involving 4240 antiretroviral treatment (ART)-naïve patients and 14 studies involving 2684 ART-experienced patients. Regarding efficacy in the ART-naive patients, the virological response rate was not significantly different between DRV/r and the comparator. For the ART-experienced failing patients, the virological response rate was significantly higher with DRV/r than with the comparator (RR 1.45, 95% CI: 1.01-2.08); conversely, no significant differences were found between the treatment-experienced and virologically controlled DRV/r and comparator groups. Regarding safety, the discontinuation rates due to adverse events (AEs) and DRV/r-related serious adverse events (SAEs) did not significantly differ from the rates in the comparator group (RR 0.84, 95% CI: 0.59-1.19 and RR 0.78, 95% CI: 0.57-1.05, respectively). Our meta-analysis indicated that DRV/r-based regimens were effective and tolerable for both types of patients, which was consistent with published data.

Efficacy and safety of nucleoside-sparing regimen based on raltegravir and ritonavir-boosted darunavir in HIV-1-infected treatment-experienced patients

AIM

To assess the efficacy and tolerability of dual therapy containing raltegravir (RAL) and ritonavir boosted darunavir (DRV/r) in HIV-1-infected treatment-experienced patients.

METHOD

Retrospective analysis of 81 HIV-1-infected treatment-experienced patients (56 male and 25 female, 5 Polish centers) who switched to RAL/DRV/r.

RESULTS

The main reasons for the introduction of dual therapy were renal dysfunction (16/81 patients-19.8%) and virologic failure on previous regimens (15/81 patients-18.5%). At 48 weeks the treatment was continued in 58/81 (71.6% of patients). In three patients the therapy was discontinued because of virologic failure. However, no mutations to DRV or integrase inhibitors (InI) were detected. At 48 weeks of treatment CD4⁺ lymphocyte count increased statistically significantly (median 121 cells/μL) P < 0.005. The main reasons for the discontinuation of therapy were treatment simplification (11/23-47.8% patients), adverse events (7/23 patients 30.4%), virologic failure (3/23 patients 13.0%). All patients who switched to RAL/DRV/r therapy because of prior renal impairment were maintained on the treatment for 48 weeks. In this group, before the introduction of dual therapy eGFR (estimated glomerular filtration rate) <60 mL/min/1.72 m² was reported in nine patients and after 48 weeks in four patients (56.3% vs 25%) (P > 0.05). We found a statistically significant decrease in the prevalence of proteinuria or eGFR <60 mL/min/1.72 m² (93.8% vs 37.5%; P = 0.004 before and after the introduction of dual therapy, respectively).

CONCLUSIONS

Dual therapy was effective and safe for the vast majority of antiretroviral-experienced subjects. Such therapy can be recommended especially for patients with renal impairment or NRTIs intolerance.

Dual antiretroviral therapy for HIV infection

INTRODUCTION

For two decades, triple combinations of antiretrovirals have been the standard treatment for HIV infection. The challenges of such lifelong therapy include long-term side effects, high costs and reduced drug adherence. The recent advent of more potent and safer antiretrovirals has renewed the interest for simpler HIV regimens. Areas covered: We discuss the pros and cons of dual antiretroviral therapies in both drug-naïve and in treatment-experienced patients with viral suppression (switch strategy). Expert opinion: Some dual antiretroviral regimens are safe and efficacious, particularly as maintenance therapy. At this time, combinations of dolutegravir plus rilpivirine represent the best dual regimen. Longer follow-up and larger study populations are needed before supporting dolutegravir plus lamivudine. In contrast, dual therapy based on maraviroc is less effective. Although dual regimens with boosted protease inhibitors plus either lamivudine or raltegravir may be effective, they are penalized by metabolic side effects and risk for drug interactions. The newest dual regimens could save money, reduce toxicity and spare drug options for the future. For the first time in HIV therapeutics, less can be more. Dual therapy switching has set up a new paradigm in HIV treatment that uses induction-maintenance.

