Publications by authors named "Sharon A Riddler"

Introduction: Vesatolimod is a Toll-like receptor-7 (TLR7) agonist in clinical development as part of a combination regimen for human immunodeficiency virus (HIV) cure. Influenza-like symptoms associated with TLR7-mediated immune activation have been reported in clinical trials of vesatolimod. Therefore, a broader understanding of the safety profile of vesatolimod and association with dose and mechanism of action will help inform future clinical studies.

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Twelve weeks of dipyridamole increased extracellular adenosine levels and decreased T cell activation in people with HIV. In this analysis, we investigated the effect of dipyridamole on HIV-specific T cell responses. We compared changes in Gag- and Env-specific T cell responses using intracellular cytokine staining, following 12 weeks of dipyridamole treatment vs placebo.

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Although antiretroviral therapy (ART) is highly effective for the treatment of HIV-1 infection to suppress virus in the blood, HIV persists in tissues. HIV persistence in the tissues is due to numerous factors, and one of those factors are antiretroviral (ARV) concentrations. ARV concentrations in tissues must be adequate to suppress HIV at the sites of action.

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Background: On-demand topical products could be an important tool for human immunodeficiency virus (HIV) prevention. We evaluated the safety, pharmacokinetics, and ex vivo pharmacodynamics of a tenofovir alafenamide/elvitegravir (TAF/EVG, 20 mg/16 mg) insert administered rectally.

Methods: MTN-039 was a phase 1, open-label, single-arm, 2-dose study.

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Article Synopsis
  • - The study examined the effects of starting antiretroviral therapy (ART) during acute or early HIV infection on the viral reservoir and immune responses in participants from various regions.
  • - Results showed that starting ART earlier resulted in lower levels of HIV DNA in the blood, particularly for those who began treatment in the very early stages of infection, but it did not fully eliminate the presence of HIV-infected cells.
  • - Despite achieving viral suppression at 48 weeks, the study found no strong correlation between HIV DNA levels and the strength of HIV-specific T cell immune responses, suggesting that early treatment may reduce, but not completely prevent, viral rebound after stopping ART.
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Antiretroviral therapy (ART) is highly effective for the treatment of HIV-1 infection. ART previously consisted of concomitant administration of many drugs, multiple times per day. Currently, ART generally consists of two- or three-drug regimens once daily as fixed-dose combinations.

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Article Synopsis
  • * They analyzed data from nearly 5,000 participants prior to starting ART and over 3,000 at 48 weeks on ART, considering factors like age, sex, and genetic similarities to assess variability in CD4 T-cell counts.
  • * Although the polygenic score (PGSlymph) had a minimal impact (<1%) on the variability in CD4 T-cell recovery, it showed some significant associations in individuals of African ancestry, particularly when included in more
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Although current antiretroviral therapy (ART) effectively suppresses HIV in the blood, regimens may fail due to suboptimal treatment history and non-adherence to ART. In these scenarios, accumulation of viral resistance mutations to ART drug classes may occur. For these treatment-experienced people living with HIV (PLWH), activity against resistant viral strains is required; lack of therapeutic efficacy will result in continued viral replication and progression to acquired immunodeficiency syndrome.

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Fourteen people with human immunodeficiency virus type 1 had longitudinal measurements of intact, defective, and total proviral DNA over the course of two decades of antiretroviral therapy. Three patterns of intact proviral DNA decay were revealed: (1) biphasic decline with markedly slower second-phase decline, (2) initial decline that transitions to a zero-slope plateau, and (3) initial decline followed by later increases in intact proviral DNA. Defective proviral DNA levels were essentially stable.

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Article Synopsis
  • Breakthrough SARS-CoV-2 infections in vaccinated individuals generally lead to milder disease compared to unvaccinated people, highlighting the benefits of vaccination during the pandemic.
  • In a study involving AZD1222 (ChAdOx1 nCoV-19) vaccinees, results showed they experienced lower incidence, shorter duration of symptoms, and reduced viral loads compared to placebo recipients.
  • Vaccinated individuals exhibited strong immune responses, including increased antibody production and T-cell responses, which were linked to better control of the virus and reduced transmission potential.
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Widespread availability of antiretroviral therapies (ART) for HIV-1 have generated considerable interest in understanding the pharmacogenomics of ART. In some individuals, ART has been associated with excessive weight gain, which disproportionately affects women of African ancestry. The underlying biology of ART-associated weight gain is poorly understood, but some genetic markers which modify weight gain risk have been suggested, with more genetic factors likely remaining undiscovered.

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Data to inform behaviorally congruent delivery of rectal microbicides as lubricants are scant. Dapivirine (DPV) is a nonnucleoside reverse transcriptase inhibitor which has been demonstrated to be well-tolerated and efficacious in multiple clinical trials when used in a vaginal ring formulation. DPV gel administered rectally with an applicator was found to be well-tolerated in a phase 1 clinical trial.

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Research suggests that women's experience of intimate partner violence (IPV) is associated with poor engagement in HIV care and treatment. However, most studies have been cross-sectional and conducted in North America. We examined the association between physical IPV and HIV care outcomes in a prospective cohort study of women living with HIV (WLHIV) in Malawi, South Africa, Uganda, and Zimbabwe.

