Inhibitory Effect of Etravirine, a Non-Nucleoside Reverse Transcriptase Inhibitor, via Anterior Gradient Protein 2 Homolog Degradation against Ovarian Cancer Metastasis

Anterior gradient protein 2 homolog (AGR2), an endoplasmic reticulum protein, is secreted in the tumor microenvironment. AGR2 is a member of the disulfide isomerase family, is highly expressed in multiple cancers, and promotes cancer metastasis. In this study, we found that etravirine, which is a non-nucleoside reverse transcriptase inhibitor, could induce AGR2 degradation via autophagy. Moreover, etravirine diminished proliferation, migration, and invasion in vitro. Moreover, in an orthotopic xenograft mouse model, the combination of etravirine and paclitaxel significantly suppressed cancer progression and metastasis. This drug may be a promising therapeutic agent for the treatment of ovarian cancer.

Dolutegravir or Darunavir in Combination with Zidovudine or Tenofovir to Treat HIV

BACKGROUND

The World Health Organization recommends dolutegravir with two nucleoside reverse-transcriptase inhibitors (NRTIs) for second-line treatment of human immunodeficiency virus type 1 (HIV-1) infection. Evidence is limited for the efficacy of this regimen when NRTIs are predicted to lack activity because of drug resistance, as well as for the recommended switch of an NRTI from tenofovir to zidovudine.

METHODS

In a two-by-two factorial, open-label, noninferiority trial, we randomly assigned patients for whom first-line therapy was failing (HIV-1 viral load, ≥1000 copies per milliliter) to receive dolutegravir or ritonavir-boosted darunavir and to receive tenofovir or zidovudine; all patients received lamivudine. The primary outcome was a week 48 viral load of less than 400 copies per milliliter, assessed with the Food and Drug Administration snapshot algorithm (noninferiority margin for the between-group difference in the percentage of patients with the primary outcome, 12 percentage points).

RESULTS

We enrolled 464 patients at seven sub-Saharan African sites. A week 48 viral load of less than 400 copies per milliliter was observed in 90.2% of the patients in the dolutegravir group (212 of 235) and in 91.7% of those in the darunavir group (210 of 229) (difference, -1.5 percentage points; 95% confidence interval [CI], -6.7 to 3.7; P = 0.58; indicating noninferiority of dolutegravir, without superiority) and in 92.3% of the patients in the tenofovir group (215 of 233) and in 89.6% of those in the zidovudine group (207 of 231) (difference, 2.7 percentage points; 95% CI, -2.6 to 7.9; P = 0.32; indicating noninferiority of tenofovir, without superiority). In the subgroup of patients with no NRTIs that were predicted to have activity, a viral load of less than 400 copies per milliliter was observed in more than 90% of the patients in the dolutegravir group and the darunavir group. The incidence of adverse events did not differ substantially between the groups in either factorial comparison.

CONCLUSIONS

Dolutegravir in combination with NRTIs was effective in treating patients with HIV-1 infection, including those with extensive NRTI resistance in whom no NRTIs were predicted to have activity. Tenofovir was noninferior to zidovudine as second-line therapy. (Funded by Janssen; NADIA ClinicalTrials.gov number, NCT03988452.).

Clinical Pharmacodynamics, Pharmacokinetics, and Drug Interaction Profile of Doravirine

Doravirine is a novel non-nucleoside reverse transcriptase inhibitor (NNRTI) that has demonstrated good efficacy, tolerability, and safety for the treatment of patients with human immunodeficiency virus (HIV)-1 infection in phase III clinical trials. Doravirine achieved non-inferiority when compared with efavirenz- and darunavir/ritonavir-based regimens. Fewer adverse effects, including neuropsychiatric effects were observed with doravirine compared with efavirenz. Key pharmacodynamic and pharmacokinetic characteristics as well as drug-drug interactions and the resistance profile were assessed in this clinical review. Doravirine is a pyridinone NNRTI with potent antiviral activity against wild-type HIV-1 virus and common NNRTI variants. Studies in healthy volunteers and HIV-infected individuals have shown that doravirine has a favorable pharmacokinetic profile for once-daily dosing, with an elimination half-life of around 15 h, median time to maximum plasma concentrations of 1-4 h, and time to steady-state concentration of 7 days. The pharmacokinetics of doravirine are not greatly influenced by sex, age, race, or hepatic impairment. Although no dose adjustment is required for doravirine in renal impairment when given as a single tablet, the fixed-dose combination tablet of doravirine/lamivudine/tenofovir disoproxil fumarate is not recommended in patients with a creatinine clearance of < 50 mL/min. Doravirine has a low potential for drug-drug interactions and does not impact on the pharmacokinetics of other drugs. However, it is metabolized via cytochrome P450 (CYP) 3A enzymes and is thus susceptible to interactions with CYP3A inhibitors and inducers. Strong CYP3A inhibitors can significantly increase doravirine exposure; however, this is not considered to be clinically relevant. Conversely, strong CYP3A inducers, such as rifampin, are contraindicated with doravirine owing to a significant reduction in exposure with potential for impaired virological efficacy. Moderate CYP3A inducers, such as rifabutin, may be co-administered if the doravirine dose is increased to 100 mg twice daily. Doravirine has a unique resistance profile and has demonstrated in vitro activity against some of the most common, clinically relevant NNRTI-resistant mutations. Prevalence of baseline NNRTI resistance to doravirine appears to be low in treatment-naïve cohorts. Further data on the efficacy of doravirine in patients with previous treatment experience and/or transmitted NNRTI resistance are required to further inform its place in the current armamentarium of drugs for the treatment of HIV infection.

Development of a pseudovirus assay and evaluation to screen natural products for inhibition of HIV-1 subtype C reverse transcriptase

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants are used in the management of Human Immunodeficiency Virus and Acquired Immunodeficiency Syndrome (HIV/AIDS) in many developing country settings where HIV-1 subtype C drives the epidemic. Efforts to identify plant derived molecules with anti-HIV properties require reproducible assay systems for routine screening of selected plant compounds. Although a number of standardized HIV-1 pseudoviruses have been generated to assess infectivity, replicability or reproducibility, HIV-1 subtype C (HIV-1-C) pseudoviruses have not been comprehensively characterized to identify inhibitory plant substances.

AIM OF THE STUDY

The current study aimed at developing an HIV-1-C pseudovirus assay, and evaluate plant substances targeting reverse transcriptase (RT) activity.

MATERIALS AND METHODS

HIV-1 subtype C pseudoviruses containing a luciferase reporter gene were generated by transfection of human 293T cells. HIV-1 subtype B (HIV-1-B) wild type pseudoviruses and mutants resistant to nucleoside and non-nucleoside RT inhibitors were also generated and used as controls. Selected plant substances and the RT inhibitors Zidovudine (AZT) and Nevirapine (NVP), were used to evaluate inhibition. Pseudovirus infectivity was determined by luciferase measurement in CF2/CD4⁺/CCR5 cells, and cytotoxicity was determined using the MTT assay. AZT and NVP inhibited wild type pseudoviruses in a dose dependent manner, with IC₅₀ values in the nanomolar range.

RESULTS

Pseudoviruses harbouring RT drug resistance mutations were poorly suppressed by AZT and NVP. Catechin, obtained from Peltophorum africanum inhibited HIV-1-C and HIV-1-B pseudoviruses with selective indices of 6304 μM (IC₅₀: 0.49 μM, CC₅₀: 3089 μM) and 1343 μM (IC₅₀: 2.3 μM, CC₅₀: 3089 μM), respectively; while the methanol root crude extract of Elaeodendron transvaalense gave IC₅₀ values of 11.11 μg/ml and 16.86 μg/ml, respectively.

CONCLUSION

The developed HIV-1-C pseudovirus assay can be used to screen plant substances for RT inhibition, and may have utility in settings with limited access to high level biosafety facilities.

A Clinical Metabolite of Azidothymidine Inhibits Experimental Choroidal Neovascularization and Retinal Pigmented Epithelium Degeneration

Purpose

Azidothymidine (AZT), a nucleoside reverse transcriptase inhibitor, possesses anti-inflammatory and anti-angiogenic activity independent of its ability to inhibit reverse transcriptase. The aim of this study was to evaluate the efficacy of 5'-glucuronyl azidothymidine (GAZT), an antiretrovirally inert hepatic clinical metabolite of AZT, in mouse models of retinal pigment epithelium (RPE) degeneration and choroidal neovascularization (CNV), hallmark features of dry and wet age-related macular degeneration (AMD), respectively.

Methods

RPE degeneration was induced in wild-type (WT) C57BL/6J mice by subretinal injection of Alu RNA. RPE degeneration was assessed by fundus photography and confocal microscopy of zonula occludens-1-stained RPE flat mounts. Choroidal neovascularization was induced by laser injury in WT mice, and CNV volume was measured by confocal microscopy. AZT and GAZT were delivered by intravitreous injections. Inflammasome activation was monitored by western blotting for caspase-1 and by ELISA for IL-1β in Alu RNA-treated bone marrow-derived macrophages (BMDMs).

Results

GAZT inhibited Alu RNA-induced RPE degeneration and laser-induced CNV. GAZT also reduced Alu RNA-induced caspase-1 activation and IL-1β release in BMDMs.

Conclusions

GAZT possesses dual anti-inflammatory and anti-angiogenic properties and could be a viable treatment option for both forms of AMD.

Doravirine/Lamivudine/Tenofovir Disoproxil Fumarate is Non-inferior to Efavirenz/Emtricitabine/Tenofovir Disoproxil Fumarate in Treatment-naive Adults With Human Immunodeficiency Virus-1 Infection: Week 48 Results of the DRIVE-AHEAD Trial

Background

Doravirine (DOR), a novel non-nucleoside reverse-transcriptase inhibitor (NNRTI), is active against wild-type Human Immunodeficiency Virus (HIV)-1 and the most common NNRTI-resistant variants, and has a favorable and unique in vitro resistance profile.

Methods

DRIVE-AHEAD is a phase 3, double-blind, non-inferiority trial. Antiretroviral treatment–naive adults with ≥1000 HIV-1 RNA copies/mL were randomized (1:1) to once-daily, fixed-dose DOR at 100 mg, lamivudine at 300 mg, and tenofovir disoproxil fumarate (TDF) at 300 mg (DOR/3TC/TDF) or to efavirenz at 600 mg, emtricitabine at 200 mg, and TDF at 300 mg (EFV/FTC/TDF) for 96 weeks. The primary efficacy endpoint was the proportion of participants with <50 HIV-1 RNA copies/mL at week 48 (Food and Drug Administration snapshot approach; non-inferiority margin 10%).