Lamivudine/dolutegravir dual therapy in HIV-infected, virologically suppressed patients

BACKGROUND

Little is known about the applicability of dual treatments based on integrase inhibitors. We explored the combination of lamivudine + dolutegravir as an option when switching from standard cART in virologically suppressed patients.

METHODS

In this prospective cohort we enrolled patients previously switched to 3TC + DTG who were 18 years or older, with no previous resistance mutations to the used drugs, having a HIV-RNA <50 copies/ml for 6 months or longer, negative for HBsAg and on a stable (>6 months) cART.

RESULTS

Ninety-four individuals were included. They were mostly men (77.7%) with a mean age of 53 years. They presented 159 co-morbidities including cardiovascular, bone, hepatic, kidney, and CNS diseases. Because of these pathologies, they took 207 non-ARV drugs (mean 2.2 per patient). Median duration of viral suppression was 77.5 months (IQR 61). All subjects were prospectively followed up to week 24 and all remained on dual therapy during the whole period. Neither virological failure, nor viral blip was detected. The median CD4 count rose from 658 cells/mcl (IQR 403) to 724 cells/mcl (IQR 401) (P = 0.006) without a significant (P = 0.44) change in the CD4/CD8 ratio. A significant (P < 0.0001) increment of median creatinine from 0.87 mg/dl (IQR 0.34) to 0.95 mg/dl (IQR 0.29) was observed in the first 2 months but thereafter leveled on these values (1.00 mg/dl; IQR 0.35) (P = 0.111 compared to 2 months). The lipid profile slightly improved. The daily cost of cART was significantly (P < 0.0001) reduced of 6.89 euros (SD 6.10).

DISCUSSION

Switching to a dual cART regimen based on lamivudine + dolutegravir maintains virological efficacy up to week 24, and is associated to slight improvements of the immunologic and metabolic status. The strategy allows to freely using concomitant medications for associated pathologies. The dual therapy is less expensive in economic terms.

CONCLUSION

Although still limited evidence exists, a dolutegravir-based dual therapy in combination with lamivudine shows promising results to be confirmed in larger controlled trials.

Comparative effectiveness of tenofovir in HIV-infected treatment-experienced patients: systematic review and meta-analysis

BACKGROUND

Antiretroviral therapy (ART) regimens for HIV infection are frequently changed. We conducted a systematic review of randomized trials (RCTs) on the benefits and harms of switching to tenofovir disoproxil fumarate (TDF)-based regimens in ART-experienced patients.

METHODS

We included RCTs in HIV-infected adults comparing switching to a TDF-containing regimen with maintaining or switching to another regimen. We searched MEDLINE, EMBASE, CENTRAL, LILACS, SCI, and the WHO Global Health Library. We assessed bias with the Cochrane tool and synthesized data using random-effects meta-analyses and Peto's approach. For further analyses, we added data from a previous systematic review in treatment-naïve patients.

RESULTS

17 RCTs with 2210 patients were included. All but one study had a high risk of bias. There was no significant association of switching to TDF-based regimens with mortality, fractures, CD4-cell count, body fat, virological failure, LDL-, and HDL-cholesterol. TDF-based regimens decreased total cholesterol (mean difference -12.05 mg/dL; 95% CI -20.76 to -3.34), trigylcerides (-14.33 mg/dL; -23.73 to -4.93), and bone mineral density (BMD; hip: -2.46%; -3.9 to -1.03; lumbar spine -1.52%; -2.69 to -0.34). Effects on estimated glomerular filtration (eGFR) were inconsistent and depended on the measurement. Adding 22 RCTs from 8297 treatment-naïve patients gave consistent results with then significant reductions of LDL (-7.57 mg/dL; -10.37 to -4.78), HDL (-2.38 mg/dL; -3.83 to -0.93), and eGFR (-3.49 ml/min; -5.56 to -1.43).

CONCLUSIONS

Switching to TDF-based regimens is associated with reductions of BMD and lipid levels and possibly lowered kidney function. The evidence is limited by the high risk of bias.

