Emtricitabine and tenofovir alafenamide vs emtricitabine and tenofovir disoproxil fumarate for HIV pre-exposure prophylaxis (DISCOVER): primary results from a randomised, double-blind, multicentre, active-controlled, phase 3, non-inferiority trial.

BACKGROUND: Tenofovir alafenamide shows high antiviral efficacy and improved renal and bone safety compared with tenofovir disoproxil fumarate when used for HIV treatment. Here, we report primary results from a blinded phase 3 study evaluating the efficacy and safety of pre-exposure prophylaxis (PrEP) with emtricitabine and tenofovir alafenamide versus emtricitabine and tenofovir disoproxil fumarate for HIV prevention. METHODS: This study is an ongoing, randomised, double-blind, multicentre, active-controlled, phase 3, non-inferiority trial done at 94 community, public health, and hospital-associated clinics located in regions of Europe and North America, where there is a high incidence of HIV or prevalence of people living with HIV, or both. We enrolled adult cisgender men who have sex with men and transgender women who have sex with men, both with a high risk of acquiring HIV on the basis of their self-reported sexual behaviour in the past 12 weeks or their recent history (within 24 weeks of enrolment) of bacterial sexually transmitted infections. Participants with current or previous use of PrEP with emtricitabine and tenofovir disoproxil fumarate were not excluded. We used a computer-generated random allocation sequence to randomly assign (1:1) participants to receive either emtricitabine (200 mg) and tenofovir alafenamide (25 mg) tablets daily, with matched placebo tablets (emtricitabine and tenofovir alafenamide group), or emtricitabine (200 mg) and tenofovir disoproxil fumarate (300 mg) tablets daily, with matched placebo tablets (emtricitabine and tenofovir disoproxil fumarate group). As such, all participants were given two tablets. The trial sponsor, investigators, participants, and the study staff who provided the study drugs, assessed the outcomes, and collected the data were masked to group assignment. The primary efficacy outcome was incident HIV infection, which was assessed when all participants had completed 48 weeks of follow-up and half of all participants had completed 96 weeks of follow-up. This full analysis set included all randomly assigned participants who had received at least one dose of the assigned study drug and had at least one post-baseline HIV test. Non-inferiority of emtricitabine and tenofovir alafenamide to emtricitabine and tenofovir disoproxil fumarate was established if the upper bound of the 95·003% CI of the HIV incidence rate ratio (IRR) was less than the prespecified non-inferiority margin of 1·62. We prespecified six secondary bone mineral density and renal biomarker safety endpoints to evaluate using the safety analysis set. This analysis set included all randomly assigned participants who had received at least one dose of the assigned study drug. This trial is registered with ClinicalTrials.gov, NCT02842086, and is no longer recruiting. FINDINGS: Between Sept 13, 2016, and June 30, 2017, 5387 (92%) of 5857 participants were randomly assigned and received emtricitabine and tenofovir alafenamide (n=2694) or emtricitabine and tenofovir disoproxil fumarate (n=2693). At the time of the primary efficacy analysis (ie, when all participants had completed 48 weeks and 50% had completed 96 weeks) emtricitabine and tenofovir alafenamide was non-inferior to emtricitabine and tenofovir disoproxil fumarate for HIV prevention, as the upper limit of the 95% CI of the IRR, was less than the prespecified non-inferiority margin of 1·62 (IRR 0·47 [95% CI 0·19-1·15]). After 8756 person-years of follow-up, 22 participants were diagnosed with HIV, seven participants in the emtricitabine and tenofovir alafenamide group (0·16 infections per 100 person-years [95% CI 0·06-0·33]), and 15 participants in the emtricitabine and tenofovir disoproxil fumarate group (0·34 infections per 100 person-years [0·19-0·56]). Both regimens were well tolerated, with a low number of participants reporting adverse events that led to discontinuation of the study drug (36 [1%] of 2694 participants in the emtricitabine and tenofovir alafenamide group vs 49 [2%] of 2693 participants in the emtricitabine and tenofovir disoproxil fumarate group). Emtricitabine and tenofovir alafenamide was superior to emtricitabine and tenofovir disoproxil fumarate in all six prespecified bone mineral density and renal biomarker safety endpoints. INTERPRETATION: Daily emtricitabine and tenofovir alafenamide shows non-inferior efficacy to daily emtricitabine and tenofovir disoproxil fumarate for HIV prevention, and the number of adverse events for both regimens was low. Emtricitabine and tenofovir alafenamide had more favourable effects on bone mineral density and biomarkers of renal safety than emtricitabine and tenofovir disoproxil fumarate. FUNDING: Gilead Sciences.

