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The progressive loss of CD4+ T cell population is the hallmark of HIV-1 infection but the mechanism underlying the slow T cell decline remains unclear. Some recent studies suggested that pyroptosis, a form of programmed cell death triggered during abortive HIV infection, is associated with the release of inflammatory cytokines, which can attract more CD4+ T cells to be infected. In this paper, we developed mathematical models to study whether this mechanism can explain the time scale of CD4+ T cell decline during HIV infection. Simulations of the models showed that cytokine induced T cell movement can explain the very slow decline of CD4+ T cells within untreated patients. The long-term CD4+ T cell dynamics predicted by the models were shown to be consistent with available data from patients in Rio de Janeiro, Brazil. Highly active antiretroviral therapy has the potential to restore the CD4+ T cell population but CD4+ response depends on the effectiveness of the therapy, when the therapy is initiated, and whether there are drug sanctuary sites. The model also showed that chronic inflammation induced by pyroptosis may facilitate persistence of the HIV latent reservoir by promoting homeostatic proliferation of memory CD4+ cells. These results improve our understanding of the long-term T cell dynamics in HIV-1 infection, and support that new treatment strategies, such as the use of caspase-1 inhibitors that inhibit pyroptosis, may maintain the CD4+ T cell population and reduce the latent reservoir size.

HIV-infected drug users have increased age-matched morbidity and mortality compared with HIV-infected people who do not use drugs. Substance-use disorders negatively affect the health of HIV-infected drug users, who also have frequent medical and psychiatric comorbidities that complicate HIV treatment and prevention. Evidence-based treatments are available for the management of substance-use disorders, mental illness, HIV and other infectious complications such as viral hepatitis and tuberculosis, and many non-HIV-associated comorbidities. Tuberculosis co-infection in HIV-infected drug users, including disease caused by drug-resistant strains, is acquired and transmitted as a consequence of inadequate prescription of antiretroviral therapy, poor adherence, and repeated interfaces with congregate settings such as prisons. Medication-assisted therapies provide the strongest evidence for HIV treatment and prevention efforts, yet are often not available where they are needed most. Antiretroviral therapy, when prescribed and adherence is at an optimum, improves health-related outcomes for HIV infection and many of its comorbidities, including tuberculosis, viral hepatitis, and renal and cardiovascular disease. Simultaneous clinical management of multiple comorbidities in HIV-infected drug users might result in complex pharmacokinetic drug interactions that must be adequately addressed. Moreover, interventions to improve adherence to treatment, including integration of health services delivery, are needed. Multifaceted, interdisciplinary approaches are urgently needed to achieve parity in health outcomes in HIV-infected drug users.

The effect of HIV pre-exposure prophylaxis (PrEP) depends on uptake, adherence, and sexual practices. We aimed to assess these factors in a cohort of HIV-negative people at risk of infection. In our cohort study, men and transgender women who have sex with men previously enrolled in PrEP trials (ATN 082, iPrEx, and US Safety Study) were enrolled in a 72 week open-label extension. We measured drug concentrations in plasma and dried blood spots in seroconverters and a random sample of seronegative participants. We assessed PrEP uptake, adherence, sexual practices, and HIV incidence. Statistical methods included Poisson models, comparison of proportions, and generalised estimating equations. We enrolled 1603 HIV-negative people, of whom 1225 (76%) received PrEP. Uptake was higher among those reporting condomless receptive anal intercourse (416/519 [81%] vs 809/1084 [75%], p=0·003) and having serological evidence of herpes (612/791 [77%] vs 613/812 [75%] p=0·03). Of those receiving PrEP, HIV incidence was 1·8 infections per 100 person-years, compared with 2·6 infections per 100 person-years in those who concurrently did not choose PrEP (HR 0·51, 95% CI 0·26–1·01, adjusted for sexual behaviours), and 3·9 infections per 100 person-years in the placebo group of the previous randomised phase (HR 0·49, 95% CI 0·31–0·77). Among those receiving PrEP, HIV incidence was 4·7 infections per 100 person-years if drug was not detected in dried blood spots, 2·3 infections per 100 person-years if drug concentrations suggested use of fewer than two tablets per week, 0·6 per 100 person-years for use of two to three tablets per week, and 0·0 per 100 person-years for use of four or more tablets per week (p<0·0001). PrEP drug concentrations were higher among people of older age, with more schooling, who reported non-condom receptive anal intercourse, who had more sexual partners, and who had a history of syphilis or herpes. PrEP uptake was high when made available free of charge by experienced providers. The effect of PrEP is increased by greater uptake and adherence during periods of higher risk. Drug concentrations in dried blood spots are strongly correlated with protective benefit. US National Institutes of Health.