Modifying Antiretroviral Therapy in Virologically Suppressed HIV-1-Infected Patients

HIV-1-infected patients with suppressed plasma viral loads often require changes to their antiretroviral (ARV) therapy to manage drug toxicity and intolerance, to improve adherence, and to avoid drug interactions. In patients who have never experienced virologic failure while receiving ARV therapy and who have no evidence of drug resistance, switching to any of the acceptable US Department of Health and Human Services first-line therapies is expected to maintain virologic suppression. However, in virologically suppressed patients with a history of virologic failure or drug resistance, it can be more challenging to change therapy while still maintaining virologic suppression. In these patients, it may be difficult to know whether the discontinuation of one of the ARVs in a suppressive regimen constitutes the removal of a key regimen component that will not be adequately supplanted by one or more substituted ARVs. In this article, we review many of the clinical scenarios requiring ARV therapy modification in patients with stable virologic suppression and outline the strategies for modifying therapy while maintaining long-term virologic suppression.

Less-drug regimen including atazanavir in maintenance treatment of HIV infection: how, who, when, why?

For many patients living with HIV-1, the efficacy of combined ART (cART) has made the infection turn to a chronic disease. Because cART is associated with a risk of long-term toxicity, switching patients with virological success to another therapy remains a major issue. Studies undertaken and published over recent years have shown that switching patients exhibiting virological suppression to less-drug regimens (LDR) is a possible option of maintenance strategy. The use of ritonavir-boosted PIs (PI/r) as the backbone of LDR-based maintenance therapy is consistent with their virological potency and a high genetic barrier of resistance. Atazanavir is the most documented PI/r regarding maintenance in dual therapy, with favourable results in terms of virological suppression, tolerance improvement and absence of emergence of mutations. Furthermore, atazanavir is the only commonly prescribed PI that can be used after withdrawal of ritonavir, with maintenance of virological suppression whatever the backbone of associated NRTIs. Based on clinical studies, and taking into account the characteristics of the patients included, one may consider that for any patient with a virological suppression on cART for at least 12 months, with the nadir CD4 >100 cells/mm³ and an absence of encephalitis, an LDR-based maintenance therapy including atazanavir can be considered. Cumulative genotypes must be available to make sure that the LDR will not jeopardize future therapeutic options. The final decision regarding the most appropriate LDR must be guided by the objectives shared by the physician and his/her patient.

NRTI Sparing Therapy in Virologically Controlled HIV-1 Infected Subjects: Results of a Controlled, Randomized Trial (Probe)

Dual treatments could help clinicians to avoid drawbacks and toxicities due to the nucleosidic backbone, while maintaining the efficacy and convenience of robust combination antiretroviral therapy (cART). We explored the combination of rilpivirine plus boosted darunavir (DRV) as an option when switching from standard cART in patients who are virologically suppressed. In this randomized, open-label, proof-of-concept, noninferiority trial, we recruited patients aged 18 years or older with chronic HIV-1 infection and on a stable, effective (>6 months) protease inhibitor-based cART including a nucleosidic backbone. The primary endpoint was noninferiority of the virological response between treatment groups, according to FDA snapshot approach. Sixty patients were randomly allocated to dual treatment with rilpivirine plus boosted DRV or to continue their ongoing triple treatment. Noninferiority was shown at the prespecified level of -12% both at 24 and 48 weeks. At week 24, 100% of patients in the dual arm presented a blood HIV-RNA level <50 copies per milliliter compared with 90.1% in the triple drug arm (difference 9.9%, 95% CI: -0.7 to 20.7), whereas, at 48 weeks, the same proportions were 96.7% and 93.4%, respectively (difference 3.3%, 95% CI: -7.15 to 13.5). The mean change in CD4 cell count from baseline was 6.0 cells per microliter (SD, 184) for dual treatment and 16.5 cells per microliter (SD, 142) for triple treatment. A relevant decrement in CD838HLADR cells was observed in both arms. The reduction was, however, significantly more pronounced in the dual-therapy arm. At week 48, the CD838HLADR cell count was 3.4% (SD, 2.2) in the dual-therapy arm and 5.2% (SD, 3.1) in the triple arm (P = 0.018). None of the patients developed severe adverse events nor had to stop treatment because of adverse events or presented grade 3-4 laboratory abnormalities. A greater reduction of bone stiffness (-2.25; SD, 7.1) was observed in patients randomized to continue triple therapy compared with patients switched to dual therapy (-0.32; SD, 8.8). Finally, baseline HIV-DNA content directly correlated with pre-cART viral load of patients (P = 0.021), but not with time on cART or time with HIV-RNA below 50 copies per milliliter. Independently of the study arm, patients with a n HIV-RNA level constantly above 3 copies per milliliter or showing viral blips had baseline HIV-DNA levels significantly higher (64,656 copies per 10 cells; SD, 93057) compared with patients who constantly presented a HIV-RNA level below the detection limit of 3 copies per milliliter (14,457 copies per 10 cells; SD, 14098) (P = 0.001). A rilpivirine-boosted plus ritonavir-boosted DRV therapy was not inferior over 48 weeks to a standard boosted protease inhibitor-based triple cART. The dual therapy did not negatively affect lipid profile and renal function and was more friendly on bone metabolism. This approach constitutes an alternative for patients experiencing nucleoside reverse transcriptase inhibitor-related toxicities.