Results

Of the 734 participants randomized, 728 were treated (364 per group) and included in the analyses. At week 48, 84.3% (307/364) of DOR/3TC/TDF recipients and 80.8% (294/364) of EFV/FTC/TDF recipients achieved <50 HIV-1 RNA copies/mL (difference 3.5%, 95% CI, -2.0, 9.0). DOR/3TC/TDF recipients had significantly lower rates of dizziness (8.8% vs 37.1%), sleep disorders/disturbances (12.1% vs 25.2%), and altered sensorium (4.4% vs 8.2%) than EFV/FTC/TDF recipients. Mean changes in fasting low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) were significantly different between DOR/3TC/TDF and EFV/FTC/TDF (−1.6 vs +8.7 mg/dL and −3.8 vs +13.3 mg/dL, respectively).

Conclusions

In HIV-1 treatment-naive adults, DOR/3TC/TDF demonstrated non-inferior efficacy to EFV/FTC/TDF at week 48 and was well tolerated, with significantly fewer neuropsychiatric events and minimal changes in LDL-C and non–HDL-C compared with EFV/FTC/TDF.

Clinical Trials Registration

NCT02403674

Is Antiretroviral Two-Drug Regimen the New Standard for HIV Treatment in Naive Patients?

The use of a combination antiretroviral therapy (cART) has changed dramatically the prognosis and the life expectancy of people living with HIV. The current treatment guidelines continue the convention of preferred cART based on combining a dual nucleoside reverse-transcriptase inhibitor (NRTI) backbone with a third "anchor" agent, such as a ritonavir (r)- or cobicistat (c)-boosted protease inhibitor (PI), a non-NRTI (NNRTI), or an integrase inhibitor (INI) boosted or unboosted. However, due to toxicities of NRTIs, sparing NRTI regimen has been studied for a long time with moderate success due to low efficacy (especially in patients with high viral load and low CD4) compare to standard triple therapy. New strategy with lamivudine (3TC) plus a boosted PI or INI showed promise results and indicated that modern two-drug regimens might now, in fact, become a reliable treatment for HIV-infected naïve patients. This article discusses recent data from dual therapy studies in naïve HIV-infected patients and the challenges behind this strategy.

Using PBPK Modeling to Predict Drug Exposure and Support Dosage Adjustments in Patients With Renal Impairment: An Example with Lamivudine

BACKGROUND

Lamivudine is a nucleoside reverse transcriptase inhibitor used to treat HIV and hepatitis B. It is primarily cleared by the kidney with renal secretion mediated by OCT2 and MATE.

OBJECTIVE

To use PBPK modeling to assess the impact of renal impairment on lamivudine pharmacokinetics using the Simcyp® Simulator.

METHODS

The model incorporated the Simcyp® Mechanistic Kidney Model option to predict renal disposition. The model was initially verified using the Simcyp® Healthy Volunteer population. Two discrete patient populations were then created for moderate (GFR 10-40 mL/min) and severe (GFR < 10 mL/min) renal failure (RF), and model simulations were compared to published data. The developed model was then utilized in a clinical study evaluating the clinical experience and plasma exposure of lamivudine when administered at higher than recommended doses to HIV-infected patients with varying degrees of renal impairment.

RESULTS

Predicted systemic exposure metrics (Cmax, AUC) compared favorably to published clinical data for each population, with the following fold errors (FE, ratio of predicted and observed data) for Cmax/AUC: Healthy Volunteers 1.04/1.04, Moderate RF 1.03/0.78, Severe RF 0.89/0.79. The model captured lamivudine plasma concentrations measured pre- and post-dose (0.5-1.5hr) in study participants (n = 34). Model simulations demonstrated comparable systemic profiles across patient cohorts, supporting the proposed dosage adjustment scheme.

CONCLUSION

This study illustrates how PBPK modeling can help verify dosing guidelines for patients with varying levels of renal impairment. This approach may also be useful for predicting potential changes in exposure during renal insufficiency for compounds undergoing clinical development.

Safety and pharmacokinetics of dolutegravir in pregnant mothers with HIV infection and their neonates: A randomised trial (DolPHIN-1 study)

BACKGROUND

The global transition to use of dolutegravir (DTG) in WHO-preferred regimens for HIV treatment is limited by lack of knowledge on use in pregnancy. Here we assessed the relationship between drug concentrations (pharmacokinetics, PK), including in breastmilk, and impact on viral suppression when initiated in the third trimester (T3).

METHODS AND FINDINGS

In DolPHIN-1, HIV-infected treatment-naïve pregnant women (28-36 weeks of gestation, age 26 (19-42), weight 67kg (45-119), all Black African) in Uganda and South Africa were randomised 1:1 to dolutegravir (DTG) or efavirenz (EFV)-containing ART until 2 weeks post-partum (2wPP), between 9th March 2017 and 16th January 2018, with follow-up until six months postpartum. The primary endpoint was pharmacokinetics of DTG in women and breastfed infants; secondary endpoints included maternal and infant safety and viral suppression. Intensive pharmacokinetic sampling of DTG was undertaken at day 14 and 2wPP following administration of a medium-fat breakfast, with additional paired sampling between maternal plasma and cord blood, breastmilk and infant plasma. No differences in median baseline maternal age, gestation (31 vs 30 weeks), weight, obstetric history, viral load (4.5 log10 copies/mL both arms) and CD4 count (343 vs 466 cells/mm3) were observed between DTG (n = 29) and EFV (n = 31) arms. Although DTG Ctrough was below the target 324ng/mL (clinical EC90) in 9/28 (32%) mothers in the third trimester, transfer across the placenta (121% of plasma concentrations) and into breastmilk (3% of plasma concentrations), coupled with slower elimination, led to significant infant plasma exposures (3-8% of maternal exposures). Both regimens were well-tolerated with no significant differences in frequency of adverse events (two on DTG-ART, one on EFV-ART, all considered unrelated to drug). No congenital abnormalities were observed. DTG resulted in significantly faster viral suppression (P = 0.02) at the 2wPP visit, with median time to <50 copies/mL of 32 vs 72 days. Limitations related to the requirement to initiate EFV-ART prior to randomisation, and to continue DTG for only two weeks postpartum.

CONCLUSION

Despite low plasma DTG exposures in the third trimester, transfer across the placenta and through breastfeeding was observed in this study, with persistence in infants likely due to slower metabolic clearance. HIV RNA suppression <50 copies/mL was twice as fast with DTG compared to EFV, suggesting DTG has potential to reduce risk of vertical transmission in mothers who are initiated on treatment late in pregnancy.

TRIAL REGISTRATION

clinicaltrials.gov NCT02245022.

Third-line antiretroviral therapy in low-income and middle-income countries (ACTG A5288): a prospective strategy study

BACKGROUND

Antiretroviral therapy (ART) management is challenging for individuals in resource-limited settings presenting for third-line treatment because of complex resistance patterns, partly due to reduced access to viral load monitoring. We aimed to evaluate use of newer antiretroviral drugs and contemporary management approaches, including population-based sequencing, to select appropriate antiretrovirals, plasma viral load monitoring, and interventions to improve adherence in individuals presenting with second-line viral failure.

METHODS

A5288 was a phase 4, third-line ART strategy study done at 19 urban sites in ten countries that enrolled adult participants with confirmed plasma HIV-1 RNA (viral load) of 1000 copies per mL or more after more than 24 weeks of protease inhibitor-based second-line ART. The primary objective was to use antiretrovirals (raltegravir, etravirine, and ritonavir-boosted darunavir) and diagnostic monitoring technologies, including viral load, genotyping, and adherence support to achieve viral load suppression (defined as ≤200 copies per mL) in 65% or more of participants. ART history and real-time drug resistance genotypes were used to assign participants to one of four cohorts: cohort A (no lopinavir resistance) stayed on second-line ART and cohorts B (B1, best available nucleoside reverse transcriptase inhibitors [NRTIs] plus ritonavir-boosted darunavir plus raltegravir; B2, ritonavir-boosted darunavir plus raltegravir plus etravirine; B3, ritonavir-boosted darunavir, raltegravir, and either tenofovir plus emtricitabine or tenofovir plus lamivudine), C (ritonavir-boosted darunavir plus raltegravir plus tenofovir-emtricitabine or tenofovir plus lamivudine), and D (best available NRTIs plus ritonavir-boosted darunavir plus raltegravir) were defined by increasing levels of resistance and received appropriate regimens, including new antiretrovirals. Participants in Cohort B without detectable hepatitis B surface antigen were assigned by blocked randomisation to cohorts B1 and B2, and those with detectable hepatitis B surface antigen were assigned to cohort B3. The trial is registered with ClinicalTrials.gov, number NCT01641367.

FINDINGS

From Jan 10, 2013, to Sept 10, 2015, 545 participants were enrolled. 287 (53%) were assigned to cohort A, 74 (14%) to B1, 72 (13%) to B2, eight (1%) to B3, 70 (13%) to C, and 34 (6%) to D. Overall, 349 (64%, 95% CI 60-68) participants achieved viral suppression at week 48, with proportions varying from 125 (44%) of 287 in cohort A to 65 (88%) of 74 in cohort B1, 63 (88%) of 72 in B2, eight (100%) of eight in B3, 63 (90%) of 70 in C, and 25 (74%) of 34 in D. Participants in cohort A remained on their second-line protease inhibitor, and had the most participants with grade 3 or higher adverse events (147 [51%]).

INTERPRETATION

Targeted real-time genotyping to select third-line ART can appropriately allocate more costly antiretrovirals to those with greater levels of HIV drug resistance.

FUNDING

National Institutes of Health.

Non-nucleoside reverse transcriptase inhibitor levels among HIV-exposed uninfected infants at the time of HIV PCR testing - findings from a tertiary healthcare facility in Pretoria, South Africa

INTRODUCTION

To date, very little programmatic data has been published regarding serial antiretroviral (ARV) levels in infants exposed to maternal treatment and/or infant prophylaxis during the first months of life. Such data provide the opportunity to describe the proportion of infants exposed to virologically suppressive levels of ARVs and to gauge adherence to the prevention of mother-to-child transmission of HIV (PMTCT) programme.

METHODS

From August 2014 to January 2016, HIV-exposed infants born at Kalafong Provincial Tertiary Hospital in Pretoria, South Africa were enrolled as part of an observational cohort study. Plasma samples from HIV-exposed uninfected infants were obtained at birth, 6-weeks, 10-weeks and 14-weeks of age and quantitative efavirenz (EFV) and nevirapine (NVP) drug level testing performed using liquid chromatography-mass spectrometry, irrespective of maternal ARV regimen. Descriptive analysis of EFV and NVP levels in relation to self-reported maternal and infant ARV exposure was performed. EFV levels >500 ng/mL and NVP levels >100 ng/mL were reported based on studies suggesting that trough levels above these thresholds are associated with virological suppression and PMTCT respectively.

