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1.
J Virol ; 93(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31434737

RESUMO

HIV Vaccine Trials Network (HVTN) 505 was a phase 2b efficacy trial of a DNA/recombinant adenovirus 5 (rAd5) HIV vaccine regimen. Although the trial was stopped early for lack of overall efficacy, later correlates of risk and sieve analyses generated the hypothesis that the DNA/rAd5 vaccine regimen protected some vaccinees from HIV infection yet enhanced HIV infection risk for others. Here, we assessed whether and how host Fc gamma receptor (FcγR) genetic variations influenced the DNA/rAd5 vaccine regimen's effect on HIV infection risk. We found that vaccine receipt significantly increased HIV acquisition compared with placebo receipt among participants carrying the FCGR2C-TATA haplotype (comprising minor alleles of four FCGR2C single-nucleotide polymorphism [SNP] sites) (hazard ratio [HR] = 9.79, P = 0.035) but not among participants without the haplotype (HR = 0.86, P = 0.67); the interaction of vaccine and haplotype effect was significant (P = 0.034). Similarly, vaccine receipt increased HIV acquisition compared with placebo receipt among participants carrying the FCGR3B-AGA haplotype (comprising minor alleles of the 3 FCGR3B SNPs) (HR = 2.78, P = 0.058) but not among participants without the haplotype (HR = 0.73, P = 0.44); again, the interaction of vaccine and haplotype was significant (P = 0.047). The FCGR3B-AGA haplotype also influenced whether a combined Env-specific CD8+ T-cell polyfunctionality score and IgG response correlated significantly with HIV risk; an FCGR2A SNP and two FCGR2B SNPs influenced whether anti-gp140 antibody-dependent cellular phagocytosis correlated significantly with HIV risk. These results provide further evidence that Fc gamma receptor genetic variations may modulate HIV vaccine effects and immune function after HIV vaccination.IMPORTANCE By analyzing data from the HVTN 505 efficacy trial of a DNA/recombinant adenovirus 5 (rAd5) vaccine regimen, we found that host genetics, specifically Fc gamma receptor genetic variations, influenced whether receiving the DNA/rAd5 regimen was beneficial, neutral, or detrimental to an individual with respect to HIV-1 acquisition risk. Moreover, Fc gamma receptor genetic variations influenced immune responses to the DNA/rAd5 vaccine regimen. Thus, Fc gamma receptor genetic variations should be considered in the analysis of future HIV vaccine trials and the development of HIV vaccines.


Assuntos
Linfócitos B/virologia , Infecções por HIV/virologia , HIV-1/genética , Polimorfismo de Nucleotídeo Único , Receptores de IgG/genética , Vacinas de DNA/administração & dosagem , Anticorpos Monoclonais/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Estudos de Casos e Controles , Ensaios Clínicos Fase II como Assunto , Vetores Genéticos/administração & dosagem , Infecções por HIV/epidemiologia , Infecções por HIV/genética , Infecções por HIV/imunologia , Soropositividade para HIV , HIV-1/imunologia , Humanos , Incidência , Fagocitose , Estados Unidos/epidemiologia , Vacinação , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
2.
PLoS Biol ; 14(3): e1002372, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26933962

RESUMO

In the last 15 years, antiretroviral therapy (ART) has been the most globally impactful life-saving development of medical research. Antiretrovirals (ARVs) are used with great success for both the treatment and prevention of HIV infection. Despite these remarkable advances, this epidemic grows relentlessly worldwide. Over 2.1 million new infections occur each year, two-thirds in women and 240,000 in children. The widespread elimination of HIV will require the development of new, more potent prevention tools. Such efforts are imperative on a global scale. However, it must also be recognised that true containment of the epidemic requires the development and widespread implementation of a scientific advancement that has eluded us to date--a highly effective vaccine. Striving for such medical advances is what is required to achieve the end of AIDS.