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Antiretroviral therapy (ART) for HIV-1 has dramatically improved outcomes for people living with HIV-1 but requires life-long adherence and can be associated with short and long-term toxicity. Numerous pre-clinical and clinical investigations are underway to develop therapies for immune control of HIV-1 in the absence of ART. The success of chimeric antigen receptor (CAR) cell therapy for hematological malignancy has renewed efforts to develop and investigate CAR cells as strategies to enhance HIV-1 immunity, enable virus control or elimination, and allow ART-free HIV-1 remission.

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As a type of relatively new methodology, the transcriptome-wide association study (TWAS) has gained interest due to capacity for gene-level association testing. However, the development of TWAS has outpaced statistical evaluation of TWAS gene prioritization performance. Current TWAS methods vary in underlying biological assumptions about tissue specificity of transcriptional regulatory mechanisms.

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Background: During early HIV-1 infection, immunodominant T cell responses to highly variable epitopes lead to the establishment of immune escape virus variants. Here we assessed a type 1-polarized monocyte-derived dendritic cell (MDC1)-based approach to selectively elicit cytotoxic T lymphocyte (CTL) responses against highly conserved and topologically important HIV-1 epitopes in HIV-1-infected individuals from the Thailand RV254/SEARCH 010 cohort who initiated antiretroviral therapy (ART) during early infection (Fiebig stages I-IV).

Methods: Autologous MDC1 were used as antigen presenting cells to induce in vitro CTL responses against HIV-1 Gag, Pol, Env, and Nef as determined by flow cytometry and ELISpot assay.

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Background: We had previously conducted a double-blind, randomized placebo-controlled, partial cross-over trial showing that 12 weeks of dipyridamole decreased CD8 T-cell activation among treated HIV(+) individuals by increasing extracellular adenosine levels.

Methods: In this substudy, rectosigmoid biopsies were obtained from 18 participants (9 per arm), to determine whether 12 weeks of dipyridamole affects mucosal immune cells. Participants randomized to placebo were then switched to dipyridamole for 12 weeks while the treatment arm continued dipyridamole for another 12 weeks.

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Background: Treatment with vesatolimod, an investigational, oral, toll-like receptor 7 (TLR7) agonist, leads to sustained viral remission in some non-human primates when combined with anti-envelope antibodies or therapeutic vaccines. We report results of a Phase Ib study evaluating safety, pharmacokinetics, and pharmacodynamics of vesatolimod in adults living with human immunodeficiency virus (HIV)-1.

Methods: In this double-blind, multicenter, placebo-controlled trial, participants on antiretroviral therapy with screening plasma HIV-1 RNA levels <50 copies/mL were randomized (6:2) to receive 6-10 doses of vesatolimod (1-12 mg) or matching placebo orally every other week in sequential dose-escalation cohorts.

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Background: Unwanted weight gain affects some people living with human immunodeficiency virus (HIV) who are prescribed integrase strand transfer inhibitors (INSTIs). Mechanisms and risk factors are incompletely understood.

Methods: We utilized 2 cohorts to study pharmacogenetics of weight gain following switch from efavirenz- to INSTI-based regimens.

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Background: HIV-1 proviruses persist in people on antiretroviral therapy (ART) but most are defective and do not constitute a replication-competent reservoir. The decay of infected cells carrying intact compared with defective HIV-1 proviruses has not been well defined in people on ART.

Methods: We separately quantified intact and defective proviruses, residual plasma viremia, and markers of inflammation and activation in people on long-term ART.

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Objective: We evaluated frequencies of T cells with high PD-1 expression (PD-1) before and after long-term effective antiretroviral therapy (ART), and determined if frequencies on-ART correlated positively with measures of HIV persistence and negatively with HIV-specific responses.

Methods: We enrolled individuals who started ART during chronic infection and had durable suppression of viremia for at least 4 years (N = 99). We assessed PD-1 T-cell frequencies at timepoints pre-ART and on-ART using flow cytometry, and evaluated how frequencies on-ART are associated with measures of HIV persistence, HIV-specific immune responses, and immune activation levels.

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Objectives: Assessment of safety is an integral part of real-time monitoring in clinical trials. In HIV prevention research, safety of investigational products and trial participation has been expanded to include monitoring for 'social harms', generally defined as negative consequences of trial participation that may manifest in social, psychological, or physical ways. Further research on social harms within HIV prevention research is needed to understand the potential safety risks for women and advance the implementation of prevention methods in real-world contexts.

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Background: Adenosine is a potent immunoregulatory nucleoside produced during inflammatory states to limit tissue damage. We hypothesized that dipyridamole, which inhibits cellular adenosine uptake, could raise the extracellular adenosine concentration and dampen chronic inflammation associated with human immunodeficiency virus (HIV) type 1.

Methods: Virally suppressed participants receiving antiretroviral therapy were randomized 1:1 for 12 weeks of dipyridamole (100 mg 4 times a day) versus placebo capsules.

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Contraceptive adherence during acute and recent HIV-1 infection is important to maternal and child health given the elevated risk of vertical HIV-1 transmission and additional complications of pregnancy. Injectable contraception (IC) is the most common non-barrier modern contraception method used in sub-Saharan Africa (SSA). Adherence to IC after HIV-1 seroconversion is not well understood.

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