RESULTS

Among 66 infants exposed to maternal EFVin utero, 29 (44%) had virologically suppressive plasma EFV levels at birth, with a median level of 1665 ng/mL (IQR: 1094 to 3673). Among infants who were exclusively breastfed at 6-, 10- and 14 weeks, 13/48 (27%), 5/25 (25%) and 0/21 (0%) had virologically suppressive EFV levels. Among 64 infants whose mothers reported administering daily infant NVP at time of their 6-week HIV PCR test, only 45 (70%) had NVP levels above the minimum prophylactic trough level.

CONCLUSIONS

During the first 10-weeks after delivery, a quarter of breastfed infants born to women on an EFV-containing treatment regimen maintained virologically suppressive EFV plasma levels. This finding highlights the importance of both careful monitoring of ARV side effects and repeat HIV PCR after the first few months of life among HIV-exposed uninfected infants. As 30% of infants had inadequate NVP plasma levels at 6-weeks of age, adherence counselling to caregivers regarding infant prophylaxis needs to be enhanced to further reduce mother-to-child transmission of HIV.

Predictors of Therapeutic Outcome to Nucleotide Reverse Transcriptase Inhibitor in Hepatitis B Patients

Hepatitis B is a clinically important public health issue. Infection leads to hepatocellular carcinoma. Therefore, patients need antiviral therapy for prolonged period to prevent the complication of the disease. Data concerning chronic hepatitis B (CHB) patients with high hepatitis B virus (HBV) DNA are limited. The aim of the study was to check the efficacy of the nucleoside reverse transcriptase inhibitors (tenofovir) in terms of suppression of HBV DNA. The secondary end point in the study is to evaluate trends of predictive variables that predict outcome of treatment. In this specific study, we evaluated 140 CHB male and female patients, of these 110 completed 48 weeks of treatment. On the basis of hepatitis B e antigen (HBeAg), patients were stratified; HBV DNA and hepatitis B surface antigen (HBsAg) levels were measured along with liver function tests. All enrolled patients were given tenofovir disoproxil fumarate 300 mg daily before breakfast. Overall, 69.1% of patients showed virologic response. HBeAg-negative patient group showed 68% viral suppression and HBeAg-positive patient group showed 45.9% over 24 months of treatment, while at 48 months it was shown to be 76.7% and 54.1%, respectively. None of the patients suffered HBsAg loss during the 48 months. Baseline high HBV DNA level was found as a significant predictor of response (OR, 1.9; 95% CI = 1.23-3.9, p = 0.005). None of the patients observed had serious adverse events. Mutations in the RT region of polymerase gene are shown to be associated with resistance to antiviral drugs. Among patients suffering with chronic HBV infection, HBeAg-negative patient group have better virologic response as compared with HBeAg-positive group. Higher concentration of HBV DNA at baseline has negative prediction for sustained viral suppression. The A-B motif interdomain rtL122F mutation was found in nonresponder patients in our study. Another mutation rtN248H observed in E motif considered to have effect on DNA primer grip, which forms part of binding pocket.

Drug metabolism and transport gene polymorphisms and efavirenz adverse effects in Brazilian HIV-positive individuals

Objectives

There are limited data regarding efavirenz pharmacogenetics in admixed populations. The Brazilian population is highly admixed. In a Brazilian cohort, we sought to characterize associations between efavirenz adverse effects (all-cause and CNS) and polymorphisms in seven genes known or suspected to affect efavirenz metabolism and transport.

Methods

We studied 225 HIV-positive individuals who had been prescribed efavirenz-containing regimens at a hospital in Rio de Janeiro, Brazil. Eighty-nine cases had efavirenz adverse effects, including 43 with CNS adverse effects, while 136 controls had no adverse effect of any antiretroviral after treatment for at least 6 months. A total of 67 candidate polymorphisms in ABCB1, CYP2A6, CYP2B6, CYP3A4, CYP3A5, NR1I2 and NR1I3 genes were selected for association analysis. Admixture was assessed using 28 ancestry-informative polymorphisms previously validated for the Brazilian population. Associations were evaluated with logistic regression models adjusted for sex and genetic ancestry.

Results

There was extensive African, European and Native American admixture in the cohort. Increased all-cause adverse effects were associated with the CYP2B6 genotype combination 15582CC-516TT-983TT (OR = 7.26, P = 0.003) and with the CYP2B6 slow metabolizer group 516TT or 516GT-983CT (OR = 3.10, P = 0.04). CNS adverse effects were nominally associated with CYP3A4 rs4646437 (OR = 4.63, P = 0.014), but not after adjusting for multiple comparisons.

Conclusions

In a highly admixed Brazilian cohort, the CYP2B6 slow metabolizer genotype was associated with an increased risk of efavirenz adverse effects.

Day-On, Day-Off emtricitabine, tenofovir disoproxil fumarate and efavirenz single tablet regimen (DODO) as maintenance therapy in HIV-infected patients

Reduced dose schedules may be feasible options to simplify antiretroviral therapy (ART) in selected HIV-1-infected individuals. Efficacy and safety of a Day-on, Day-off (DODO) schedule of tenofovir disoproxil fumarate, emtricitabine and efavirenz (FTC/TDF/EFV) single tablet regimen (STR) was assessed. Twenty-seven patients were prescribed the DODO schedule and were monitored for 48 weeks. Switching criteria were: no previous ART failure, no AIDS-defining illnesses, T CD4 cell nadir >200/mmc, and HIV-RNA below detection limit (40 copies/mL) for at least six months. Clinical and laboratory data, including plasma HIV-RNA levels, T CD4 and CD8 counts, liver and kidney function, lipid levels and ultrasensitive C-reactive protein (us-CRP) were assessed at baseline, week 4, 12, 24, and 48. Statistical analysis was performed by paired Student's T-test for comparison between baseline and each time point and Chi square test for CD4/CD8 ratio comparison. In all, 26 out of 27 patients maintained plasma HIV-RNA levels below the detection limit through the entire follow-up. One patient experienced low level plasma HIV-RNA rebound at week 36 (47 copies/ml) and immediately reverted to the conventional dose schedule of FTC/TDF/EFV; plasma HIV-RNA was undetectable after four weeks. No major changes on liver and kidney function tests, lipid levels and us-CRP were observed. Although no profound modifications of T CD4 count were observed during follow-up, the CD4/CD8 ratio increased significantly at week 48 compared to the baseline (p<0.05). In conclusion, 48-week DODO administration of the fixed dose FTC/TDF/EFV STR combination was safe and effective in maintaining HIV viral replication below the detection limit in a selected group of HIV-1-infected individuals.

Emerging reverse transcriptase inhibitors for HIV-1 infection

INTRODUCTION

There are 36.7 million people living with HIV with 20.9 million having access to antiretroviral therapy (ART). Nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) remain the 'backbone' of ART. However, the currently available nine NRTIs and five non-nucleoside reverse transcriptase inhibitors (NNRTIs) have significant side effects and resistance profiles. Areas covered: We summarize the mechanisms of resistance and other limitations of the existing NRTIs/NNRTIs. GS-9131, MK-8591, Elsulfavirine and Doravirine are four new agents that are furthest along in development. Expert opinion: ART development has evolved with several new promising agents. Longer-acting agents, like MK-8591 are extremely attractive to enhance drug adherence and patient satisfaction. Doravirine offers an NNRTI effective against common mutations that has fewer side effects, limitations on dosing and drug interactions. GS-9131 is very potent and active against a variety of NRTI mutants but it is too early in its development to understand its full risks and benefits. Finally, Elsulfavirine has a long half-life and preliminary data suggests fewer side effects than the most commonly used NNRTI, efavirenz. Each of these new agents shows promise and potential to improve ART in the future. The newer generation of reverse transcriptase inhibitors have longer half-lives, more favorable adverse effect profiles, and fewer drug interactions.

Removing inactive NRTIs in a salvage regimen is safe, maintains virological suppression and reduces treatment costs: results from the VERITAS study (TMC114HIV4054)

BACKGROUND

Despite the benefit of maintaining inactive Nucleotide/side reverse transcriptase inhibitors (NRTIs) in salvage regimens, they are associated with increased toxicity and treatment costs. Current evidence suggests that NRTI-sparing regimens in patients failing ART are non-inferior to NRTI-including regimens. This study aimed to evaluate the impact of removing at least one inactive NRTI on virologic, safety, and financial outcomes.

METHODS

Drug-resistant, virologically suppressed patients with CD4 >250 cells/ml on a stable regimen of four or more antiretrovirals (ARVs) were enrolled in a 48-week prospective, open-label pilot trial. One inactive NRTI was removed at baseline. Patients taking over five ARVs had a second inactive NRTI removed at 24 weeks. Viral load, CD4 count, and adverse events were assessed at baseline, 24, and 48 weeks.

RESULTS

Thirty-one male patients participated. Twenty-nine (94%) patients had lamivudine (3TC) or emtricitabine (FTC) removed and four patients had an additional NRTI removed. One patient was excluded at week 26 for discontinuing an active NRTI. All patients maintained undetectable viral loads at weeks 24 (100%) and 48 [PP = 100%; Intent-to-treat (ITT) = 97%]. At 48 weeks, patients had a median gain of 20 CD4 (IQR: - 50, +133; mean +39) compared to baseline. Three patients exhibited Grade III bilirubin elevation (two Grade II and one Grade III at baseline), which returned to baseline levels. No serious adverse events were observed. Removal of one or two ARVs equated to a mean annual savings of $3319 CDN (11%) and $8630 CDN (24%), respectively.

CONCLUSION

Removing inactive NRTIs in patients with a controlled viral load appears to be safe, maintains virological suppression, and reduces treatment costs.

Incident AIDS or Death After Initiation of Human Immunodeficiency Virus Treatment Regimens Including Raltegravir or Efavirenz Among Adults in the United States

Background.

The long-term effectiveness of human immunodeficiency virus (HIV) treatments containing integrase inhibitors is unknown.

Methods.

We use observational data from the Centers for AIDS Research Network of Integrated Clinical Systems and the Centers for Disease Control and Prevention to estimate 4-year risk of AIDS and all-cause mortality among 415 patients starting a raltegravir regimen compared to 2646 starting an efavirenz regimen (both regimens include emtricitabine and tenofovir disoproxil fumarate). We account for confounding and selection bias as well as generalizability by standardization for measured variables, and present both observational intent-to-treat and per-protocol estimates.

Results.

At treatment initiation, 12% of patients were female, 36% black, 13% Hispanic; median age was 37 years, CD4 count 321 cells/µL, and viral load 4.5 log10 copies/mL. Two hundred thirty-five patients incurred an AIDS-defining illness or died, and 741 patients left follow-up. After accounting for measured differences, the 4-year risk was similar among those starting both regimens (ie, intent-to treat hazard ratio [HR], 0.96 [95% confidence interval {CI}, .63-1.45]; risk difference, -0.9 [95% CI, -4.5 to 2.7]), as well as among those remaining on regimens (ie, per-protocol HR, 0.95 [95% CI, .59-1.54]; risk difference, -0.5 [95% CI, -3.8 to 2.9]).