Assuntos
Infecções por HIV/prevenção & controle , Vacinas contra a AIDS , Anti-Infecciosos Locais , Antirretrovirais/uso terapêutico , Anticorpos Neutralizantes , Humanos , Pediatria
3.
J Infect Dis ; 217(8): 1280-1288, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29325070

RESUMO

Background: HVTN 505 was a human immunodeficiency virus type 1 (HIV-1) preventive vaccine efficacy trial of a DNA/recombinant adenovirus serotype 5 (rAd5) vaccine regimen. We assessed antibody responses measured 1 month after final vaccination (month 7) as correlates of HIV-1 acquisition risk. Methods: Binding antibody responses were quantified in serum samples from 25 primary endpoint vaccine cases (diagnosed with HIV-1 infection between month 7 and month 24) and 125 randomly sampled frequency-matched vaccine controls (HIV-1 negative at month 24). We prespecified for a primary analysis tier 6 antibody response biomarkers that measure immunoglobulin G (IgG) and immunoglobulin A (IgA) binding to Env proteins and 2 previously assessed T-cell response biomarkers. Results: Envelope-specific IgG responses were significantly correlated with decreased HIV-1 risk. Moreover, the interaction of IgG responses and Env-specific CD8+ T-cell polyfunctionality score had a highly significant association with HIV-1 risk after adjustment for multiple comparisons. Conclusions: Vaccinees with higher levels of Env IgG have significantly decreased HIV-1 risk when CD8+ T-cell responses are low. Moreover, vaccinees with high CD8+ T-cell responses generally have low risk, and those with low CD8+ T-cell and low Env antibody responses have high risk. These findings suggest the critical importance of inducing a robust IgG Env response when the CD8+ T-cell response is low.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos T CD8-Positivos/fisiologia , Infecções por HIV/prevenção & controle , Formação de Anticorpos/imunologia , Anticorpos Anti-HIV/sangue , HIV-1/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Masculino
4.
Vet Anaesth Analg ; 45(4): 529-538, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29705687

RESUMO

OBJECTIVE: To test the hypothesis that plasma propofol concentration (PPC) is associated with anesthetic effect in koi carp administered propofol by immersion. STUDY DESIGN: Prospective study. ANIMALS: Twenty mature koi carp (mean ± standard deviation, 409.4 ± 83.7 g). METHODS: Fish were immersed in propofol (5 mg L-1). Physiological variables and induction and recovery times were recorded. In phase I, blood was sampled for PPC immediately following induction and at recovery. In phase II, following induction, fish were maintained with propofol (4 mg L-1) via a recirculating system for 20 minutes. Following established induction, blood was sampled at 1, 10 and 20 minutes. In phase III (n = 19), fish were anesthetized as in phase II with blood sampled nine times in a sparse sampling strategy. Simultaneously, a pharmacodynamics rubric was used to evaluate anesthetic depth. PPC was determined using high performance liquid chromatography with fluorescence detection. Following evaluation of normality, data were analyzed using paired t test or Spearman correlation test (significance was set at p < 0.05). RESULTS: In phase I, mean PPCs at induction (20.12 µg mL-1) and recovery (11.62 µg mL-1) were different (p < 0.001). In phase II, only mean PPCs at induction (17.92 µg mL-1) and 10 minutes (21.50 µg mL-1) were different (p = 0.013). In phase III, a correlation between PPCs and the pharmacodynamic rubric scores was found (p < 0.001, r = -0.93). There was no correlation between PPCs and recovery time (p = 0.057, r = 0.433). A two-compartment open model was chosen for the pharmacokinetic model. Absorption rate constant, elimination rate constant and intercompartmental rate constant were 0.48, 0.006 and 0.02 minute-1, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Measurable PPCs were achieved in koi carp anesthetized with propofol by immersion. Anesthetic depth of fish was negatively correlated with PPCs, but recovery time was not.