Shift in monocyte apoptosis with increasing viral load and change in apoptosis-related ISG/Bcl2 family gene expression in chronically HIV-1-infected subjects.

UNLABELLED: Although monocytes and macrophages are targets of HIV-1-mediated immunopathology, the impact of high viremia on activation-induced monocyte apoptosis relative to monocyte and macrophage activation changes remains undetermined. In this study, we determined constitutive and oxidative stress-induced monocyte apoptosis in uninfected and HIV(+) individuals across a spectrum of viral loads (n = 35; range, 2,243 to 1,355,998 HIV-1 RNA copies/ml) and CD4 counts (range, 26 to 801 cells/mm(3)). Both constitutive apoptosis and oxidative stress-induced apoptosis were positively associated with viral load and negatively associated with CD4, with an elevation in apoptosis occurring in patients with more than 40,000 (4.6 log) copies/ml. As expected, expression of Rb1 and interferon-stimulated genes (ISGs), plasma soluble CD163 (sCD163) concentration, and the proportion of CD14(++) CD16(+) intermediate monocytes were elevated in viremic patients compared to those in uninfected controls. Although CD14(++) CD16(+) frequencies, sCD14, sCD163, and most ISG expression were not directly associated with a change in apoptosis, sCD14 and ISG expression showed an association with increasing viral load. Multivariable analysis of clinical values and monocyte gene expression identified changes in IFI27, IFITM2, Rb1, and Bcl2 expression as determinants of constitutive apoptosis (P = 3.77 × 10(-5); adjusted R(2) = 0.5983), while changes in viral load, IFITM2, Rb1, and Bax expression were determinants of oxidative stress-induced apoptosis (P = 5.59 × 10(-5); adjusted R(2) = 0.5996). Our data demonstrate differential activation states in monocytes between levels of viremia in association with differences in apoptosis that may contribute to greater monocyte turnover with high viremia. IMPORTANCE: This study characterized differential monocyte activation, apoptosis, and apoptosis-related gene expression in low- versus high-level viremic HIV-1 patients, suggesting a shift in apoptosis regulation that may be associated with disease state. Using single and multivariable analysis of monocyte activation parameters and gene expression, we supported the hypothesis that monocyte apoptosis in HIV disease is a reflection of viremia and activation state with contributions from gene expression changes within the ISG and Bcl2 gene families. Understanding monocyte apoptosis response may inform HIV immunopathogenesis, retention of infected macrophages, and monocyte turnover in low- or high-viral-load states.

Weight gain before and after switch from TDF to TAF in a U.S. cohort study.