Conclusions.

Raltegravir and efavirenz-based initial antiretroviral therapy have similar 4-year clinical effects. Vigilance regarding longer-term comparative effectiveness of HIV regimens using observational data is needed because large-scale experimental data are not forthcoming.

Implementing Generalized Additive Models to Estimate the Expected Value of Sample Information in a Microsimulation Model: Results of Three Case Studies

BACKGROUND

The expected value of sample information (EVSI) can help prioritize research but its application is hampered by computational infeasibility, especially for complex models. We investigated an approach by Strong and colleagues to estimate EVSI by applying generalized additive models (GAM) to results generated from a probabilistic sensitivity analysis (PSA).

METHODS

For 3 potential HIV prevention and treatment strategies, we estimated life expectancy and lifetime costs using the Cost-effectiveness of Preventing AIDS Complications (CEPAC) model, a complex patient-level microsimulation model of HIV progression. We fitted a GAM-a flexible regression model that estimates the functional form as part of the model fitting process-to the incremental net monetary benefits obtained from the CEPAC PSA. For each case study, we calculated the expected value of partial perfect information (EVPPI) using both the conventional nested Monte Carlo approach and the GAM approach. EVSI was calculated using the GAM approach.

RESULTS

For all 3 case studies, the GAM approach consistently gave similar estimates of EVPPI compared with the conventional approach. The EVSI behaved as expected: it increased and converged to EVPPI for larger sample sizes. For each case study, generating the PSA results for the GAM approach required 3 to 4 days on a shared cluster, after which EVPPI and EVSI across a range of sample sizes were evaluated in minutes. The conventional approach required approximately 5 weeks for the EVPPI calculation alone.

CONCLUSION

Estimating EVSI using the GAM approach with results from a PSA dramatically reduced the time required to conduct a computationally intense project, which would otherwise have been impractical. Using the GAM approach, we can efficiently provide policy makers with EVSI estimates, even for complex patient-level microsimulation models.

Lopinavir plus nucleoside reverse-transcriptase inhibitors, lopinavir plus raltegravir, or lopinavir monotherapy for second-line treatment of HIV (EARNEST): 144-week follow-up results from a randomised controlled trial

BACKGROUND

Millions of HIV-infected people worldwide receive antiretroviral therapy (ART) in programmes using WHO-recommended standardised regimens. Recent WHO guidelines recommend a boosted protease inhibitor plus raltegravir as an alternative second-line combination. We assessed whether this treatment option offers any advantage over the standard protease inhibitor plus two nucleoside reverse-transcriptase inhibitors (NRTIs) second-line combination after 144 weeks of follow-up in typical programme settings.

METHODS

We analysed the 144-week outcomes at the completion of the EARNEST trial, a randomised controlled trial done in HIV-infected adults or adolescents in 14 sites in five sub-Saharan African countries (Uganda, Zimbabwe, Malawi, Kenya, Zambia). Participants were those who were no longer responding to non-NRTI-based first-line ART, as assessed with WHO criteria, confirmed by viral-load testing. Participants were randomly assigned to receive a ritonavir-boosted protease inhibitor (lopinavir 400 mg with ritonavir 100 mg, twice per day) plus two or three clinician-selected NRTIs (protease inhibitor plus NRTI group), protease inhibitor plus raltegravir (400 mg twice per day; protease inhibitor plus raltegravir group), or protease inhibitor monotherapy (plus raltegravir induction for first 12 weeks, re-intensified to combination therapy after week 96; protease inhibitor monotherapy group). Randomisation was by computer-generated randomisation sequence, with variable block size. The primary outcome was viral load of less than 400 copies per mL at week 144, for which we assessed non-inferiority with a one-sided α of 0·025, and superiority with a two-sided α of 0·025. The EARNEST trial is registered with ISRCTN, number 37737787.

FINDINGS

Between April 12, 2010, and April 29, 2011, 1837 patients were screened for eligibility, of whom 1277 patients were randomly assigned to an intervention group. In the primary (complete-case) analysis at 144 weeks, 317 (86%) of 367 in the protease inhibitor plus NRTI group had viral loads of less than 400 copies per mL compared with 312 (81%) of 383 in the protease inhibitor plus raltegravir group (p=0·07; lower 95% confidence limit for difference 10·2% vs specified non-inferiority margin 10%). In the protease inhibitor monotherapy group, 292 (78%) of 375 had viral loads of less than 400 copies per mL; p=0·003 versus the protease inhibitor plus NRTI group at 144 weeks. There was no difference between groups in serious adverse events, grade 3 or 4 adverse events (total or ART-related), or events that resulted in treatment modification.

INTERPRETATION

Protease inhibitor plus raltegravir offered no advantage over protease inhibitor plus NRTI in virological efficacy or safety. In the primary analysis, protease inhibitor plus raltegravir did not meet non-inferiority criteria. A regimen of protease inhibitor with NRTIs remains the best standardised second-line regimen for use in programmes in resource-limited settings.

FUNDING

European and Developing Countries Clinical Trials Partnership (EDCTP), UK Medical Research Council, Instituto de Salud Carlos III, Irish Aid, Swedish International Development Cooperation Agency, Instituto Superiore di Sanita, Merck, ViiV Healthcare, WHO.

Nanoparticle-releasing nanofiber composites for enhanced in vivo vaginal retention

Current approaches for topical vaginal administration of nanoparticles result in poor retention and extensive leakage. To overcome these challenges, we developed a nanoparticle-releasing nanofiber delivery platform and evaluated its ability to improve nanoparticle retention in a murine model. We individually tailored two components of this drug delivery system for optimal interaction with mucus, designing (1) mucoadhesive fibers for better retention in the vaginal tract, and (2) PEGylated nanoparticles that diffuse quickly through mucus. We hypothesized that this novel dual-functioning (mucoadhesive/mucus-penetrating) composite material would provide enhanced retention of nanoparticles in the vaginal mucosa. Equivalent doses of fluorescent nanoparticles were vaginally administered to mice in either water (aqueous suspension) or fiber composites, and fluorescent content was quantified in cervicovaginal mucus and vaginal tissue at time points from 24 h to 7d. We also fabricated composite fibers containing etravirine-loaded nanoparticles and evaluated the pharmacokinetics over 7d. We found that our composite materials provided approximately 30-fold greater retention of nanoparticles in the reproductive tract at 24 h compared to aqueous suspensions. Compared to nanoparticles in aqueous suspension, the nanoparticles in fiber composites exhibited sustained and higher etravirine concentrations after 24 h and up to 7d, demonstrating the capabilities of this new delivery platform to sustain nanoparticle release out to 3d and drug retention out to one week after a single administration. This is the first report of nanoparticle-releasing fibers for vaginal drug delivery, as well as the first study of a single delivery system that combines two components uniquely engineered for complementary interactions with mucus.

Optimization of tenofovir release from mucoadhesive vaginal tablets by polymer combination to prevent sexual transmission of HIV

The use of sustained-release mucoadhesive vaginal tablets of antiretroviral drugs as microbicidal formulations can be an effective strategy for reducing the sexual transmission of HIV from men to women, which is a main problem particularly in low- and middle-income countries. Different polymers (hydroxypropylmethyl cellulose (HPMC), chitosan, guar gum and Eudragit^® RS) have proven some good features for this purpose. At this work, these polymers have been combined in pairs in different proportions to enhance the advantages offered by each one individually. The in vitro release of tenofovir from the matrices, ex vivo mucoadhesive capacity (evaluated on vaginal mucosa) and the degree of swelling in simulated vaginal fluid have been assessed. A multimodal pore size distribution is observed in porosimetry studies -carried out with swelling witnesses-, due to the contribution of polymers with different swelling behaviour to the pore formation, and it is corroborated by scanning electron microscopy. X-ray diffraction technique confirms the changes in crystallinity of the formulation after swelling. We can report that the combination of HPMC and chitosan in the same formulation may be useful for the prevention of sexual transmission of HIV, since tablets can be obtained that remain adhered to the vaginal mucosa for 96h, so the drug is released in a sustained manner for 72h. When the formulation contains more chitosan than HPMC the swelling is moderate, making it more comfortable for women to apply.

Regimen Change: Gilead's TAF Drugs Toppling TDFs in HIV Treatment

Truvada is getting a new lease on life as a preventive agent. It is the only drug approved to prevent HIV infections, and Truvada is the key pharmaceutical component of pre-exposure prophylaxis, which is aimed at preventing, rather than treating, HIV infection and transmission.

Antiretroviral Therapy With Efavirenz Accentuates Pregnancy-Associated Reduction of Dihydroartemisinin-Piperaquine Exposure During Malaria Chemoprevention

Dihydroartemisinin (DHA)-piperaquine is promising for malaria chemoprevention in pregnancy. We assessed the impacts of pregnancy and efavirenz-based antiretroviral therapy on exposure to DHA and piperaquine in pregnant Ugandan women. Intensive sampling was performed at 28 weeks gestation in 31 HIV-uninfected pregnant women, in 27 HIV-infected pregnant women receiving efavirenz, and in 30 HIV-uninfected nonpregnant women. DHA peak concentration and area under the concentration time curve (AUC0-8hr ) were 50% and 47% lower, respectively, and piperaquine AUC0-21d was 40% lower in pregnant women compared to nonpregnant women. DHA AUC0-8hr and piperaquine AUC0-21d were 27% and 38% lower, respectively, in pregnant women receiving efavirenz compared to HIV-uninfected pregnant women. Exposure to DHA and piperaquine were lower among pregnant women and particularly in women on efavirenz, suggesting a need for dose modifications. The study of modified dosing strategies for these populations is urgently needed.

Sub-therapeutic nevirapine concentration during antiretroviral treatment initiation among children living with HIV: Implications for therapeutic drug monitoring

Nevirapine, a component of antiretroviral therapy (ART) in resource-limited settings, known for auto-induction of metabolism, is initiated at half therapeutic dose until day 14 (‘lead-in period’), and subsequently escalated to full dose. However, studies have shown that this dosing strategy based on adult studies may not be appropriate in children, given that younger children have higher drug clearance rates. In this prospective cohort study, we studied trough plasma nevirapine levels by high performance liquid chromatography (HPLC) at days 7, 14 (lead-in period) and 28 (full dose period) after ART initiation amongst HIV-1 infected children initiating nevirapine-based ART in southern India. Among the 20 children (50% male, median age 9 years) included in the study, sub-therapeutic trough plasma nevirapine concentration (<4μg/ml) was seen in 65% (13/20) of children during the lead-in period within two weeks of ART initiation and among 10% of children at 4 weeks during full-dose nevirapine. Adherence was documented as ≥95% in all children by both caregiver self-report and pill count. Median nevirapine concentrations achieved at week 1 was 4.8 μg/ml, significantly lower than 8 μg/ml, the concentration achieved at week 4 (p = 0.034). Virological failure at one year of ART was observed in six children, and was not associated with median nevirapine concentration achieved during week 1, 2 or 4. We conclude that the dose escalation strategy currently practiced among young children living with HIV-1 resulted in significant subtherapeutic nevirapine concentration (≤4μg/ml) during the lead-in period. We call for a closer look at pediatric-focused dosing strategies for nevirapine initiation in young children. Further studies to establish age-appropriate threshold nevirapine concentration are warranted in young children to corroborate the role of therapeutic drug monitoring in predicting virological outcome.