Assuntos
Carpas/metabolismo , Hipnóticos e Sedativos/farmacocinética , Propofol/farmacocinética , Período de Recuperação da Anestesia , Animais , Cromatografia Líquida de Alta Pressão/veterinária , Sedação Profunda/métodos , Sedação Profunda/veterinária , Frequência Cardíaca/efeitos dos fármacos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/sangue , Hipnóticos e Sedativos/farmacologia , Imersão , Propofol/administração & dosagem , Propofol/sangue , Propofol/farmacologia
5.
J Infect Dis ; 215(9): 1376-1385, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28199679

RESUMO

Background: It is important to identify vaccine-induced immune responses that predict the preventative efficacy of a human immunodeficiency virus (HIV)-1 vaccine. We assessed T-cell response markers as correlates of risk in the HIV Vaccine Trials Network (HVTN) 505 HIV-1 vaccine efficacy trial. Methods: 2504 participants were randomized to DNA/rAd5 vaccine or placebo, administered at weeks 0, 4, 8, and 24. Peripheral blood mononuclear cells were obtained at week 26 from all 25 primary endpoint vaccine cases and 125 matched vaccine controls, and stimulated with vaccine-insert-matched peptides. Primary variables were total HIV-1-specific CD4+ T-cell magnitude and Env-specific CD4+ polyfunctionality. Four secondary variables were also assessed. Immune responses were evaluated as predictors of HIV-1 infection among vaccinees using Cox proportional hazards models. Machine learning analyses identified immune response combinations best predicting HIV-1 infection. Results: We observed an unexpectedly strong inverse correlation between Env-specific CD8+ immune response magnitude and HIV-1 infection risk (hazard ratio [HR] = 0.18 per SD increment; P = .04) and between Env-specific CD8+ polyfunctionality and infection risk (HR = 0.34 per SD increment; P < .01). Conclusions: Further research is needed to determine if these immune responses are predictors of vaccine efficacy or markers of natural resistance to HIV-1 infection.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Vacinas contra a AIDS/administração & dosagem , Adenoviridae/genética , Análise de Variância , Biologia Computacional , Citocinas/imunologia , Vetores Genéticos , Infecções por HIV/prevenção & controle , Humanos , Aprendizado de Máquina , Risco
6.
J Infect Dis ; 213(4): 541-50, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26475930

RESUMO

BACKGROUND: Increasing the breadth of human immunodeficiency virus type 1 (HIV-1) vaccine-elicited immune responses or targeting conserved regions may improve coverage of circulating strains. HIV Vaccine Trials Network 083 tested whether cellular immune responses with these features are induced by prime-boost strategies, using heterologous vectors, heterologous inserts, or a combination of both. METHODS: A total of 180 participants were randomly assigned to receive combinations of adenovirus vectors (Ad5 or Ad35) and HIV-1 envelope (Env) gene inserts (clade A or B) in a prime-boost regimen. RESULTS: T-cell responses to heterologous and homologous insert regimens targeted a similar number of epitopes (ratio of means, 1.0; 95% confidence interval [CI], .6-1.6; P = .91), but heterologous insert regimens induced significantly more epitopes that were shared between EnvA and EnvB than homologous insert regimens (ratio of means, 2.7; 95% CI, 1.2-5.7; P = .01). Participants in the heterologous versus homologous insert groups had T-cell responses that targeted epitopes with greater evolutionary conservation (mean entropy [±SD], 0.32 ± 0.1 bits; P = .003), and epitopes recognized by responders provided higher coverage (49%; P = .035). Heterologous vector regimens had higher numbers of total, EnvA, and EnvB epitopes than homologous vector regimens (P = .02, .044, and .045, respectively). CONCLUSIONS: These data demonstrate that vaccination with heterologous insert prime boosting increased T-cell responses to shared epitopes, while heterologous vector prime boosting increased the number of T-cell epitopes recognized. CLINICAL TRIALS REGISTRATION: NCT01095224.