Background Since January 2017, the recommended first-line antiretroviral regimen in Brazil is the fixed-dose combination of tenofovir plus lamivudine with dolutegravir (TL + D). According to the literature, integrase resistance-associated mutations (INRAMs) are rarely found upon virologic failure to first-line dolutegravir plus two nucleoside reverse transcriptase inhibitors. We evaluated the HIV antiretroviral genotypic resistance profile of patients referred for genotyping in the public health system who failed first-line TL + D after at least six months of therapy on or before December 31, 2018. Methods HIV Sanger sequences of the pol gene were generated from plasma of patients with confirmed virologic failure to first-line TL + D in the Brazilian public health system before December 31, 2018. Results One hundred thirteen individuals were included in the analysis. Major INRAMs were detected in seven patients (6.19%), four with R263K, one with G118R, one with E138A, and one with G140R. Four patients with major INRAMs also had the K70E and M184V mutations in the RT gene. Sixteen (14.2%) additional individuals presented minor INRAMs, and five (4,42%) patients had both major and minor INRAMS. Thirteen (11.5%) patients also presented mutations in the RT gene selected by tenofovir and lamivudine, including four with both the K70E and M184V mutations and four with only M184V. The integrase mutations L101I and T124A, which are in the in vitro pathway for integrase inhibitor resistance, were found in 48 and 19 patients, respectively. Mutations not related to TL + D, thus probable transmitted resistance mutations (TDR), were present in 28 patients (24.8%): 25 (22.1%) to nucleoside reverse transcriptase inhibitors, 19 (16.8%) to non-nucleoside reverse transcriptase inhibitors, and 6 (5.31%) to protease inhibitors. Conclusions In marked contrast to previous reports, we report a relatively high frequency of INRAMs among selected patients failing first-line TL + D in the public health system in Brazil. Possible reasons for this discrepancy include delays in detecting virologic failure, patients inadvertently on dolutegravir monotherapy, TDR, and/or infecting subtype.

In HIV-1 infection, a population of latently infected cells facilitates viral persistence despite antiretroviral therapy (ART). With the aim of identifying individuals in whom ART might induce a period of viraemic control on stopping therapy, we hypothesised that quantification of the pool of latently infected cells in primary HIV-1 infection (PHI) would predict clinical progression and viral replication following ART. We measured HIV-1 DNA in a highly characterised randomised population of individuals with PHI. We explored associations between HIV-1 DNA and immunological and virological markers of clinical progression, including viral rebound in those interrupting therapy. In multivariable analyses, HIV-1 DNA was more predictive of disease progression than plasma viral load and, at treatment interruption, predicted time to plasma virus rebound. HIV-1 DNA may help identify individuals who could safely interrupt ART in future HIV-1 eradication trials. Clinical trial registration: ISRCTN76742797 and EudraCT2004-000446-20 HIV is a virus that can hide in, and hijack, the cells of the immune system and force them to make new copies of the virus. This eventually destroys the infected cells and weakens the ability of a person with HIV to fight off infections and disease. If diagnosed early and treated, most people with HIV now live long and healthy lives and do not develop AIDS—the last stage of HIV infection when previously harmless, opportunistic infections can become life-threatening. However, there are still numerous hurdles and challenges that must be overcome before a cure for HIV/AIDS can be developed. Treatment with drugs called antiretrovirals can reduce the amount of the HIV virus circulating in an infected person's bloodstream to undetectable levels. However, when HIV infects a cell, the virus inserts a copy of its genetic material into the cell's DNA—and, for most patients, antiretroviral treatment does not tackle these ‘hidden viruses’. As such, and in spite of their side-effects, antiretroviral drugs have to be taken for life in case the hidden viruses re-emerge. As research into a cure for HIV/AIDS gathers momentum, patients who might be candidates for new experimental treatments will need to be identified. Although it is not recommended as part of standard clinical care, the only way to test if a patient's viral levels would remain suppressed without the drugs would be to temporarily stop the treatment under the close supervision of a physician. As such, a new method is needed to identify if there are patients who might benefit from stopping antiretroviral therapy, and more importantly, those who might not. Williams, Hurst et al. have now tested whether measuring the levels of HIV DNA directly might help to predict if, and when, the virus might re-emerge (or rebound). In a group of HIV patients participating in a clinical trial, those with higher levels of HIV DNA at the point that the treatment was stopped were found to experience faster viral rebound than those with lower levels of HIV DNA. This method could therefore identify those patients who are at the greatest risk of HIV viral rebound, and are therefore unlikely to benefit if their treatment is interrupted. Williams, Hurst et al. also found that measuring the levels of HIV DNA could help to predict how the disease would progress in treated and untreated patients. Furthermore, these predictions were more accurate than those based on measuring the amount of the virus circulating in a patient's body. The next challenge is to identify other methods to distinguish patients who may remain ‘virus-free’ for a period without treatment, from those who would not. With this achieved, it might be possible to identify the mechanisms that determine why the virus comes back and so develop new treatments to stop this happening. This would make developing a cure for HIV/AIDS a much more tangible prospect.