INTRODUCTION: Although weight gain has been reported with the use of integrase strand transfer inhibitors (InSTI), concurrent use of tenofovir alafenamide (TAF) has been implicated in recent studies. This study examined weight changes in people living with HIV (PLWH) who switched from tenofovir disoproxil fumarate (TDF) to TAF, to clarify the relative contribution to weight gain of core agents versus TDF to TAF switch. METHODS: Antiretroviral-experienced, virologically suppressed PLWH in the U.S. OPERA cohort were included if they switched from TDF to TAF (5NOV2015-28FEB2019) and either maintained all other antiretrovirals or switched from a non-InSTI to an InSTI. Linear mixed models were used to assess weight changes before/after the switch to TAF (restricted cubic splines on time) and rates of change over time (linear splines on time, based on the shape of the weight change curves). Changes in weight on TDF or TAF were assessed among those who maintained other antiretrovirals (overall, by core class), and those who maintained an InSTI or switched to an InSTI (by core agent). All models were adjusted for age, sex, race, (age-sex, race-sex interactions), BMI, CD4 cell count, endocrine disorders and concurrent medications that could affect weight. RESULTS: A total of 6908 PLWH were included, with 5479 maintaining all other antiretrovirals (boosted protease inhibitor: 746, non-nucleoside reverse transcriptase inhibitor: 1452, InSTI: 3281) and 1429 switching from a non-InSTI to an InSTI (elvitegravir/cobicistat: 1120, dolutegravir: 174, bictegravir: 129). In adjusted models, modest weight gain was observed over time on TDF for most (0.24 to 0.71 kg/year); raltegravir was the exception with weight loss. Switching to TAF was associated with early, pronounced weight gain for all (1.80 to 4.47 kg/year). This effect with TAF switch was observed both in PLWH maintaining other antiretrovirals and those switching to an InSTI, regardless of which InSTI agent was used. Weight gain tended to slow down or plateau approximately nine months after switch to TAF. CONCLUSIONS: In this large, diverse U.S. cohort of PLWH, switching from TDF to TAF was associated with pronounced weight gain immediately after switch, regardless of the core class or core agent, suggesting an independent effect of TAF on weight gain.

Are We Hitting the Target? HIV Pre-Exposure Prophylaxis from 2012 to 2020 in the OPERA Cohort.

Preventing HIV transmission is a crucial step in ending the HIV epidemic. Safe and effective pre-exposure prophylaxis (PrEP) has been available in the United States since 2012. We set out to determine if persons at greatest risk for HIV acquisition were receiving HIV PrEP. HIV-negative individuals from the Observational Pharmaco-Epidemiology Research & Analysis (OPERA) cohort who were prescribed daily PrEP were contrasted with newly diagnosed HIV persons without PrEP use between July 16, 2012 and October 31, 2020 to determine if the PrEP prescriptions reached the populations who were seroconverting. Poisson regression was used to estimate incidence rates of seroconversion to HIV among PrEP initiators, as well as new diagnoses of sexually transmitted infections among both the PrEP group and the newly HIV+ group. Out of the 14,598 PrEP users and 3558 persons newly diagnosed with HIV in OPERA, demographics varied widely. Older individuals, those of non-Black race, men, nonintravenous (IV) drug users, and those with commercial insurance were proportionally overrepresented among those prescribed PrEP compared to persons newly diagnosed with HIV during the same time period. Over 82% of new HIV+ individuals received care in the southern United States compared to only 45% of PrEP users. Seroconversion to HIV among PrEP users was generally uncommon, although more frequent among those who identified as Black individuals, especially in the 13-25 years old age range. In conclusion, providers need innovative programs to better identify, educate, and link those at greatest risk of HIV acquisition, especially young people, women, Black individuals, and IV drug users, to PrEP.

Abacavir Hypersensitivity Reaction Reporting Rates During a Decade of HLA-B*5701 Screening as a Risk-Mitigation Measure.