Assuntos
Vacinas contra a AIDS/imunologia , HIV-1/imunologia , Linfócitos T/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/administração & dosagem , Adenoviridae/genética , Adolescente , Adulto , Método Duplo-Cego , Portadores de Fármacos , Epitopos de Linfócito T/imunologia , Feminino , Vetores Genéticos , Antígenos HIV/genética , Antígenos HIV/imunologia , Humanos , Esquemas de Imunização , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Adulto Jovem , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
7.
N Engl J Med ; 369(22): 2083-92, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-24099601

RESUMO

BACKGROUND: A safe and effective vaccine for the prevention of human immunodeficiency virus type 1 (HIV-1) infection is a global priority. We tested the efficacy of a DNA prime-recombinant adenovirus type 5 boost (DNA/rAd5) vaccine regimen in persons at increased risk for HIV-1 infection in the United States. METHODS: At 21 sites, we randomly assigned 2504 men or transgender women who have sex with men to receive the DNA/rAd5 vaccine (1253 participants) or placebo (1251 participants). We assessed HIV-1 acquisition from week 28 through month 24 (termed week 28+ infection), viral-load set point (mean plasma HIV-1 RNA level 10 to 20 weeks after diagnosis), and safety. The 6-plasmid DNA vaccine (expressing clade B Gag, Pol, and Nef and Env proteins from clades A, B, and C) was administered at weeks 0, 4, and 8. The rAd5 vector boost (expressing clade B Gag-Pol fusion protein and Env glycoproteins from clades A, B, and C) was administered at week 24. RESULTS: In April 2013, the data and safety monitoring board recommended halting vaccinations for lack of efficacy. The primary analysis showed that week 28+ infection had been diagnosed in 27 participants in the vaccine group and 21 in the placebo group (vaccine efficacy, -25.0%; 95% confidence interval, -121.2 to 29.3; P=0.44), with mean viral-load set points of 4.46 and 4.47 HIV-1 RNA log10 copies per milliliter, respectively. Analysis of all infections during the study period (41 in the vaccine group and 31 in the placebo group) also showed lack of vaccine efficacy (P=0.28). The vaccine regimen had an acceptable side-effect profile. CONCLUSIONS: The DNA/rAd5 vaccine regimen did not reduce either the rate of HIV-1 acquisition or the viral-load set point in the population studied. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT00865566.).


Assuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/prevenção & controle , HIV-1 , Vacinas de DNA/imunologia , Vacinas contra a AIDS/efeitos adversos , Adulto , Método Duplo-Cego , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/imunologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Fenômenos Imunogenéticos , Incidência , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Pessoas Transgênero , Falha de Tratamento , Vacinas de DNA/efeitos adversos , Carga Viral , Adulto Jovem
8.
Clin Trials ; 12(4): 394-402, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25851992

RESUMO

BACKGROUND: The field of HIV prevention research has recently experienced some mixed results in efficacy trials of pre-exposure prophylaxis, vaginal microbicides, and HIV vaccines. While there have been positive trial results in some studies, in the near term, no single method will be sufficient to quell the epidemic. Improved HIV prevention methods, choices among methods, and coverage for all at-risk populations will be needed. The emergence of partially effective prevention methods that are not uniformly available raises complex ethical and scientific questions regarding the design of ongoing prevention trials. METHODS: We present here an ethical analysis regarding inclusion of pre-exposure prophylaxis in an ongoing phase IIb vaccine efficacy trial, HVTN 505. This is the first large vaccine efficacy trial to address the issue of pre-exposure prophylaxis, and the decisions made by the protocol team were informed by extensive stakeholder consultations. The key ethical concerns are analyzed here, and the process of stakeholder engagement and decision-making described. DISCUSSION: This discussion and analysis will be useful as current and future research teams grapple with ethical and scientific study design questions emerging with the rapidly expanding evidence base for HIV prevention.


