SummaryBackgroundRandomised placebo-controlled trials have shown that daily oral pre-exposure prophylaxis (PrEP) with tenofovir–emtricitabine reduces the risk of HIV infection. However, this benefit could be counteracted by risk compensation in users of PrEP. We did the PROUD study to assess this effect.MethodsPROUD is an open-label randomised trial done at 13 sexual health clinics in England. We enrolled HIV-negative gay and other men who have sex with men who had had anal intercourse without a condom in the previous 90 days. Participants were randomly assigned (1:1) to receive daily combined tenofovir disoproxil fumarate (245 mg) and emtricitabine (200 mg) either immediately or after a deferral period of 1 year. Randomisation was done via web-based access to a central computer-generated list with variable block sizes (stratified by clinical site). Follow-up was quarterly. The primary outcomes for the pilot phase were time to accrue 500 participants and retention; secondary outcomes included incident HIV infection during the deferral period, safety, adherence, and risk compensation. The trial is registered with ISRCTN (number ISRCTN94465371) and ClinicalTrials.gov (NCT02065986).FindingsWe enrolled 544 participants (275 in the immediate group, 269 in the deferred group) between Nov 29, 2012, and April 30, 2014. Based on early evidence of effectiveness, the trial steering committee recommended on Oct 13, 2014, that all deferred participants be offered PrEP. Follow-up for HIV incidence was complete for 243 (94%) of 259 patient-years in the immediate group versus 222 (90%) of 245 patient-years in the deferred group. Three HIV infections occurred in the immediate group (1·2/100 person-years) versus 20 in the deferred group (9·0/100 person-years) despite 174 prescriptions of post-exposure prophylaxis in the deferred group (relative reduction 86%, 90% CI 64–96, p=0·0001; absolute difference 7·8/100 person-years, 90% CI 4·3–11·3). 13 men (90% CI 9–23) in a similar population would need access to 1 year of PrEP to avert one HIV infection. We recorded no serious adverse drug reactions; 28 adverse events, most commonly nausea, headache, and arthralgia, resulted in interruption of PrEp. We detected no difference in the occurrence of sexually transmitted infections, including rectal gonorrhoea and chlamydia, between groups, despite a suggestion of risk compensation among some PrEP recipients.InterpretationIn this high incidence population, daily tenofovir–emtricitabine conferred even higher protection against HIV than in placebo-controlled trials, refuting concerns that effectiveness would be less in a real-world setting. There was no evidence of an increase in other sexually transmitted infections. Our findings strongly support the addition of PrEP to the standard of prevention for men who have sex with men at risk of HIV infection.FundingMRC Clinical Trials Unit at UCL, Public Health England, and Gilead Sciences.
Key Points• The frequency of CD161 ϩϩ MAIT cells is dramatically decreased in the blood of HIVinfected patients, and they are nonrecoverable with HAART.• Gut sequestration and apoptosis in response to bacterial signals may, amongst others, be mechanisms that contribute to this. IntroductionThe natural course of human immunodeficiency virus type 1 (HIV-1) infection is associated with progressive immune dysfunction, perturbation of immune-cell subsets and increased opportunistic infections. In early disease, there is a dramatic loss of CD4 ϩ T cells from the gastrointestinal tract resulting in impaired mucosal immunity, reduced peripheral CD4 ϩ T-cell count, and increased systemic T-cell activation. [1][2][3][4] These factors contribute to an increased susceptibility to infection with specific organisms such as Mycobacterium tuberculosis and Candida albicans. [5][6][7] In addition, more recent evidence suggests an important role for the loss of CD8 ϩ T cells in susceptibility to bacterial pneumonia and all-cause mortality in HIV infection. 8 MAIT cells are a distinct subset of tissue-infiltrating lymphocytes with antibacterial functions that account for up to one-third of the CD8 ϩ T-cell population in the blood of healthy individuals. [9][10][11] MAIT cells are identified by expression of a semi-invariant T-cell receptor (TCR), iV␣7.2, 10,12,13 which recognizes ligands presented by MHC class I related (MR1) protein. 14 MR1 presentation occurs on dendritic cells, monocytes, and lung epithelial cells in response to bacterial pathogens. 9,10,12 MAIT cells are activated in vitro in an MR1-dependent fashion by a range of bacterial and fungal pathogens, including Escherichia coli, M tuberculosis, and C albicans, 9,10 and in mouse models have been shown to provide protection against bacterial infection. 10,15 In addition, MAIT cells have been shown to be lost from the blood and present in the lungs of patients with active tuberculosis, suggesting they may play an important role in host immunity to M tuberculosis. 9,10 Specific subsets of CD4 ϩ and CD8 ϩ T cells, termed Th17 and Tc17, are defined by their ability to produce IL17A and are important in the regulation of mucosal integrity and antibacterial immunity. [16][17][18][19][20] Early in HIV infection, Th17 cells are lost from the gastrointestinal tract, but may be restored through long-term highly active antiretroviral therapy (HAART) concurrent with a reduction in immune activation levels. 21 The loss of this IL17A and Submitted June 12, 2012; accepted November 26, 2012. Prepublished online as Blood First Edition paper, December 18, 2012; DOI 10.1182 DOI 10. /blood-2012 *C.C. and J.E.U. contributed equally to this work.The online version of this article contains a data supplement.The publication costs of this article were defrayed in part by page charge payment. Therefore, and solely to indicate this fact, this article is hereby marked ''advertisement'' in accordance with 18 USC section 1734. For personal use only. on May 7, 2018. by guest www.bloodjournal.org...