INTRODUCTION: Human leukocyte antigen (HLA)-B*5701 screening identifies patients at increased risk for abacavir (ABC) hypersensitivity reaction (HSR). Screening was adopted in GlaxoSmithKline and ViiV Healthcare clinical trials in 2007 and human immunodeficiency virus treatment guidelines in 2008. Company meta-analyses of trials pre-HLA-B*5701 screening reported HSR rates of 4-8%. We analyzed the effectiveness of HLA-B*5701 screening on reducing HSR rates using clinical trial, Observational Pharmaco-Epidemiology Research & Analysis (OPERA) cohort, and spontaneous reporting data. METHODS: A meta-analysis examined 12 trials in 3063 HLA-B*5701-negative patients receiving an ABC-containing regimen from April 9, 2007, to September 22, 2015. Potential cases were identified using prespecified Medical Dictionary for Regulatory Activities (MedDRA) preferred terms (drug hypersensitivity, hypersensitivity, anaphylactic reaction, anaphylaxis) and adjudicated against a Company ABC HSR case definition. Investigator-diagnosed cases were identified and rates were calculated. In the OPERA cohort, 9619 patients initiating their first ABC-containing regimen from January 1, 1999, to January 1, 2016, were identified. Patients were observed from regimen start until the earliest-following censoring event: ABC discontinuation, loss to follow-up, death, or study end (July 31, 2016). OPERA physicians evaluated events against OPERA definitions for definite/probable cases of ABC HSR; rates were calculated pre- and post-2008. The Company case definition was used to identify spontaneously reported cases for four marketed ABC-containing products; reporting rates were calculated using estimated exposure from sales data, through December 31, 2016. RESULTS: Suspected ABC HSR rates were 1.3% or less in the meta-analysis. In the OPERA cohort, the rate was 0.4% among patients initiating ABC post-2008 versus 1.3% pre-2008 (p<0.0001). Spontaneous reporting rates were low post-2008 (54 to 22 cases per 100,000 patient-years exposure [PYE]) versus pre-2008 (618 to 55 cases per 100,000 PYE). CONCLUSIONS: Clinically suspected ABC HSR rates were 1.3% or less in HLA-B*5701-negative patients. Recognizing their limitations, data from the OPERA cohort and spontaneous reporting indicate that HLA-B*5701 screening has reduced reporting rates of suspected HSR in clinical practice. Where screening for HLA-B*5701 is standard care, patients should be confirmed negative for this allele before starting ABC treatment.

A correlate of HIV-1 control consisting of both innate and adaptive immune parameters best predicts viral load by multivariable analysis in HIV-1 infected viremic controllers and chronically-infected non-controllers.

HIV-1 infected viremic controllers maintain durable viral suppression below 2000 copies viral RNA/ml without anti-retroviral therapy (ART), and the immunological factor(s) associated with host control in presence of low but detectable viral replication are of considerable interest. Here, we utilized a multivariable analysis to identify which innate and adaptive immune parameters best correlated with viral control utilizing a cohort of viremic controllers (median 704 viral RNA/ml) and non-controllers (median 21,932 viral RNA/ml) that were matched for similar CD4+ T cell counts in the absence of ART. We observed that HIV-1 Gag-specific CD8+ T cell responses were preferentially targeted over Pol-specific responses in viremic controllers (p = 0.0137), while Pol-specific responses were positively associated with viral load (rho = 0.7753, p = 0.0001, n = 23). Viremic controllers exhibited significantly higher NK and plasmacytoid dendritic cells (pDC) frequency as well as retained expression of the NK CD16 receptor and strong target cell-induced NK cell IFN-gamma production compared to non-controllers (p<0.05). Despite differences in innate and adaptive immune function however, both viremic controllers (p<0.05) and non-controller subjects (p<0.001) exhibited significantly increased CD8+ T cell activation and spontaneous NK cell degranulation compared to uninfected donors. Overall, we identified that a combination of innate (pDC frequency) and adaptive (Pol-specific CD8+ T cell responses) immune parameters best predicted viral load (R2 = 0.5864, p = 0.0021, n = 17) by a multivariable analysis. Together, this data indicates that preferential Gag-specific over Pol-specific CD8+ T cell responses along with a retention of functional innate subsets best predict host control over viral replication in HIV-1 infected viremic controllers compared to chronically-infected non-controllers.

Increased plasmacytoid dendritic cell maturation and natural killer cell activation in HIV-1 exposed, uninfected intravenous drug users.