Dual Therapy Treatment Strategies for the Management of Patients Infected with HIV: A Systematic Review of Current Evidence in ARV-Naive or ARV-Experienced, Virologically Suppressed Patients

Objective

We reviewed the current literature regarding antiretroviral (ARV)-sparing therapy strategies to determine whether these novel regimens can be considered appropriate alternatives to standard regimens for the initial treatment of ARV-naive patients or as switch therapy for those patients with virologically suppressed HIV infection.

Methods

A search for studies related to HIV dual therapy published from January 2000 through April 2014 was performed using Biosis, Derwent Drug File, Embase, International Pharmaceutical Abstracts, Medline, Pascal, SciSearch, and TOXNET databases; seven major trial registries, and the abstracts of major conferences. Using predetermined criteria for inclusion, an expert review committee critically reviewed and qualitatively evaluated all identified trials for efficacy and safety results and potential limitations.

Results

Sixteen studies of dual therapy regimens were critiqued for the ARV-naive population. Studies of a protease inhibitor/ritonavir in combination with the integrase inhibitor raltegravir or the nucleoside reverse transcriptase inhibitor lamivudine provided the most definitive evidence supporting a role for dual therapy. In particular, lopinavir/ritonavir or darunavir/ritonavir combined with raltegravir and lopinavir/ritonavir combined with lamivudine demonstrated noninferiority to standard of care triple therapy after 48 weeks of treatment. Thirteen trials were critiqued in ARV-experienced, virologically suppressed patients. The virologic efficacy outcomes were mixed. Although overall data regarding toxicity are limited, when compared with standard triple therapy, certain dual therapy regimens may offer advantages in renal function, bone mineral density, and limb fat changes; however, some dual combinations may elevate lipid or bilirubin levels.

Conclusions

The potential benefits of dual therapy regimens include reduced toxicity, improved tolerability and adherence, and reduced cost. Although the data reviewed here provide valuable insights into the effectiveness and tolerability of dual therapy regimens, it remains unclear whether these potential benefits can be maintained long-term. Appropriately powered studies with longer follow-up periods are needed to more definitively assess potential toxicity reduction advantages with dual therapy.

Improvement in renal function and bone mineral density after a switch from tenofovir/emtricitabine plus ritonavir-boosted protease inhibitor to raltegravir plus nevirapine: a pilot study

BACKGROUND

The antiretroviral regimens including tenofovir and a ritonavir-boosted protease inhibitor (r/PI) have been associated with a reduced bone mineral density (BMD), increased bone turnover markers and renal tubular dysfunction.

METHODS

An observational, prospective study was performed including HIV-1-infected, virologically suppressed patients treated with tenofovir/emtricitabine plus an r/PI for at least 12 months who switched to raltegravir plus nevirapine. The primary end point was changes after 48 weeks in estimated glomerular filtration rate (eGFR), prevalence of tubular dysfunction, BMD and concentration of two serum markers of bone turnover: collagen type-1 cross-linked C-telopeptide (CTX) and bone-specific alkaline phosphatase (BAP).