Comparative efficacy and safety of second-line antiretroviral therapy for treatment of HIV/AIDS: a systematic review and network meta-analysis

BACKGROUND

Selection of optimal second-line antiretroviral therapy (ART) has important clinical and programmatic implications. To inform the 2016 revision of the WHO ART guidelines, we assessed the comparative effectiveness and safety of available second-line ART regimens for adults and adolescents in whom first-line non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens have failed.

METHODS

In this systematic review and network meta-analysis, we searched for randomised controlled trials and prospective and retrospective cohort studies that evaluated outcomes in treatment-experienced adults living with HIV who switched ART regimen after failure of a WHO-recommended first-line NNRTI-based regimen. We searched Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials for reports published from Jan 1, 1996, to Aug 8, 2016, and searched conference abstracts published from Jan 1, 2014, to Aug 8, 2016. Outcomes of interest were viral suppression, mortality, AIDS-defining illnesses or WHO stage 3-4 disease, discontinuations, discontinuations due to adverse events, and serious adverse events. We assessed comparative efficacy and safety in a network meta-analysis, using Bayesian hierarchical models.

FINDINGS

We identified 12 papers pertaining to eight studies, including 4778 participants. The network was centred on ritonavir-boosted lopinavir plus two nucleoside or nucleotide reverse transcriptase inhibitors. Ritonavir-boosted lopinavir monotherapy was the only regimen inferior to others. With the lower estimate of the 95% credible interval (CrI) not exceeding the predefined threshold of 15%, evidence at 48 weeks supported the non-inferiority of ritonavir-boosted lopinavir plus raltegravir to regimens including ritonavir-boosted protease inhibitor plus two NRTIs with respect to viral suppression (odds ratio 1·09, 95% CrI 0·88-1·35). Estimated efficacy of ritonavir-boosted darunavir (800 mg once daily) was too imprecise to determine non-inferiority. Overall, regimens did not differ significantly with respect to continuations, AIDS-defining illnesses or WHO stage 3-4 disease, or mortality.

INTERPRETATION

With the exception of ritonavir-boosted lopinavir plus raltegravir, the evidence base is unable to provide strong support to alternative second-line options to ritonavir-boosted protease inhibitor plus two NRTIs, and thus more trials are warranted.

FUNDING

WHO.

The Effect of Gene Variants on Levonorgestrel Pharmacokinetics When Combined With Antiretroviral Therapy Containing Efavirenz or Nevirapine

Reduced levonorgestrel concentrations from the levonorgestrel contraceptive implant was previously seen when given concomitantly with efavirenz. We sought to assess whether single nucleotide polymorphisms (SNPs) in genes involved in efavirenz and nevirapine metabolism were linked to these changes in levonorgestrel concentration. SNPs in CYP2B6, CYP2A6, NR1I2, and NR1I3 were analyzed. Associations of participant demographics and genotype with levonorgestrel pharmacokinetics were evaluated in HIV-positive women using the levonorgestrel implant plus efavirenz- or nevirapine-based antiretroviral therapy (ART), in comparison to ART-naïve women using multivariate linear regression. Efavirenz group: CYP2B6 516G>T was associated with lower levonorgestrel log₁₀ C_max and log₁₀ AUC. CYP2B6 15582C>T was associated with lower log₁₀ AUC. Nevirapine group: CYP2B6 516G>T was associated with higher log₁₀ C_max and lower log₁₀ C_min . Pharmacogenetic variations influenced subdermal levonorgestrel pharmacokinetics in HIV-positive women, indicating that the magnitude of the interaction with non-nucleoside reverse transcriptase inhibitors (NNRTIs) is influenced by host genetics.

An intravaginal ring for real-time evaluation of adherence to therapy

Two recent Phase III clinical trials to investigate an intravaginal ring for preventing HIV infection demonstrated that adherence to prescribed device use was a primary driver of efficacy. Surrogate methods for determining adherence in the studies were limited in their inability to monitor temporal patterns of use and allow deconvolution of the effects of adherence and device efficacy on HIV infection rates. To address this issue, we have developed functionality in an intravaginal ring to continuously monitor when the device is being used and maintain a log of adherence that can be accessed by clinicians after it is removed. An electronic module fabricated with common, inexpensive electronic components was encapsulated in a silicone intravaginal ring. The device uses temperature as a surrogate measure of periods of device insertion and removal, and stores a record of the data for subsequent retrieval. The adherence-monitoring intravaginal ring accurately recorded the device status over 33 simulated IN-OUT cycles and more than 1000 measurement cycles in vitro. Following initial in vitro testing in a temperature-controlled chamber, the device was evaluated in vivo in sheep using a predetermined insertion/removal pattern to simulate intravaginal ring use. After insertion into the vaginal cavity of a sheep, the logged data correctly indicated the device status over 29 hours of continuous measurement including three cycles of insertion and removal. The device described here is a promising, low-cost method for real-time adherence assessment in clinical trials involving medicated intravaginal rings or other intravaginal devices.

Renal histoarchitectural changes in nevirapine therapy: possible role of kolaviron and vitamin C in an experimental animal model

BACKGROUND

There is paucity of literature regarding the nephrotoxicity of antiretroviral drugs and its interaction with plant-based adjuvants. This study investigates the attenuating effect of kolaviron in nevirapine-therapy on the histological structure of the kidneys of adult male Sprague-Dawley rats.

OBJECTIVE

To determine the attenuating influence of anti-oxidant status of kolaviron on the kidneys of experimental animals following nevirapine administration.

METHODS

Forty eight pathogen-free adult male Sprague-Dawley rats were used for this study. The animals were divided into 8 groups (A-H) with 6 animals in each group. Group A was given normal saline as the control; group B was given nevirapine; group C was given kolaviron; group D was given vitamin C; group E was given nevirapine and kolaviron; group F was given nevirapine and vitamin C; Group G was given nevirapine and kolaviron (kolaviron withdrawn after day 28) and group H was given corn oil. The experiment lasted 56 days after which the animals were sacrificed, blood samples were collected through cardiac puncture for serum analysis and the kidneys were harvested and prepared for H& E histological examination.

RESULTS

Nevirapine caused histoarchitectural damage in the glomerular apparatus with resultant increase in kidney/body weight ratio (p<0.001). Adjuvant treatment with kolaviron attenuated these nephrotoxic effects. Serum anti-oxidant enzyme (SOD and CAT) activities were significantly reduced in kolaviron and vitamin C treated animals, whereas in the nevirapine group these parameters were significantly elevated (P<0.05). However, co-administration of nevirapine and vitamin C did not improve the histoarchitecture of the kidney.

CONCLUSION

Adjuvant treatment with kolaviron (an anti-oxidant) for 56 days appears to attenuate the nephrotoxicity of nevirapine in this model.

MTN-017: A Rectal Phase 2 Extended Safety and Acceptability Study of Tenofovir Reduced-Glycerin 1% Gel

Background

Human immunodeficiency virus (HIV) disproportionately affects men who have sex with men (MSM) and transgender women (TGW). Safe and acceptable topical HIV prevention methods that target the rectum are needed.

Methods

MTN-017 was a phase 2, 3-period, randomized sequence, open-label, expanded safety and acceptability crossover study comparing rectally applied reduced-glycerin (RG) 1% tenofovir (TFV) and oral emtricitabine/TFV disoproxil fumarate (FTC/TDF). In each 8-week study period participants were randomized to RG-TFV rectal gel daily, or RG-TFV rectal gel before and after receptive anal intercourse (RAI; or at least twice weekly in the event of no RAI), or daily oral FTC/TDF.

Results

MSM and TGW (n = 195) were enrolled from 8 sites in the United States, Thailand, Peru, and South Africa with mean age of 31.1 years (range 18-64). There were no differences in ≥grade 2 adverse event rates between daily gel (incidence rate ratio [IRR], 1.09; P = .59) or RAI gel (IRR, 0.90; P = .51) compared to FTC/TDF. High adherence (≥80% of prescribed doses assessed by unused product return and Short Message System reports) was less likely in the daily gel regimen (odds ratio [OR], 0.35; P < .001), and participants reported less likelihood of future daily gel use for HIV protection compared to FTC/TDF (OR, 0.38; P < .001).

Conclusions

Rectal application of RG TFV gel was safe in MSM and TGW. Adherence and product use likelihood were similar for the intermittent gel and daily oral FTC/TDF regimens, but lower for the daily gel regimen.

Clinical Trials Registration

NCT01687218.

Multicompartmental Pharmacokinetic Model of Tenofovir Delivery to the Rectal Mucosa by an Enema

Rectal enemas that contain prophylactic levels of anti-HIV microbicides such as tenofovir have emerged as a promising dosage form to prevent sexually transmitted HIV infections. The enema vehicle is promising due to its likely ability to deliver a large amount of drug along the length of the rectal canal. Computational models of microbicide drug delivery by enemas can help their design process by determining key factors governing drug transport and, more specifically, the time history and degree of protection. They can also inform interpretations of experimental pharmacokinetic measures such as drug concentrations in biopsies. The present work begins rectal microbicide PK modeling, for enema vehicles. Results here show that a paramount factor in drug transport is the time of enema retention; direct connectivity between enema fluid and the fluid within rectal crypts is also important. Computations of the percentage of stromal volume protected by a single enema dose indicate that even with only a minute of enema retention, protection of 100% can be achieved after around 14 minutes post dose. Concentrations in biopsies are dependent on biopsy thickness; and control and/or knowledge of thickness could improve accuracy and decrease variability in biopsy measurements. Results here provide evidence that enemas are a promising dosage form for rectal microbicide delivery, and offer insights into their rational design.

Phase IIb trial of in vivo electroporation mediated dual-plasmid hepatitis B virus DNA vaccine in chronic hepatitis B patients under lamivudine therapy

AIM

To assess the efficacy and safety of in vivo electroporation (EP)-mediated dual-plasmid hepatitis B virus (HBV) DNA vaccine vs placebo for sequential combination therapy with lamivudine (LAM) in patients with chronic hepatitis B.

METHODS

Two hundred and twenty-five patients were randomized to receive either LAM + vaccine (vaccine group, n = 109) or LAM + placebo (control group, n = 116). LAM treatment lasted 72 wk. Patients received the DNA vaccine or placebo by intramuscular injection mediated by EP at weeks 12 (start of treatment with vaccine or placebo, SOT), 16, 24, and 36 (end of treatment with vaccine or placebo, EOT).