BACKGROUND: Increased natural killer (NK) activation has been associated with resistance to HIV-1 infection in several cohorts of HIV-1 exposed, uninfected individuals. Inheritance of protective NK receptor alleles (KIR3DS1 and KIR3DL1) has also been observed in a subset of HIV-1 exposed, uninfected individuals. However, the exact mechanism contributing to NK activation in HIV-1 exposed, uninfected intravenous drug users (EU-IDU) remains to be elucidated. OBJECTIVE: We investigated the role of both host genotype and pathogen-induced dendritic cell modulation of NK activation during high-risk activity in a cohort of 15 EU-IDU individuals and 15 control, uninfected donors from Philadelphia. DESIGN: We assessed the activation status of NK cells and dendritic cells by flow cytometry and utilized functional assays of NK-DC cross-talk to characterize the innate immune compartment in EU-IDU individuals. RESULTS: As previously reported, NK cell activation (CD69) and/or degranulation (CD107a) was significantly increased in EU-IDU individuals compared with control uninfected donors (P = 0.0056, n = 13). Genotypic analysis indicated that the frequency of protective KIR (KIR3DS1) and HLA-Bw4*80I ligands was not enriched in our cohort of EU-IDU individuals. Rather, plasmacytoid dendritic cells (PDC) from EU-IDU exhibited heightened maturation (CD83) compared with control uninfected donors (P = 0.0011, n = 12). When stimulated in vitro, both PDCs and NK cells from EU-IDU individuals maintained strong effector cell function and did not exhibit signs of exhaustion. CONCLUSION: Increased maturation of PDCs is associated with heightened NK activation in EU-IDU individuals suggesting that both members of the innate compartment may contribute to resistance from HIV-1 infection in EU-IDU.

Delayed loss of control of plasma lipopolysaccharide levels after therapy interruption in chronically HIV-1-infected patients.

OBJECTIVE: Increased circulating levels of lipopolysaccharide (LPS) have been demonstrated in HIV-1-infected progressors. We investigated the effect of antiretroviral therapy (ART) interruptions on plasma LPS levels. DESIGN AND METHODS: Overall, 77 individuals participated in this study (51 HIV-positive and 26 healthy). Ten out of 51 HIV-positive participants were viremic ART-naive patients and 41 out of 51 were chronically suppressed patients on ART (three or more drugs, CD4 cell count more than 400 cells/microl, HIV-1 RNA less than 500 copies/ml for more than 8 months, less than 50 copies/ml at recruitment) undergoing therapy interruption. The limulus amebocyte assay was used to measure plasma LPS levels; enzyme-linked immunosorbent assay to measure plasma levels of endotoxin-core antibodies (EndoCAb), soluble (s)CD14, LPS-binding protein and IFN-alpha; immunoblotting to measure plasma gelsolin levels; and same day whole blood flow cytometry to measure levels of T-cell-activation markers (CD8/CD38, CD8/HLA-DR and CD3/CD95). RESULTS: Increases in viremia and T-cell-activation markers were observed during therapy interruptions. During short-term therapy interruptions of less than 12 weeks, no change in LPS levels was found, whereas negative associations between viral load and LPS levels (Spearman's Rho = -0.612, P = 0.0152), viral load and EndoCAb change (DeltaEndoCAb, correlation = -0.502, P = 0.0204), and between DeltaLPS and DeltaEndoCAb (correlation = -0.851, P = 0.0073) were observed. In contrast, increased LPS (P = 0.0171) and sCD14 (P < 0.0001) levels were observed during long-term therapy interruption of more than 12 weeks compared with levels during ART, together with no association between LPS and viral load or EndoCAb. No association between immune activation and LPS was evident at any time point. CONCLUSION: Increased plasma LPS levels were observed only after more than 12 weeks of ART interruption, despite presence of LPS-controlling host mechanisms.

Antiretroviral therapy in HIV-infected patients with multidrug-resistant virus: applying the guidelines to practice.

Abstract Current treatment guidelines recommend maintenance of HIV-1 viral load below detectable levels (<50 copies per milliliter), even in extensively treated patients with multidrug-resistant HIV-1. Given recent advances in drug development and the availability of new agents with activity against antiretroviral-resistant HIV-1 viral strains, this goal is increasingly attainable for treatment-experienced patients. A stepwise approach to management of patients harboring antiretroviral-resistant HIV is presented, including assessment of adherence, a description of the use of resistance testing and utilization of new antiretroviral agents.

Increased mitochondrial mass characterizes the survival defect of HIV-specific CD8(+) T cells.