Background Predictors of the outcome of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection remain to be fully determined. We evaluated selected viral characteristics and immunological responses that might predict and/or correlate to the clinical outcome of COVID-19. Methods For individuals developing divergent clinical outcomes, the magnitude and breadth of T cell-mediated responses were measured within 36 h of symptom onset. Peripheral Blood Mononuclear Cells (PBMCs) were subjected to in vitro stimulation with SARS-CoV-2-based peptides. In addition, SARS-CoV-2 sequences were generated by metagenome, and HLA typing was performed using Luminex technology. Findings CD4 + T cell activation was negatively correlated with SARS-CoV-2 basal viral load in patients with severe COVID-19 ( p  = 0·043). The overall cellular immune response, as inferred by the IFN-γ signal, was higher at baseline for patients who progressed to mild disease compared to patients who progressed to severe disease ( p  = 0·0044). Subjects with milder disease developed higher T cell responses for MHC class I and II-restricted peptides ( p  = 0·033). Interpretation Mounting specific cellular immune responses in the first days after symptom onset, as inferred by IFN-γ magnitude in the ELISPOT assay, may efficiently favor a positive outcome. In contrast, progression to severe COVID-19 was accompanied by stronger cellular immune responses, higher CD4 + T cell activation, and a higher number of in silico predicted high-affinity class I HLA alleles.

The unparalleled success of combination antiretroviral therapy (cART) is based on the combination of three drugs from two classes. There is insufficient evidence whether simplification to ritonavir boosted protease inhibitor (PI/r) monotherapy in virologically suppressed HIV-infected patients is effective and safe to reduce cART side effects and costs. We systematically searched Medline, Embase, the Cochrane Library, conference proceedings and trial registries to identify all randomised controlled trials comparing PI/r monotherapy to cART in suppressed patients. We calculated in an intention to treat (loss-of follow-up, discontinuation of assigned drugs equals failure) and per-protocol analysis (exclusion of protocol violators following randomisation) and based on three different definitions for virological failure pooled risk ratios for remaining virologically suppressed. We identified 10 trials comparing 3 different PIs with cART based on a PI/r plus 2 reverse transcriptase inhibitors in 1189 patients. With the most conservative approach (viral load <50 copies/ml on two consecutive measurements), the risk ratios for viral suppression at 48 weeks of PI/r monotherapy compared to cART were in the ITT analysis 0.94 8 (95% CI 0.89 to 1.00) p = 0.06; risk difference -0.06 (95%CI -0.11 to 0) p = 0.05, p for heterogeneity  = 0.08, I(2) = 43.1%) and in the PP analysis 0.93 ((95%CI 0.90 to 0.97) p<0.001; risk difference -0.07 (95%CI -0.10 to -0.03) p<0.001, p for heterogeneity  = 0.44, I(2) = 0%). Reintroduction of cART in 44 patients with virological failure led in 93% to de-novo viral suppression. Virologically well suppressed HIV-infected patients have a lower chance to maintain viral suppression when switching from cART to PI/r monotherapy. Failing patients achieve high rates of de-novo viral suppression following reintroduction of reverse transcriptase inhibitors.

A minority of HIV-1 positive individuals treated with antiretroviral therapy (ART) in primary HIV-1 infection (PHI) maintain viral suppression on stopping. Whether this is related to ART duration has not been explored. And Methods: Using SPARTAC trial data from individuals recruited within 6 months of seroconversion, we present an observational analysis investigating whether duration of ART was associated with post-treatment viraemic control. Kaplan-Meier estimates, logistic regression and Cox models were used. 165 participants reached plasma viral loads (VL) <400 copies/ml at the time of stopping therapy (ART stop). After ART stop, 159 experienced confirmed VL ≥400 copies/ml during median (IQR) follow-up of 167 (108,199) weeks. Most participants experienced VL rebound within 12 weeks from ART stop, however, there was a suggestion of a higher probability of remaining <400 copies/ml for those on ART >12 weeks compared to ≤12 weeks (p=0.061). Cumulative probabilities of remaining <400 copies/ml at 12, 52 and 104 weeks after ART stop were 21% (95%CI=13,30), 4% (1,9), and 4% (1,9) for ≤12 weeks ART, and 32% (22,42), 14% (7,22), and 5% (2,11) for >12 weeks. In multivariable regression, ART for >12 weeks was independently associated with a lower probability of being ≥400 copies/ml within 12 weeks of ART stop (OR=0.11 (95%CI=0.03,0.34), p<0.001)). In Cox models of time to VL ≥400 after 12 weeks, we only found an association with female sex (OR=0.2, p=0.001). Longer ART duration in PHI was associated with a higher probability of viral control after ART stop. Controlled-Trials.com 76742797 http://www.controlled-trials.com/ISRCTN76742797.