Assuntos
Vacinas contra a AIDS , Ensaios Clínicos Fase II como Assunto/ética , Infecções por HIV/prevenção & controle , Profilaxia Pré-Exposição , Experimentação Humana Terapêutica/ética , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Adulto Jovem
9.
J Infect Dis ; 210(1): 99-110, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24403557

RESUMO

BACKGROUND: Clade B DNA and recombinant modified vaccinia Ankara (MVA) vaccines producing virus-like particles displaying trimeric membrane-bound envelope glycoprotein (Env) were tested in a phase 2a trial in human immunodeficiency virus (HIV)-uninfected adults for safety, immunogenicity, and 6-month durability of immune responses. METHODS: A total of 299 individuals received 2 doses of JS7 DNA vaccine and 2 doses of MVA/HIV62B at 0, 2, 4, and 6 months, respectively (the DDMM regimen); 3 doses of MVA/HIV62B at 0, 2, and 6 months (the MMM regimen); or placebo injections. RESULTS: At peak response, 93.2% of the DDMM group and 98.4% of the MMM group had binding antibodies for Env. These binding antibodies were more frequent and of higher magnitude for the transmembrane subunit (gp41) than the receptor-binding subunit (gp120) of Env. For both regimens, response rates were higher for CD4(+) T cells (66.4% in the DDMM group and 43.1% in the MMM group) than for CD8(+) T cells (21.8% in the DDMM group and 14.9% in the MMM group). Responding CD4(+) and CD8(+) T cells were biased toward Gag, and >70% produced 2 or 3 of the 4 cytokines evaluated (ie, interferon γ, interleukin 2, tumor necrosis factor α, and granzyme B). Six months after vaccination, the magnitudes of antibodies and T-cell responses had decreased by <3-fold. CONCLUSIONS: DDMM and MMM vaccinations with virus-like particle-expressing immunogens elicited durable antibody and T-cell responses.


Assuntos
Vacinas contra a AIDS/imunologia , Portadores de Fármacos , HIV-1/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/genética , Adolescente , Adulto , Feminino , Anticorpos Anti-HIV/sangue , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Linfócitos T/imunologia , Fatores de Tempo , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/genética , Vaccinia virus/genética , Adulto Jovem , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
10.
HIV Clin Trials ; 14(2): 61-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23611826

RESUMO

BACKGROUND: While persistent T-cell activation has been cross-sectionally associated with poor CD4+ T-cell restoration in HIV-infected individuals maintaining antiretroviral treatment (ART)-mediated viral suppression, it remains unclear whether CD8+ T-cell activation is of predictive effect on CD4+ T-cell recovery. OBJECTIVE: We assessed whether the extent of persistent CD8+ T-cell activation (% CD38+/HLA-DR+) in the first few years of ART-mediated viral suppression predicted subsequent CD4+ T-cell recovery in 95 subjects with up to 15 years of observation on suppressive ART. RESULTS: Lower CD8+ T-cell activation and higher naïve CD4+ T-cell frequencies (CD45RA+/CD62L+) measured at year 3 to 5 after starting ART independently predicted greater subsequent CD4+ T-cell increases. The mean CD4 count increase from year 0 to year 5 and the increase to the average of year 10 to 15 in the low CD8 activation group (≤18.5%; mean = 13%) were 342 and 458 cells/mm,3 and the increases were 248 and 349 cells/mm3 for the high CD8 activation group (≯18.5%; mean = 29%) (P = .002 and P = .016, respectively, comparing groups). At years 10 to 15, the mean CD4 counts in the groups were 579 and 484 cells/mm3, respectively (P = .026). CONCLUSION: These findings support the need to identify approaches to reduce immune activation in treated HIV disease.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Ativação Linfocitária , Adulto , Feminino , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade
12.
JAMA ; 308(4): 387-402, 2012 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-22820792