RESULTS

A total of 46 patients were enrolled: 78% were male, 96% were Caucasian, the mean age was 45 years and the mean CD4(+) T-lymphocyte count was 681 cells/mm(3). A renal impairment was present in 72% of patients and was the main reason for the switch. After 48 weeks, prevalence of proximal tubular dysfunction decreased significantly (-72%; P<0.001), whereas the mean value of eGFR did not change significantly. At the same time, after 48 weeks a significant increase in both lumbar spine and total hip BMD, T-score and Z-score was reported (+11.5% in lumbar spine T-score; P<0.001), and there was a significant reduction in both CTX and BAP mean serum concentrations (-15% and -13%, respectively; P<0.001). Two (4.3%) patients had virological failure due to suboptimal adherence and one (2.2%) subject discontinued treatment due to a skin rash.

CONCLUSIONS

Switching virologically suppressed patients from tenofovir/emtricitabine plus one r/PI to raltegravir plus nevirapine after 48 weeks significantly improved proximal tubular function, increased BMD and reduced serum markers of bone turnover.

Effects of renal tubular dysfunction on bone in tenofovir-exposed HIV-positive patients

OBJECTIVES

Tenofovir disoproxil fumarate (TDF) may cause renal tubular dysfunction (RTD) and reduce bone mineral density (BMD). We examined the relationship between RTD and BMD in TDF-exposed HIV-positive men.

DESIGN AND METHODS

We analysed urinary retinol-binding protein/creatinine ratio (RBPCR) and fractional excretion of phosphate (FEPO4) to quantify RTD in a cross-sectional sample of randomly selected HIV-positive men at a single tertiary outpatient clinic. BMD at the lumbar spine and hip was measured by dual-energy X-ray absorptiometry. Multivariate logistic regression was used to analyse factors associated with RTD, and linear regression to examine the relationship between RTD and BMD.

RESULTS

Of 293 men (mean age 48 years, 94% White ethnicity, median TDF exposure 2.1 years), 22.5% had RBPCR-defined RTD and 12.3% had FEPO4-defined RTD. We observed a negative correlation between RBPCR and BMD at the spine (β -0.2, P = 0.002) and hip (total: β -0.1, P = 0.02; femoral neck: β -0.1, P = 0.02), but not between FePO4 and BMD. In multivariable analyses, RTD defined by more than five-fold elevations in RBPCR was associated with significantly lower BMD of the spine.

CONCLUSION

In HIV-positive patients receiving TDF-containing antiretroviral therapy, RTD was associated with lower BMD of the spine in HIV-positive men. RBPCR quantification may identify patients at increased risk of TDF-associated BMD loss.

Kidney dysfunction associated with tenofovir exposure in human immunodeficiency virus-1-infected Taiwanese patients

BACKGROUND/PURPOSE

Tenofovir disoproxil fumarate (TDF) is associated with kidney tubular dysfunction, for which the risk may vary among patients of different ethnicities. Data are limited, however, on the association between renal function changes and TDF exposure in human immunodeficiency virus (HIV)-infected Taiwanese patients.

METHODS

Medical records of HIV-infected Taiwanese patients seeking HIV care at a university hospital from 2011 to 2014 were reviewed. The change of estimated glomerular filtration rate (eGFR) was compared between patients not receiving combination antiretroviral therapy (cART) and those starting cART with or without TDF. The determinants of annual eGFR changes and factors associated with greater annual eGFR decline in TDF-exposed patients were explored.

RESULTS

A total of 775 patients were included: 140 were cART-naïve, 393 received TDF-containing cART, and 242 received cART without TDF. Compared with cART-naïve patients, the annual eGFR decline was greater in TDF-exposed patients (0.57 ± 8.6 mL/min/1.73 m² and 2.7 ± 8.9 mL/min/1.73 m², p = 0.012). The annual eGFR decline between patients receiving cART with or without TDF was similar (2.7 ± 8.9 mL/min/1.73 m² and 1.8 ± 8.3 mL/min/1.73 m², p = 0.567). Diabetes was associated with worsening eGFR decline in all studied patients. TDF exposure correlated with an additional annual eGFR decline of 2.73 mL/min/1.73 m² (95% confidence interval 0.139-5.326, p = 0.039) in patients with CD4 count < 350 cells/μL. Among TDF-exposed patients, the factors associated with annual eGFR decline of > 3 mL/min/1.73 m² were higher baseline eGFR and lower CD4 counts.