Two randomised, placebo-controlled trials—BENCHMRK-1 and BENCHMRK-2—investigated the efficacy and safety of raltegravir, an HIV-1 integrase strand-transfer inhibitor. We report final results of BENCHMRK-1 and BENCHMRK-2 combined at 3 years (the end of the double-blind phase) and 5 years (the end of the study). Integrase-inhibitor-naive patients with HIV resistant to three classes of drug and who were failing antiretroviral therapy were enrolled. Patients were randomly assigned (2:1) to raltegravir 400 mg twice daily or placebo, both with optimised background treatment. Patients and investigators were masked to treatment allocation until week 156, after which all patients were offered open-label raltegravir until week 240. The primary endpoint was previously assessed at 16 weeks. We assessed long-term efficacy with endpoints of the proportion of patients with an HIV viral load of less than 50 copies per mL and less than 400 copies per mL, and mean change in CD4 cell count, at weeks 156 and 240. 1012 patients were screened for inclusion. 462 were treated with raltegravir and 237 with placebo. At week 156, 51% in the raltegravir group versus 22% in the placebo group (non-completer classed as failure) had viral loads of less than 50 copies per mL, and 54% versus 23% had viral loads of less than 400 copies per mL. Mean CD4 cell count increase (analysed by an observed failure approach) was 164 cells per μL versus 63 cells per μL. After week 156, 251 patients (54%) from the raltegravir group and 47 (20%) from the placebo group entered the open-label raltergravir phase; 221 (47%) versus 44 (19%) completed the entire study. At week 240, viral load was less than 50 copies per mL in 193 (42%) of all patients initially assigned to raltegravir and less than 400 copies per mL in 210 (45%); mean CD4 cell count increased by 183 cells per μL. Virological failure occurred in 166 raltegravir recipients (36%) during the double-blind phase and in 17 of all patients (6%) during the open-label phase. The most common drug-related adverse events at 5 years in both groups were nausea, headache, and diarrhoea, and occurred in similar proportions in each group. Laboratory test results were similar in both treatment groups and showed little change after year 2. Raltegravir has a favourable long-term efficacy and safety profile in integrase-inhibitor-naive patients with triple-class resistant HIV in whom antiretroviral therapy is failing. Raltegravir is an alternative for treatment-experienced patients, particularly those with few treatment options. Merck Sharp & Dohme.

Background. Blinded clinical trials have reported a modest and transient \"start-up syndrome\" with initiation of tenofovir-based pre-exposure prophylaxis (PrEP). We evaluate this phenomenon and its effect on adherence in an open-label PrEP study. Methods. In the iPrEx open-label extension (OLE) study, an 18-month open-label, multi-site PrEP cohort taking daily oral coformulated tenofovir/emtricitabine, we examined the prevalence and duration of PrEP-associated symptoms and their effect on adherence, assessed by drug levels in dried blood spots tested monthly for the first 3 months. Results. Symptom reports peaked within the first month, with 39% reporting potentially PrEP-related symptoms compared to 22% at baseline. Symptoms largely resolved to pre-PrEP levels by 3 months. Symptoms varied substantially in frequency by study site (range in 1-month symptoms: 11% to 70%). Nongastrointestinal (GI) symptoms were not associated with adherence (odds ratio [OR] = 1.2, 95% confidence interval [CI], .4–3.7); however, GI-associated symptoms in the first 4 weeks were inversely associated with adherence at 4 weeks (OR = 0.47, 95% CI, .23–.96). Reports of GI symptoms were associated with 7% (95% CI, 4%–11%) of suboptimal adherence in this cohort. Conclusions. PrEP-associated symptoms in the open-label setting occur in a minority of users and largely resolve within 3 months. GI symptoms are associated with a modest reduction in PrEP adherence, but good adherence is possible even in the presence of frequent symptom reports. Clinical Trials Registration. Clinicaltrials.gov NCT00458393.