RESULTS

In the modified intent-to-treat population, more patients had a decrease in HBV DNA > 2 log₁₀ IU/mL in the vaccine group at week 12 after EOT compared with the control group. A trend toward a difference in the number of patients with undetectable HBV DNA at week 28 after EOT was obtained. Adverse events were similar. In the dynamic per-protocol set, which excluded adefovir (ADV) add-on cases at each time point instantly after ADV administration due to LAM antiviral failure, more patients had a decrease in HBV DNA > 2 log₁₀ IU/mL in the vaccine group at week 12 and 28 after EOT compared with the control group. More patients with undetectable HBV DNA at week 28 after EOT in the vaccine group were also observed. Among patients with a viral load < 1000 copies/mL at week 12, more patients achieved HBeAg seroconversion in the vaccine group than among controls at week 36 after EOT, as well as less virological breakthrough and YMDD mutations.

CONCLUSION

The primary endpoint was not achieved using the HBV DNA vaccine. The HBV DNA vaccine could only be beneficial in subjects that have achieved initial virological response under LAM chemotherapy.

Drug Resistance and Virological Failure among HIV-Infected Patients after a Decade of Antiretroviral Treatment Expansion in Eight Provinces of China

Background

China’s National Free Antiretroviral Treatment Program (NFATP) has substantially increased the survival rate since 2002. However, the emergence of HIV drug resistance (HIVDR) limits the durability and effectiveness of antiretroviral treatment (ART) in at risk patients.

Method

A cross-sectional survey was conducted among patients having received a median of 13.9 months of ART in eight provinces in China. Demographic and clinical information was collected, and venous blood was sampled for CD4 cell counts, measurement of the HIV viral load (VL), and HIV drug resistance (HIVDR) genotyping. Possible risk factors for HIVDR were analyzed by the logistic regression model.

Results

The study included 765 patients. Among them, 65 patients (8.5%) had virological failure (VLF) defined as ≥1,000 copies/ml. Among the individuals with VLF, 64 were successful genotyped, and of these, 33 had one or more HIVDR mutations. The prevalence of HIVDR mutations among patients receiving first-line ART was 4.3% (33/765). All of the patients with HIVDR mutations were resistant to non-nucleoside transcriptase inhibitors, 81.8% were resistant to nucleoside reverse transcriptase inhibitors, and only 3% had mutations that caused resistance to protease inhibitors. Having lower ratios of drug intake in the past month and dwelling in two southwestern provinces were factors independently associated with the emergence of HIVDR.

Conclusion

Most patients receiving first-line ART treatment achieved sound virological and immunological outcomes. However, poor adherence is still a key problem, which has led to the high rate of HIVDR. It was notable that the proportion of drug resistance widely varied among the provinces. More studies are needed to focus on adherence.

Safety and Efficacy of a Dapivirine Vaginal Ring for HIV Prevention in Women

BACKGROUND

The incidence of human immunodeficiency virus (HIV) infection remains high among women in sub-Saharan Africa. We evaluated the safety and efficacy of extended use of a vaginal ring containing dapivirine for the prevention of HIV infection in 1959 healthy, sexually active women, 18 to 45 years of age, from seven communities in South Africa and Uganda.

METHODS

In this randomized, double-blind, placebo-controlled, phase 3 trial, we randomly assigned participants in a 2:1 ratio to receive vaginal rings containing either 25 mg of dapivirine or placebo. Participants inserted the rings themselves every 4 weeks for up to 24 months. The primary efficacy end point was the rate of HIV type 1 (HIV-1) seroconversion.

RESULTS

A total of 77 participants in the dapivirine group underwent HIV-1 seroconversion during 1888 person-years of follow-up (4.1 seroconversions per 100 person-years), as compared with 56 in the placebo group who underwent HIV-1 seroconversion during 917 person-years of follow-up (6.1 seroconversions per 100 person-years). The incidence of HIV-1 infection was 31% lower in the dapivirine group than in the placebo group (hazard ratio, 0.69; 95% confidence interval [CI], 0.49 to 0.99; P=0.04). There was no significant difference in efficacy of the dapivirine ring among women older than 21 years of age (hazard ratio for infection, 0.63; 95% CI, 0.41 to 0.97) and those 21 years of age or younger (hazard ratio, 0.85; 95% CI, 0.45 to 1.60; P=0.43 for treatment-by-age interaction). Among participants with HIV-1 infection, nonnucleoside reverse-transcriptase inhibitor resistance mutations were detected in 14 of 77 participants in the dapivirine group (18.2%) and in 9 of 56 (16.1%) in the placebo group. Serious adverse events occurred more often in the dapivirine group (in 38 participants [2.9%]) than in the placebo group (in 6 [0.9%]). However, no clear pattern was identified.

CONCLUSIONS

Among women in sub-Saharan Africa, the dapivirine ring was not associated with any safety concerns and was associated with a rate of acquisition of HIV-1 infection that was lower than the rate with placebo. (Funded by the International Partnership for Microbicides; ClinicalTrials.gov number, NCT01539226 .).

Use of a Vaginal Ring Containing Dapivirine for HIV-1 Prevention in Women

BACKGROUND

Antiretroviral medications that are used as prophylaxis can prevent acquisition of human immunodeficiency virus type 1 (HIV-1) infection. However, in clinical trials among African women, the incidence of HIV-1 infection was not reduced, probably because of low adherence. Longer-acting methods of drug delivery, such as vaginal rings, may simplify use of antiretroviral medications and provide HIV-1 protection.

METHODS

We conducted a phase 3, randomized, double-blind, placebo-controlled trial of a monthly vaginal ring containing dapivirine, a non-nucleoside HIV-1 reverse-transcriptase inhibitor, involving women between the ages of 18 and 45 years in Malawi, South Africa, Uganda, and Zimbabwe.

RESULTS

Among the 2629 women who were enrolled, 168 HIV-1 infections occurred: 71 in the dapivirine group and 97 in the placebo group (incidence, 3.3 and 4.5 per 100 person-years, respectively). The incidence of HIV-1 infection in the dapivirine group was lower by 27% (95% confidence interval [CI], 1 to 46; P=0.046) than that in the placebo group. In an analysis that excluded data from two sites that had reduced rates of retention and adherence, the incidence of HIV-1 infection in the dapivirine group was lower by 37% (95% CI, 12 to 56; P=0.007) than that in the placebo group. In a post hoc analysis, higher rates of HIV-1 protection were observed among women over the age of 21 years (56%; 95% CI, 31 to 71; P<0.001) but not among those 21 years of age or younger (-27%; 95% CI, -133 to 31; P=0.45), a difference that was correlated with reduced adherence. The rates of adverse medical events and antiretroviral resistance among women who acquired HIV-1 infection were similar in the two groups.

CONCLUSIONS

A monthly vaginal ring containing dapivirine reduced the risk of HIV-1 infection among African women, with increased efficacy in subgroups with evidence of increased adherence. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT01617096 .).

[Lopinavir/ritonavir in human immunodeficiency virus-infected women]

There are clear sex-related biological differences between men and women. Diseases that affect the two sexes differently are studied separately. However, some diseases affect both men and women, but their incidence or outcome are clearly different. In human immunodeficiency virus infection, the potential differences in the effects of antiretroviral therapy are poorly characterized and few studies have been designed to elucidate these differences. Moreover, women are usually poorly represented in clinical trials of antiretroviral drugs.

[Positioning of lopinavir/ritonavir in antiretroviral treatment schemes]

Lopinavir/ritonavir (LPV/r) was approved for use in the treatment of human immunodeficiency virus (HIV) infection in 2001 and is the protease inhibitor that has been most widely studied in clinical trials. Despite the time interval since its approval, all the evidence accumulated in the last 14 years indicates that LPV/r continues to occupy an important position among antiretroviral drugs. Firstly, LPV/r plus 2 nucleoside/nucleotide analogs is still considered a good option for initial antiretroviral therapy (ART). Secondly, numerous studies have evaluated the efficacy and safety of new initial ART strategies based on LPV/r in dual therapy. The results obtained suggest that LPV/r plus lamivudine (3TC) or raltegravir can be as effective in initial ART as standard triple therapy and justify their consideration as alternative regimens in this scenario. Thirdly, LPV/r is a pioneer drug, as well as being the agent with the largest amount of evidence from clinical trials on simplification to monotherapy (LPV/r) or dual therapy (LPV/r + 3TC). Lastly, LPV/r is highly useful is special situations. It has a low risk of liver toxicity in patients with chronic liver disease, its use is preferred in the treatment of patients with HIV-2, and it is safe and effective in preventing vertical HIV transmission.

Interaction between Darunavir and Etravirine Is Partly Mediated by CYP3A5 Polymorphism

OBJECTIVES

To assess the impact of the loss-of-function CYP3A5*3 allele (rs776746, 6986A>G SNP) on darunavir (DRV) plasma concentrations.

METHODS

135 HIV-1 infected patients treated with DRV-based therapy were included in the study and plasma samples were obtained immediately before drug intake in order to determine DRV trough concentrations using an ultra performance liquid chromatography method (UPLC) with diode-array detection (DAD). Noteworthy is the fact that in 16 (11.9%) patients, etravirine (ETR) was combined with DRV. CYP3A5 genotypes were determined using real time PCR method (TaqMan® genotyping assay). The patients were then classified into CYP3A5 expressors (CYP3A5*1 allele carriers) and non-expressors (CYP3A5*3 homozygous). Subsequently, the association between DRV plasma trough concentration ([DRV]plasma) and CYP3A5 genotype-based expression status was analyzed.

RESULTS

45% of the patients were classified as CYP3A5 expressors. In the whole cohort, mean [DRV]plasma was not different between CYP3A5 expressors and non-expressors (1894ng/ml [CI95%: 1566-2290] versus 1737ng/ml [CI95%: 1468-2057], p = 0.43). However, in the subgroup of the 16 patients receiving DRV combined with ETR, a significantly lower [DRV]plasma was observed for CYP3A5 expressors when compared to non-expressors (1385ng/ml [CI95%:886.3-2165] versus 3141ng/ml [CI95%:2042-4831], p = 0.007).

CONCLUSIONS

Interaction between DRV and ETR is partly mediated by CYP3A5 polymorphism with lower DRV plasma trough concentrations in CYP3A5 expressors suggesting a specific ETR-driven CYP3A5 activation only in CYP3A5 expressors. Consequently, these patients might be more at risk of infra-therapeutic [DRV]plasma. This potentially important observation is a good illustration of a genotype-based drug interaction, which could also have considerable consequences if translated to other CYP3A5-metabolized drugs. Further investigations are thus needed to confirm this association and to explore its clinical impact, mainly in the African population among whom CYP3A5 expressors are more frequent, before recommending systematic CYP3A5 pre-emptive genotyping for DRV-ETR co-administration.