Background Data on vaccine immunogenicity against SARS-CoV-2 are needed for the 40 million people globally living with HIV who might have less functional immunity and more associated comorbidities than the general population. We aimed to explore safety and immunogenicity of the ChAdOx1 nCoV-19 (AZD1222) vaccine in people with HIV. Methods In this single-arm open-label vaccination substudy within the protocol of the larger phase 2/3 trial COV002, adults aged 18–55 years with HIV were enrolled at two HIV clinics in London, UK. Eligible participants were required to be on antiretroviral therapy (ART), with undetectable plasma HIV viral loads (<50 copies per mL), and CD4 counts of more than 350 cells per μL. A prime-boost regimen of ChAdOx1 nCoV-19, with two doses was given 4–6 weeks apart. The primary outcomes for this substudy were safety and reactogenicity of the vaccine, as determined by serious adverse events and solicited local and systemic reactions. Humoral responses were measured by anti-spike IgG ELISA and antibody-mediated live virus neutralisation. Cell-mediated immune responses were measured by ex-vivo IFN-γ enzyme-linked immunospot assay (ELISpot) and T-cell proliferation. All outcomes were compared with an HIV-uninfected group from the main COV002 study within the same age group and dosing strategy and are reported until day 56 after prime vaccination. Outcomes were analysed in all participants who received both doses and with available samples. The COV002 study is registered with ClinicalTrials.gov , NCT04400838 , and is ongoing. Findings Between Nov 5 and Nov 24, 2020, 54 participants with HIV (all male, median age 42·5 years [IQR 37·2–49·8]) were enrolled and received two doses of ChAdOx1 nCoV-19. Median CD4 count at enrolment was 694·0 cells per μL (IQR 573·5–859·5). No serious adverse events occurred. Local and systemic reactions occurring during the first 7 days after prime vaccination included pain at the injection site (26 [49%] of 53 participants with available data), fatigue (25 [47%]), headache (25 [47%]), malaise (18 [34%]), chills (12 [23%]), muscle ache (19 [36%]), joint pain (five [9%]), and nausea (four [8%]), the frequencies of which were similar to the HIV-negative participants. Anti-spike IgG responses by ELISA peaked at day 42 (median 1440 ELISA units [EUs; IQR 704–2728]; n=50) and were sustained until day 56 (median 941 EUs [531–1445]; n=49). We found no correlation between the magnitude of the anti-spike IgG response at day 56 and CD4 cell count (p=0·93) or age (p=0·48). ELISpot and T-cell proliferative responses peaked at day 14 and 28 after prime dose and were sustained to day 56. Compared with participants without HIV, we found no difference in magnitude or persistence of SARS-CoV-2 spike-specific humoral or cellular responses (p>0·05 for all analyses). Interpretation In this study of people with HIV, ChAdOx1 nCoV-19 was ...
The rate at which HIV-1 infected individuals progress to AIDS is highly variable and impacted by T cell immunity. CD8 T cell inhibitory molecules are up-regulated in HIV-1 infection and associate with immune dysfunction. We evaluated participants (n = 122) recruited to the SPARTAC randomised clinical trial to determine whether CD8 T cell exhaustion markers PD-1, Lag-3 and Tim-3 were associated with immune activation and disease progression. Expression of PD-1, Tim-3, Lag-3 and CD38 on CD8 T cells from the closest pre-therapy time-point to seroconversion was measured by flow cytometry, and correlated with surrogate markers of HIV-1 disease (HIV-1 plasma viral load (pVL) and CD4 T cell count) and the trial endpoint (time to CD4 count <350 cells/μl or initiation of antiretroviral therapy). To explore the functional significance of these markers, co-expression of Eomes, T-bet and CD39 was assessed. Expression of PD-1 on CD8 and CD38 CD8 T cells correlated with pVL and CD4 count at baseline, and predicted time to the trial endpoint. Lag-3 expression was associated with pVL but not CD4 count. For all exhaustion markers, expression of CD38 on CD8 T cells increased the strength of associations. In Cox models, progression to the trial endpoint was most marked for PD-1/CD38 co-expressing cells, with evidence for a stronger effect within 12 weeks from confirmed diagnosis of PHI. The effect of PD-1 and Lag-3 expression on CD8 T cells retained statistical significance in Cox proportional hazards models including antiretroviral therapy and CD4 count, but not pVL as co-variants. Expression of ‘exhaustion’ or ‘immune checkpoint’ markers in early HIV-1 infection is associated with clinical progression and is impacted by immune activation and the duration of infection. New markers to identify exhausted T cells and novel interventions to reverse exhaustion may inform the development of novel immunotherapeutic approaches.