What governs the increased apoptosis sensitivity of HIV-specific CD8(+) T cells is poorly understood. Here, we examined the involvement of mitochondria in this apoptosis. Remarkably higher mitochondrial mass (MM) was found in HIV-specific compared with CMV-specific CD8(+) T cells from HIV(+) patients and this could not be attributed to their different differentiation status. MM(High) phenotype characterized those CD8(+) T cells from HIV(+) patients that are sensitive to spontaneous and CD95/Fas-induced apoptosis. CD38 expression did not correlate with high MM, whereas Bcl-2 levels were significantly reduced in both CD38(+) and CD38(-) HIV-specific CD8(+) T cells. Although CD38(+) HIV-specific CD8(+) T cells were more susceptible to apoptosis, CD38 expression does not explain on its own the selective apoptosis sensitivity of HIV-specific CD8(+) T cells, as CD38(-) HIV-specific CD8(+) T cells were more apoptotic than CD38(+) CMV-specific ones. Proapoptotic HIV-specific CD8(+) T cells were CD38(+)Bcl-2(Low)MM(High). Copolarization of mitochondria with CD95/Fas capping, very early in CD95/Fas-induced apoptosis of HIV-specific CD8(+) T cells, suggests that mitochondria act as an amplification step for this apoptosis. Thus, an extensive mitochondrial network contributes to apoptosis sensitivity of CD8(+) T cells and, when this occurs together with reduced levels of Bcl-2 and chronic activation, determines the proapoptotic state of HIV-specific CD8(+) T cells.

Actin integrity is indispensable for CD95/Fas-induced apoptosis of HIV-specific CD8+ T cells.

We have recently provided data suggesting a potential role for mitochondria and Bcl-2-family molecules in apoptosis sensitivity of HIV-specific CD8+ T cells. Here, we report on the role of filamentous (F) actin in this process. Disruption of actin by cytochalasin D (cytD) or lantrunculin A remarkably reduced CD95/Fas-induced apoptosis of HIV-specific CD8+ T cells while their spontaneous apoptosis was unaffected. This inhibition cannot be attributed to changes of CD95/Fas distribution or levels in these cells. Furthermore, cytD treatment reduced CD95/Fas-induced apoptosis of CD8+ T cells from HIV+ patients independently of their differentiation status. CD95/Fas-induced apoptosis of both CD38+ and CD38- HIV-specific CD8+ T cells was inhibited by cytD treatment indicating that actin mediates this apoptotic process independently of the activation level of these cells. CytD was found to reduce the activation of caspase-8 induced by short treatment of purified CD8+ T cells from HIV+ patients with anti-CD95/Fas. Our data reveal actin as a critical mediator of HIV-specific CD8+ T cell apoptosis; further analysis of the molecular mechanisms governing this process may potentially contribute to design new therapies targeting the enhancement of the immune system in HIV infection.

HIV-specific CD8+ T cells exhibit markedly reduced levels of Bcl-2 and Bcl-xL.

Human immunodeficiency virus-specific CD8(+) T cells are highly sensitive to spontaneous and CD95/Fas-induced apoptosis, and this sensitivity may impair their ability to control HIV infection. To elucidate the mechanism behind this sensitivity, in this study we examined the levels of antiapoptotic molecules Bcl-2 and Bcl-x(L) in HIV-specific CD8(+) T cells from HIV-infected individuals. Bcl-2 expression was markedly decreased in HIV-specific CD8(+) T cells compared with CMV-specific and total CD8(+) T cells from HIV-infected individuals as well as total CD8(+) T cells from healthy donors. CD8(+) T cell Bcl-2 levels inversely correlated with spontaneous and CD95/Fas-induced apoptosis of CD8(+) T cells from HIV-infected individuals. HIV-specific CD8(+) T cells also had significantly lower levels of Bcl-x(L) compared with CMV-specific CD8(+) T cells. Finally, IL-15 induces both Bcl-2 and Bcl-x(L) expression in HIV-specific and total CD8(+) T cells, and this correlated with apoptosis inhibition and increased survival in both short- and long-term cultures. Our data indicate that reduced Bcl-2 and Bcl-x(L) may play an important role in the increased sensitivity to apoptosis of HIV-specific CD8(+) T cells and suggest a possible mechanism by which IL-15 increases their survival.