Dolutegravir Plus Two Nucleoside Reverse Transcriptase Inhibitors versus Efavirenz Plus Two Nucleoside Reverse Transcriptase Inhibitors As Initial Antiretroviral Therapy for People with HIV: A Systematic Review

Background

Dolutegravir (DTG) is a once-daily unboosted second-generation integrase-inhibitor that along with two nucleoside reverse transcriptase inhibitors is one of several regimens recommended by the United States, United Kingdom and European Union for first-line antiretroviral treatment of people with HIV infection. Our objective was to review the evidence for the efficacy and safety of DTG-based first-line regimens compared to efavirenz (EFV)-based regimens.

Methods

We conducted a systematic review. We comprehensively searched a range of databases as well as conference abstracts and a trials registry. We used Cochrane methods in screening and data collection and assessed each study’s risk of bias with the Cochrane tool. We meta-analyzed data using a fixed-effects model. We used GRADE to assess evidence quality.

Results

From 492 search results, we identified two randomized controlled trials, reported in five peer-reviewed articles and one conference abstract. One trial tested two DTG-based regimens (DTG + abacavir (ABC) + lamivudine (3TC) or DTG + tenofovir + emtricitabine) against an EFV-based regimen (EFV+ ABC+3TC). The other trial tested DTG+ABC+3TC against EFV+ABC+3TC. In meta-analysis, DTG-containing regimens were superior to EFV-containing regimens at 48 weeks and at 96 weeks (RR = 1.10, 95% CI 1.04–1.16; and RR = 1.12, 95% CI 1.04–1.21, respectively). In one trial, the DTG-containing regimen was superior at 144 weeks (RR = 1.13, 95% CI 1.02–1.24). DTG-containing regimens were superior in reducing treatment discontinuation compared to those containing EFV at 96 weeks and at 144 weeks (RR = 0.27, 95% CI 0.15–0.50; and RR = 0.28, 95% CI 0.16–0.48, respectively). Risk of serious adverse events was similar in each regimen at 96 weeks (RR = 1.15, 95% CI 0.80–1.63) and 144 weeks (RR = 0.93, 95% CI 0.68–1.29). Risk of bias was moderate overall, as was GRADE evidence quality.

Conclusions

DTG-based regimens should be considered in future World Health Organization guidelines for initial HIV treatment.

Long-Term Durability of Tenofovir-Based Antiretroviral Therapy in Relation to the Co-Administration of Other Drug Classes in Routine Clinical Practice

Background

In clinical trials, toxicity leading to tenofovir disoproxil fumarate (TDF) discontinuation is rare (3% by 2 years); however in clinical practice it seems to be higher, particularly when TDF is co-administered with ritonavir-boosted protease inhibitors (PI/r). Aims of this study were to assess the rate of TDF discontinuations in clinical practice and to identify factors associated with the risk of stopping TDF.

Methods

All antiretroviral treatment (ART)-naive patients initiating a TDF-based regimen were selected from the ICONA Foundation Study cohort. The primary outcome was TDF discontinuation regardless of the reason; secondary outcome measures were TDF discontinuation due to toxicity and selective TDF discontinuation (that is, TDF discontinuation or substitution, maintaining unchanged the remaining antiretroviral treatment).

Results

3,618 ART-naïve patients were included: 54% started a PI/r-based and 46% a NNRTI-based based regimen. Two-hundred-seventy-seven patients discontinued TDF and reintroduced ART within 30 days without TDF. The probability of TDF discontinuation regardless of the reason was of 7.4% (95%CI:6.4–8.5) by 2 years and 14.1% (95%CI:12.2–16.1) by 5 years. The 5-year KM estimates in the PI/r vs. NNRTI group were 20.4% vs. 7.6%, respectively (log-rank p = 0.0001), for the outcome of stopping regardless of the reason, and 10.7% vs. 4.7% (p = 0.0001) for discontinuation due to toxicity. PI/r use and lower eGFR were associated with an increased risk of discontinuing TDF.

Conclusion

In our cohort, the frequency of TDF discontinuations was higher than that observed in clinical trials. Co-administration of TDF with PI/r was associated with an increased rate of TDF discontinuations. Further studies are needed to clarify the mechanisms that might have led to this outcome.

Efavirenz versus boosted atazanavir-containing regimens and immunologic, virologic, and clinical outcomes: A prospective study of HIV-positive individuals

OBJECTIVE

To compare regimens consisting of either ritonavir-boosted atazanavir or efavirenz and a nucleoside reverse transcriptase inhibitor (NRTI) backbone with respect to clinical, immunologic, and virologic outcomes.

DESIGN

Prospective studies of human immunodeficiency virus (HIV)-infected individuals in Europe and the United States included in the HIV-CAUSAL Collaboration.

METHODS

HIV-positive, antiretroviral therapy-naive, and acquired immune deficiency syndrome (AIDS)-free individuals were followed from the time they started an atazanavir or efavirenz regimen. We estimated an analog of the "intention-to-treat" effect for efavirenz versus atazanavir regimens on clinical, immunologic, and virologic outcomes with adjustment via inverse probability weighting for time-varying covariates.

RESULTS

A total of 4301 individuals started an atazanavir regimen (83 deaths, 157 AIDS-defining illnesses or deaths) and 18,786 individuals started an efavirenz regimen (389 deaths, 825 AIDS-defining illnesses or deaths). During a median follow-up of 31 months, the hazard ratios (95% confidence intervals) were 0.98 (0.77, 1.24) for death and 1.09 (0.91, 1.30) for AIDS-defining illness or death comparing efavirenz with atazanavir regimens. The 5-year survival difference was 0.1% (95% confidence interval: -0.7%, 0.8%) and the AIDS-free survival difference was -0.3% (-1.2%, 0.6%). After 12 months, the mean change in CD4 cell count was 20.8 (95% confidence interval: 13.9, 27.8) cells/mm lower and the risk of virologic failure was 20% (14%, 26%) lower in the efavirenz regimens.

CONCLUSION

Our estimates are consistent with a smaller 12-month increase in CD4 cell count, and a smaller risk of virologic failure at 12 months for efavirenz compared with atazanavir regimens. No overall differences could be detected with respect to 5-year survival or AIDS-free survival.

BREATHER (PENTA 16) Trial Group. Weekends-off efavirenz-based antiretroviral therapy in HIV-infected children, adolescents, and young adults (BREATHER): a randomised, open-label, non-inferiority, phase 2/3 trial

BACKGROUND

For HIV-1-infected young people facing lifelong antiretroviral therapy (ART), short cycle therapy with long-acting drugs offers potential for drug-free weekends, less toxicity, and better quality-of-life. We aimed to compare short cycle therapy (5 days on, 2 days off ART) versus continuous therapy (continuous ART).

METHODS

In this open-label, non-inferiority trial (BREATHER), eligible participants were aged 8-24 years, were stable on first-line efavirenz with two nucleoside reverse transcriptase inhibitors, and had HIV-1 RNA viral load less than 50 copies per mL for 12 months or longer. Patients were randomly assigned (1:1) to remain on continuous therapy or change to short cycle therapy according to a computer-generated randomisation list, with permuted blocks of varying size, stratified by age and African versus non-African sites; the list was prepared by the trial statistician and randomisation was done via a web service accessed by site clinician or one of the three coordinating trials units. The primary outcome was the proportion of participants with confirmed viral load 50 copies per mL or higher at any time up to the 48 week assessment, estimated with the Kaplan-Meier method. The trial was powered to exclude a non-inferiority margin of 12%. Analyses were intention to treat. The trial was registered with EudraCT, number 2009-012947-40, ISRCTN, number 97755073, and CTA, number 27505/0005/001-0001.

FINDINGS

Between April 1, 2011, and June 28, 2013, 199 participants from 11 countries worldwide were randomly assigned, 99 to the short cycle therapy and 100 to continuous therapy, and were followed up until the last patient reached 48 weeks. 105 (53%) were men, median age was 14 years (IQR 12-18), and median CD4 cell count was 735 cells per μL (IQR 576-968). Six (6%) patients assigned to the short cycle therapy versus seven (7%) assigned to continuous therapy had confirmed viral load 50 copies per mL or higher (difference -1·2%, 90% CI -7·3 to 4·9, non-inferiority shown). 13 grade 3 or 4 events occurred in the short cycle therapy group and 14 in the continuous therapy group (p=0·89). Two ART-related adverse events (one gynaecomastia and one spontaneous abortion) occurred in the short cycle therapy group compared with 14 (p=0·02) in the continuous therapy group (five lipodystrophy, two gynaecomastia, one suicidal ideation, one dizziness, one headache and syncope, one spontaneous abortion, one neutropenia, and two raised transaminases).

INTERPRETATION

Non-inferiority of maintaining virological suppression in children, adolescents, and young adults was shown for short cycle therapy versus continous therapy at 48 weeks, with similar resistance and a better safety profile. This short cycle therapy strategy is a viable option for adherent HIV-infected young people who are stable on efavirenz-based ART.

FUNDING

UK National Institute for Health Research Health Technology Assessment; UK Medical Research Council; European Commission; PENTA Foundation; INSERM SC10-US19, France.

Efficient Inhibition of HIV Replication in the Gastrointestinal and Female Reproductive Tracts of Humanized BLT Mice by EFdA

Background

The nucleoside reverse transcriptase inhibitor (NRTI) 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) in preclinical development exhibits improved safety and antiviral activity profiles with minimal drug resistance compared to approved NRTIs. However, the systemic antiviral efficacy of EFdA has not been fully evaluated. In this study, we utilized bone marrow/liver/thymus (BLT) humanized mice to investigate the systemic effect of EFdA treatment on HIV replication and CD4+ T cell depletion in the peripheral blood (PB) and tissues. In particular, we performed a comprehensive analysis of the female reproductive tract (FRT) and gastrointestinal (GI) tract, major sites of transmission, viral replication, and CD4+ T cell depletion and where some current antiretroviral drugs have a sub-optimal effect.

Results

EFdA treatment resulted in reduction of HIV-RNA in PB to undetectable levels in the majority of treated mice by 3 weeks post-treatment. HIV-RNA levels in cervicovaginal lavage of EFdA-treated BLT mice also declined to undetectable levels demonstrating strong penetration of EFdA into the FRT. Our results also demonstrate a strong systemic suppression of HIV replication in all tissues analyzed. In particular, we observed more than a 2-log difference in HIV-RNA levels in the GI tract and FRT of EFdA-treated BLT mice compared to untreated HIV-infected control mice. In addition, HIV-RNA was also significantly lower in the lymph nodes, liver, lung, spleen of EFdA-treated BLT mice compared to untreated HIV-infected control mice. Furthermore, EFdA treatment prevented the depletion of CD4+ T cells in the PB, mucosal tissues and lymphoid tissues.