RESUMO

CONTEXT: New trial data and drug regimens that have become available in the last 2 years warrant an update to guidelines for antiretroviral therapy (ART) in human immunodeficiency virus (HIV)-infected adults in resource-rich settings. OBJECTIVE: To provide current recommendations for the treatment of adult HIV infection with ART and use of laboratory-monitoring tools. Guidelines include when to start therapy and with what drugs, monitoring for response and toxic effects, special considerations in therapy, and managing antiretroviral failure. DATA SOURCES, STUDY SELECTION, AND DATA EXTRACTION: Data that had been published or presented in abstract form at scientific conferences in the past 2 years were systematically searched and reviewed by an International Antiviral Society-USA panel. The panel reviewed available evidence and formed recommendations by full panel consensus. DATA SYNTHESIS: Treatment is recommended for all adults with HIV infection; the strength of the recommendation and the quality of the evidence increase with decreasing CD4 cell count and the presence of certain concurrent conditions. Recommended initial regimens include 2 nucleoside reverse transcriptase inhibitors (tenofovir/emtricitabine or abacavir/lamivudine) plus a nonnucleoside reverse transcriptase inhibitor (efavirenz), a ritonavir-boosted protease inhibitor (atazanavir or darunavir), or an integrase strand transfer inhibitor (raltegravir). Alternatives in each class are recommended for patients with or at risk of certain concurrent conditions. CD4 cell count and HIV-1 RNA level should be monitored, as should engagement in care, ART adherence, HIV drug resistance, and quality-of-care indicators. Reasons for regimen switching include virologic, immunologic, or clinical failure and drug toxicity or intolerance. Confirmed treatment failure should be addressed promptly and multiple factors considered. CONCLUSION: New recommendations for HIV patient care include offering ART to all patients regardless of CD4 cell count, changes in therapeutic options, and modifications in the timing and choice of ART in the setting of opportunistic illnesses such as cryptococcal disease and tuberculosis.


Assuntos
Antirretrovirais/administração & dosagem , Infecções por HIV/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS , Adulto , Antirretrovirais/efeitos adversos , Contagem de Linfócito CD4 , Esquema de Medicação , Quimioterapia Combinada , Feminino , Infecções por HIV/complicações , Hepatite B/complicações , Hepatite C/complicações , Humanos , Masculino , Adesão à Medicação , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Qualidade da Assistência à Saúde , RNA Viral/sangue , Sociedades Médicas , Falha de Tratamento
13.
J Infect Dis ; 203(7): 969-75, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21402548

RESUMO

Recently, the RV144 randomized, double-blind, efficacy trial in Thailand reported that a prime-boost human immunodeficiency virus (HIV) vaccine regimen conferred ∼30% protection against HIV acquisition. However, different analyses seemed to give conflicting results, and a heated debate ensued as scientists and the broader public struggled with their interpretation. The lack of accounting for statistical principles helped flame the debate, and we leverage these principles to provide a more scientific interpretation. We first address interpretation of frequentist results, including interpretation of P values, synthesis of results from multiple analyses (ie, intention-to-treat versus per-protocol/fully immunized), and accounting for external efficacy trials. Second, we address how Bayesian statistics, which provide clearly interpretable statements about probabilities that the vaccine efficacy takes certain values, provide more information for weighing the evidence about efficacy than do frequentist statistics alone. Third, we evaluate RV144 for completeness of end point ascertainment and integrity of blinding, necessary tasks for establishing robustly interpretable results.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Estatística como Assunto , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa/normas , Tailândia , Resultado do Tratamento
15.
J Infect Dis ; 201(5): 672-80, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20102272

RESUMO

BACKGROUND: The contribution of low frequency drug-resistant human immunodeficiency virus type 1 (HIV-1) variants to failure of antiretroviral therapy is not well defined in treatment-experienced patients. We sought to detect minor nonnucleoside reverse-transcriptase inhibitor (NNRTI)-resistant variants at the initiation of multidrug efavirenz-containing therapy in both NNRTI-naive and NNRTI-experienced patients and to determine their association with virologic response. METHODS: Plasma samples at entry and at time of virologic failure from patients enrolled in the AIDS Clinical Trials Group study 398 were analyzed by standard genotype, single-genome sequencing and allele-specific polymerase chain reaction (K103N and Y181C) to detect and quantify minor NNRTI-resistant variants. RESULTS: Minor populations of NNRTI-resistant variants that were missed by standard genotype were detected more often at study entry in NNRTI-experienced patients than NNRTI-naive patients by both single-genome sequencing (8 of 12 vs 3 of 15; P = .022) and allele-specific polymerase chain reaction (11% Y181C, 5 of 22 vs 3 of 72, respectively; P = .016). K103N variants at frequencies 11% were associated with inferior HIV-1 RNA response to efavirenz-containing therapy between entry and week 24 (change in HIV-1 RNA level, +0.5 vs -1.1 log(10) copies/mL; P < .001). CONCLUSIONS: Minor NNRTI-resistant variants were more prevalent in NNRTI-experienced patients and were associated with reduced virologic response to efavirenz-containing multidrug regimens.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Benzoxazinas/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV/genética , HIV-1/efeitos dos fármacos , Alcinos , Ciclopropanos , Variação Genética , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Humanos , Mutação de Sentido Incorreto , Plasma/virologia , Reação em Cadeia da Polimerase/métodos , Seleção Genética , Análise de Sequência de DNA , Falha de Tratamento
16.
J Clin Invest ; 131(16)2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34166231