Risk-reduction counselling is a standard preventive intervention, but behaviour change is difficult to sustain over the duration of HIV infection. However, primary HIV infection (PHI) is highly infectious and plays a key role in transmission -especially through dense sexual networks -but is short term, so even transient risk reduction can mitigate its high infectivity. Targeting behaviour-change interventions at recently infected individuals may be highly effective, particularly in higher risk groups. We explored the potential impact on HIV transmission-risk behaviour of PHI diagnosis in men who have sex with men (MSM). MethodsMSM with PHI were interviewed at diagnosis and after 3 months of follow-up about their sexual behaviour in the 12-week periods before and after diagnosis and standard counselling. ResultsA total of 98 of 104 eligible MSM (94%) participated in the study, with 100% follow-up. PHI was associated with high levels of recreational drug use, low levels of condom use, high numbers of sexual partners and a history of sex work. In the 12 weeks post-diagnosis, 76% of participants eliminated risk of onward transmission entirely and, overall, there was a significant reduction in transmission-risk behaviour, with patients reporting greater condom use and fewer sexual partners. Those with continued transmission-risk behaviour were more likely to have another sexually transmitted infection (STI), use ketamine and have more sexual partners at baseline. ConclusionsMost MSM recently diagnosed with PHI changed their behaviour to substantially reduce the risk of onward HIV transmission. Strategies are needed to (a) increase diagnoses of PHI to target prevention efforts effectively and (b) further reduce risk behaviours by targeting enhanced counselling to those most likely to continue with risk behaviours.
HLA class I tetramers have revolutionized the study of Ag-specific CD8+ T cell responses. Technical problems and the rarity of Ag-specific CD4+ Th cells have not allowed the potential of HLA class II tetramers to be fully realized. Here, we optimize HLA class II tetramer staining methods through the use of a comprehensive panel of HIV-, influenza-, CMV-, and tetanus toxoid-specific tetramers. We find rapid and efficient staining of DR1- and DR4-restricted CD4+ cell lines and clones and show that TCR internalization is not a requirement for immunological staining. We combine tetramer staining with magnetic bead enrichment to detect rare Ag-specific CD4+ T cells with frequencies as low as 1 in 250,000 (0.0004% of CD4+ cells) in human PBLs analyzed directly ex vivo. This ultrasensitive detection allowed phenotypic analysis of rare CD4+ T lymphocytes that had experienced diverse exposure to Ag during the course of viral infections. These cells would not be detectable with normal flow-cytometric techniques.
kill' strategy, for future trials significant enhancement of both 'kick' and 'kill' agents will be required. Research in context panel Evidence before this study This randomised clinical trial was designed to test the concept of 'kick and kill' as a strategy to achieve a cure for HIV infection. Prior to this study, there was evidence from in vitro and single arm clinical studies that the histone deacetylase inhibitor (HDACi) class of drugs could induce viral transcription from latently infected cells, potentially creating a target for the immune system. In conjunction with this 'kick' to the latent HIV reservoir there was evidence that T cell immunitywhich determines HIV disease progression-could be enhanced through vaccination-induced responses, providing the 'kill'. Although the strategy of 'kick and kill' looked promising, there had been no powered RCTs to test it. Added value of the study RIVER tested 'kick and kill' using the HDACi vorinostat as the 'kick' combined with a vaccine strategy targeting conserved regions of the HIV genome. The vaccine aimed to produce T cells to kill latently-infected cells in which viral transcription had been induced by the HDACi. RIVER showed that the intervention was safe, with outstanding adherence to the complex trial protocol by the participants. However, even though there was evidence for both increased histone acetylation and potent vaccine-induced T-cell responses, the intervention did not confer any additional benefit on any measures of the HIV reservoir compared with antiretroviral therapy alone. Implications of all the available evidence. RIVER was the first RCT in treated recent HIV infection, and was not able to show any impact of 'kick and kill' on the primary outcome measure, or any marker of the HIV reservoir size. This is consistent with other studies which had tested HDACi alone. We did not, however, stop antiretroviral therapy in the RIVER trial participants, and future studies may include a treatment interruption as a further measure of impact. Whilst the RIVER trial suggests that this specific 'kick and kill' approach may not be an effective approach towards achieving HIV cure, the overall principle can not yet be dismissed, as more potent future interventions may have a greater impact.
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