Conclusion

Our findings indicate that EFdA is highly effective in controlling viral replication and preserving CD4+ T cells in particular with high efficiency in the GI and FRT tract. Thus, EFdA represents a strong potential candidate for further development as a part of antiretroviral therapy regimens.

Dosing nucleoside reverse transcriptase inhibitors in adults receiving continuous veno-venous hemofiltration

BACKGROUND AND OBJECTIVE

Characteristics of nucleoside reverse transcriptase inhibitors (NRTIs) make the drug class susceptible to elimination via continuous veno-venous hemofiltration (CVVH), potentially leading to suboptimal drug concentrations if given at the recommended anephric doses during CVVH. The objective of this study was to formulate NRTI dosing recommendations for adults receiving CVVH.

METHODS

A mathematical formula that estimates the amount of drug likely to be removed during CVVH at various flow rates was used to calculate the supplemental NRTI dose required during CVVH.

RESULTS

A proposed table of dosing recommendations for NRTIs during CVVH is presented.

CONCLUSION

Clinicians should utilize these recommendations in the context of each individual patient, taking into consideration patient-specific factors and severity of illness. Future pharmacokinetic research correlating plasma and intracellular concentrations of NRTIs during CVVH is warranted to elucidate appropriate dosing.

Comparison of first antiretroviral treatment duration and outcome in HIV, HIV–HBV and HIV–HCV infection

Hepatitis C virus (HCV) and hepatitis B virus (HBV) co-infection may differentially influence HIV treatment duration and outcome. This was assessed at The Ottawa Hospital Immunodeficiency Clinic in first-time highly active antiretroviral therapy (HAART) recipients visited between January 2000 and December 2004. Of 968 patients, 526/700 (75%) HIV, 173/230 (75%) HIV–HCV and 30/38 (79%) HIV–HBV-infected patients initiated HAART. Co-infected patients stopped treatment sooner (HBV – 10 months, HCV – 9 months) than HIV mono-infected (17 months) ( P<0.001). Injection drug history predicted shorter treatment duration (odds ratio [OR]1.59, P<0.001). Use of non-nucleoside-reverse-transcriptase-inhibitor-containing HAART (OR 0.76, P<0.01) and low-dose ritonavir (<400 mg twice daily)-based HAART (OR 0.83, P = 0.06) predicted longer treatment duration. HCV co-infection did not predict duration of therapy (OR 1.19, P=0.19) once controlled for by these three variables. Poor adherence was a major explanation for eventual treatment interruption in those with HIV–HCV (22% versus 5% in HIV alone; P<0.001) as was substance abuse (7% versus < 1% in HIV; P<0.001). Metabolic complications resulted in HAART interruption in HIV mono-infection (8%) but not with HBV or HCV co-infection (both <1%; P<0.001). Antiretroviral selection is critical to the longevity of initially prescribed regimens, irrespective of viral hepatitis co-infection. Attention to this and strategies targeting substance abuse and adherence in HIV–HCV are predicted to increase the duration of HAART.

Estimated Glomerular Filtration Rate Trajectories in HIV-Infected Subjects Treated With Different Ritonavir-Boosted Protease Inhibitors and Tenofovir Disoproxil Fumarate or Abacavir

The aim of the study was to evaluate in human immunodeficiency virus (HIV)-infected patients estimated glomerular filtration rate (eGFR) trajectories during treatment with different protease inhibitors (PIs) or a non-nucleoside reverse transcriptase inhibitor (NNRTI) plus tenofovir (TDF) or abacavir (ABC) and lamivudine or emtricitabine (xTC).Retrospective study of patients followed at a single clinical center; all patients who started TDF or ABC for the first time with a NNRTI or lopinavir/r (LPV/r) or atazanavir/r (ATV/r) or darunavir/r (DRV/r), for whom at least 1 eGFR value before the start and during the studied treatment was known, were included in this analysis. eGFR was calculated by means of the CKD-EPI formula. Univariate and multivariate mixed linear model (MLM) was applied to estimate eGFR slope with the considered antiretroviral treatment.In the 1658 patients treated with TDF/xTC (aged 43 [37-48] years, with an eGFR of 105 [96; 113] mL/min/1.73 m, 80% males, 92% Caucasians, 10% coinfected with HCV, 4% with diabetes, 11% with hypertension, 38% naive for antiretroviral therapy (ART), 37% with HIV-RNA <50 copies/mL) the median follow-up was 2.5 (1.2-4.6) years. Their adjusted eGFR slopes (95% CI) were -1.26 (-1.58; -0.95), -0.43 (-1.20; +0.33), -0.86 (-1.28; -0.44), and -0.20 (-0.42; +0.02) mL/min/1.73 m per year in patients treated with ATV/r, DRV/r, LPV/r, and NNRTI, respectively. Patients receiving ATV/r or LPV/r had a greater adjusted decline in eGFR compared with those receiving NNRTIs (difference -1.06 [-1.44; -0.69] mL/min/1.73 m per year, P <0.001; and -0.66 [-1.13; -0.20] mL/min/1.73 m per year, P = 0.005, respectively); adjusted eGFR slopes were similar in patients receiving DRV/r and in those receiving NNRTIs. Patients receiving ATV/r had a greater adjusted eGFR decline than those treated with DRV/r (difference -0.83 [-1.65; -0.02] mL/min/1.73 m per year; P = 0.04), but not than those receiving LPV/r; no significant difference was observed in adjusted eGFR slopes between patients receiving DRV/r and those receiving LPV/r. In the 286 patients treated with ABC and lamivudine, eGFR slopes were similar, independent of the PI.In patients receiving TDF/xTC, eGFR trajectories were small for all regimens and declined less in patients receiving DRV/r or NNRTIs than in those treated with ATV/r or LPV/r.

Risk Factors for Incident Diabetes in a Cohort Taking First-Line Nonnucleoside Reverse Transcriptase Inhibitor-Based Antiretroviral Therapy

Efavirenz is the preferred nonnucleoside reverse transcriptase inhibitor (NNRTI) in first-line antiretroviral therapy (ART) regimens in low- and middle-income countries, where the prevalence of diabetes is increasing. Randomized control trials have shown mild increases in plasma glucose in participants in the efavirenz arms, but no association has been reported with overt diabetes. We explored the association between efavirenz exposure and incident diabetes in a large Southern African cohort commencing NNRTI-based first-line ART. Our cohort included HIV-infected adults starting NNRTI-based ART in a private sector HIV disease management program from January 2002 to December 2011. Incident diabetes was identified by the initiation of diabetes treatment. Patients with prevalent diabetes were excluded. We included 56,298 patients with 113,297 patient-years of follow-up (PYFU) on first-line ART. The crude incidence of diabetes was 13.24 per 1000 PYFU. Treatment with efavirenz rather than nevirapine was associated with increased risk of developing diabetes (hazard ratio 1.27 (95% confidence interval (CI): 1.10-1.46)) in a multivariate analysis adjusting for age, sex, body mass index, baseline CD4 count, viral load, NRTI backbone, and exposure to other diabetogenic medicines. Zidovudine and stavudine exposure were also associated with an increased risk of developing diabetes. We found that treatment with efavirenz, as well as stavudine and zidovudine, increased the risk of incident diabetes. Interventions to detect and prevent diabetes should be implemented in ART programs, and use of antiretrovirals with lower risk of metabolic complications should be encouraged.

Efficacy, safety, bone and metabolic effects of HIV nucleoside reverse transcriptase inhibitor BMS-986001 (AI467003): a phase 2b randomised, controlled, partly blinded trial

BACKGROUND

BMS-986001 is a thymidine analogue nucleoside reverse transcriptase inhibitor (NRTI) designed to maintain in-vitro antiviral activity while minimising off-target effects. We assessed the efficacy and safety of BMS-986001 versus tenofovir disoproxil fumarate in treatment-naive patients with HIV-1.

METHODS

In this phase 2b, randomised, active-controlled trial (AI467003), we recruited treatment-naive (no current or previous exposure to an antiretroviral drug for >1 week) adults (aged at least 18 years) with HIV-1 from 47 sites across Asia, Australia, Europe, North America, South Africa, and South America. Patients with plasma HIV-1 RNA greater than 5000 copies per mL and CD4 counts greater than 200 cells per μL were randomly assigned (2:2:2:3) to receive BMS-986001 100 mg, 200 mg, or 400 mg once a day or to receive tenofovir disoproxil fumarate 300 mg once a day; each allocation was given with efavirenz 600 mg once a day and lamivudine 300 mg once a day. Both patients and investigators were masked to BMS-986001 dose (achieved with similar looking placebo tablets), but not allocation up to and including week 48. The primary endpoints were the proportion of patients with plasma HIV-1 RNA less than 50 copies per mL and safety events (serious adverse events and adverse events leading to discontinuation) through week 24; the main analysis was with a modified intention-to-treat population. Resistance analysis was a secondary endpoint, and additional safety parameters were exploratory endpoints. This trial is registered with ClinicalTrials.gov, number NCT01489046, and the European Clinical Trials Database, number EudraCT 2011-003329-89.

FINDINGS

Patients were recruited between Jan 25, 2012, and Oct 3, 2012; 757 patients were assessed for eligibility and 301 were randomly assigned to receive either BMS-986001 once a day (67 patients to 100 mg, 67 to 200 mg, and 66 to 400 mg) or tenofovir disoproxil fumarate (n=101). 297 patients received at least one dose of study drug. At week 24, 57 (88%) of 65 patients for whom there were data in the 100 mg group, 54 (81%) of 67 in the 200 mg group, 62 (94%) of 66 in the 400 mg group achieved HIV-1 RNA less than 50 copies per mL, compared with 88 (89%) of 99 in the tenofovir disoproxil fumarate group (modified intention-to-treat population). BMS-986001 was generally well tolerated through week 48. Two patients had BMS-986001-related serious adverse events (atypical drug eruption and thrombocytopenia) and two in the tenofovir disoproxil fumarate group had study drug-related serious adverse events (potential drug-induced liver injury and depression or lipodystrophy) that led to discontinuation. NRTI resistance-associated mutations were reported in four (2%) of 198 patients, and non-NRTI mutations in 17 (9%) of 198 patients receiving BMS-986001 versus none of 99 and one (1%) of 99 patients receiving tenofovir disoproxil fumarate, respectively. Compared with tenofovir disoproxil fumarate, individuals in the BMS-986001 groups showed a smaller decrease in lumbar spine and hip bone mineral density but greater accumulation of limb and trunk fat, subcutaneous and visceral adipose tissue, and increased total cholesterol.

INTERPRETATION

BMS-986001 had similar efficacy to that of tenofovir disoproxil fumarate and was associated with a smaller decrease in bone mineral density; however, greater resistance and gains in both peripheral and central fat accumulation were recorded for the investigational drug. Bristol-Myers Squibb has discontinued its involvement in the development of BMS-986001, and future decisions on development will be made by Oncolys BioPharma.

FUNDING

Bristol-Myers Squibb.