CONCLUSION

Among HIV-infected Taiwanese patients, cART exposure correlated with the decline of renal function. However, TDF-exposed patients are more likely to have prominent eGFR decline, especially those with higher baseline eGFR, advanced HIV disease, and diabetes.

Ageing with HIV: a multidisciplinary review

INTRODUCTION

After the introduction of highly active antiretroviral treatment, the course of HIV infection turned into a chronic disease and most of HIV-positive patients will soon be over 50 years old.

MATERIAL AND METHODS

This paper reviews the multiple aspects that physicians have to face while taking care of HIV-positive ageing patients including the definitions of frailty and the prevalence and risk factors of concomitant diseases. From a therapeutic point of view pharmacokinetic changes and antiretroviral-specific toxicities associated with ageing are discussed; finally therapeutic approaches to frailty are reviewed both in HIV-positive and negative patients.

CONCLUSION AND DISCUSSION

We conclude by suggesting that the combined use of drugs with the least toxicity potential and the promotion of healthy behaviours (including appropriate nutrition and exercise) might be the best practice for ageing HIV-positive subjects.

Raltegravir non-inferior to nucleoside based regimens in second-line therapy with lopinavir/ritonavir over 96 weeks: a randomised open label study for the treatment of HIV-1 infection

Objective

To determine the durability over 96 weeks of safety and efficacy of lopinavir/ritonavir (LPV/r) and raltegravir (RAL) which was demonstrated to have non-inferior efficacy relative to a regimen of LPV/r with nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs) (Control) in primary analysis at 48 weeks.

Design

Open label, centrally randomised trial.

Setting

Recruitment was from 37 primary and secondary care sites from Africa, Asia, Australia, Europe and Latin America.

Subjects

541 HIV-1 infected adults virologically failing first-line non-NRTI + 2N(t)RTI, with no previous exposure to protease inhibitors or integrase strand transfer inhibitors were analysed, 425 completed 96 weeks follow up on randomised therapy.

Intervention

Randomisation was 1:1 to Control or RAL.

Main outcome measures

Differences between the proportion of participants with plasma HIV-1 RNA (VL) <200 copies/mL by intention to treat were compared with a non-inferiority margin of −12%. Differences in biochemical, haematological and metabolic changes were assessed using T-tests.

Results

VL <200 copies/mL at 96 weeks was: RAL 80.4%, Control 76.0% (difference: 4.4 [95%CI −2.6, 11.3]) and met non-inferiority criteria. The RAL arm had a significantly higher mean change (difference Control-RAL; 95%CI) in haemoglobin (−2.9; −5.7, −1.1), total lymphocytes (−0.2; −0.3, −0.0), total cholesterol (−0.5; −0.8, −0.3), HDL cholesterol (−0.1; −0.1, −0.0) and LDL cholesterol (−0.3; −0.5, −0.2).

Conclusion

At 96 weeks, both RAL and Control maintained efficacy greater than 75% and continued to demonstrate similar safety profiles. These results support the use of a combination LPV/r and RAL regimen as an option following failure of 1st line NNRTI + 2N(t)RTIs.

Trial Registration

ClinicalTrials.gov NCT00931463

Integrase Strand Transfer Inhibitors in HIV Therapy

HIV drug resistance has been one of the major obstacles to HIV eradication and has contributed to the need for the constant development of new antiretroviral drugs over the past 25 years. With the recent approval of dolutegravir for human therapy by the U.S. Food and Drug Administration, health practitioners may soon have access to three integrase strand transfer inhibitors to treat individuals living with HIV. Here, we review the use of raltegravir, elvitegravir, and dolutegravir for use in first- and second-line HIV treatment regimens and the issue of HIV resistance against integrase inhibitors.