RESUMO

BackgroundVRC01, a potent, broadly neutralizing monoclonal antibody, inhibits simian-HIV infection in animal models. The HVTN 104 study assessed the safety and pharmacokinetics of VRC01 in humans. We extend the clinical evaluation to determine intravenously infused VRC01 distribution and protective function at mucosal sites of HIV-1 entry.MethodsHealthy, HIV-1-uninfected men (n = 7) and women (n = 5) receiving VRC01 every 2 months provided mucosal and serum samples once, 4-13 days after infusion. Eleven male and 8 female HIV-seronegative volunteers provided untreated control samples. VRC01 levels were measured in serum, secretions, and tissue, and HIV-1 inhibition was determined in tissue explants.ResultsMedian VRC01 levels were quantifiable in serum (96.2 µg/mL or 1.3 pg/ng protein), rectal tissue (0.11 pg/ng protein), rectal secretions (0.13 pg/ng protein), vaginal tissue (0.1 pg/ng protein), and cervical secretions (0.44 pg/ng protein) from all recipients. VRC01/IgG ratios in male serum correlated with those in paired rectal tissue (r = 0.893, P = 0.012) and rectal secretions (r = 0.9643, P = 0.003). Ex vivo HIV-1Bal26 challenge infected 4 of 21 rectal explants from VRC01 recipients versus 20 of 22 from controls (P = 0.005); HIV-1Du422.1 infected 20 of 21 rectal explants from VRC01 recipients and 12 of 12 from controls (P = 0.639). HIV-1Bal26 infected 0 of 14 vaginal explants of VRC01 recipients compared with 23 of 28 control explants (P = 0.003).ConclusionIntravenous VRC01 distributes into the female genital and male rectal mucosa and retains anti-HIV-1 functionality, inhibiting a highly neutralization-sensitive but not a highly resistant HIV-1 strain in mucosal tissue. These findings lend insight into VRC01 mucosal infiltration and provide perspective on in vivo protective efficacy.FundingNational Institute of Allergy and Infectious Diseases and Bill & Melinda Gates Foundation.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Amplamente Neutralizantes/administração & dosagem , Anticorpos Anti-HIV/administração & dosagem , Infecções por HIV/prevenção & controle , HIV-1/imunologia , HIV-1/patogenicidade , Reto/imunologia , Vagina/imunologia , Adulto , Anticorpos Monoclonais/farmacocinética , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Técnicas In Vitro , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Mucosa/imunologia , Mucosa/virologia , Reto/virologia , Vagina/virologia , Adulto Jovem
17.
Sex Transm Dis ; 37(6): 352-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20145588

RESUMO

Limited data are available on circumcision prevalence and acceptability among Thai men to prevent human immunodeficiency virus. Of 408 high-risk heterosexual men, 12.3% were circumcised. 14.2% and 24.9% expressed willingness to be circumcised before and after circumcision education, respectively. Neonatal circumcision acceptability was relatively high. One participant underwent circumcision at 3-month follow-up.


Assuntos
Circuncisão Masculina/psicologia , Infecções por HIV/prevenção & controle , Heterossexualidade , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adolescente , Adulto , Circuncisão Masculina/estatística & dados numéricos , Infecções por HIV/epidemiologia , HIV-1 , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Tailândia/epidemiologia , Adulto Jovem
18.
HIV Clin Trials ; 11(6): 312-24, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21239359

RESUMO

BACKGROUND AND OBJECTIVE: Maximizing the durability of viral suppression is a key goal of antiretroviral therapy. The objective of AIDS Clinical Trials Group Study 372A was to determine whether the intensification strategy of adding abacavir to an effective indinavir-dual nucleoside regimen would delay the time to virologic failure. METHODS: Zidovudine-experienced subjects (n=229) on therapy with indinavir + zidovudine + lamivudine with plasma HIV-1 RNA levels<500 copies/mL were randomized to abacavir 300 mg twice daily or placebo. The primary endpoint was the time to treatment failure, defined as a composite of confirmed virologic failure (2 consecutive HIV-1 RNAs>200 copies/mL) and treatment discontinuation. RESULTS: At baseline, the study population was 88% male with a median age of 41 years and median CD4 cell count of 250/mm3. Median follow-up was 4.4 years. The primary endpoint was reached in 61/116 of abacavir versus 62/113 of placebo recipients (P=.77); virologic failure occurred in 34/116 and 42/113 patients, respectively (P=.22). There were no differences in the proportions of subjects with plasma HIV-1 RNA levels below 50 copies/mL, in CD4 cell count increases, nor adverse events between the arms. In the study, 17% of subjects developed nephrolithiasis, 2% experienced abacavir hypersensitivity, and 4.8% experienced at least 1 serious cardiovascular event (7 [6%] in the abacavir arm, 4 [3.5%] in the placebo arm). In additional secondary and post hoc analyses, rates of intermittent viremia, suppression below a plasma HIV-1 RNA level of 6 copies/mL, and HIV-1 proviral DNA levels in peripheral blood mononuclear cells were not significantly different in the 2 arms. CONCLUSIONS: The strategy of intensification with abacavir in patients who are virologically suppressed on a stable antiretroviral regimen does not confer a clinical or virologic benefit. As antiretroviral regimens have become more potent since this trial was completed, it will be even more difficult to prove that late intensification of already virologically suppressed patients will add benefit. However, studies are warranted with drugs with new mechanisms of action to determine whether the level of persistent viremia below 50 copies/ mL can be further reduced and what influence this may have on latent HIV reservoirs.


Assuntos
Fármacos Anti-HIV/farmacologia , Didesoxinucleosídeos/farmacologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Adulto , Idoso , Fármacos Anti-HIV/normas , Contagem de Linfócito CD4 , Didesoxinucleosídeos/normas , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Genótipo , Inibidores da Protease de HIV/administração & dosagem , HIV-1/genética , Humanos , Indinavir/administração & dosagem , Masculino , Pessoa de Meia-Idade , Placebos , Falha de Tratamento , Adulto Jovem , Zidovudina/administração & dosagem
19.
JAMA ; 304(3): 321-33, 2010 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-20639566

RESUMO

CONTEXT: Recent data regarding the consequences of untreated human immunodeficiency virus (HIV) infection and the expansion of treatment choices for antiretroviral-naive and antiretroviral-experienced patients warrant an update of the International AIDS Society-USA guidelines for the use of antiretroviral therapy in adults with HIV infection. OBJECTIVES: To provide updated recommendations for management of HIV-infected adults, using antiretroviral drugs and laboratory monitoring tools available in the international, developed-world setting. This report provides guidelines for when to initiate antiretroviral therapy, selection of appropriate initial regimens, patient monitoring, when to change therapy, and what regimens to use when changing. DATA SOURCES AND STUDY SELECTION: A panel with expertise in HIV research and clinical care reviewed relevant data published or presented at selected scientific conferences since the last panel report through April 2010. Data were identified through a PubMed search, review of scientific conference abstracts, and requests to antiretroviral drug manufacturers for updated clinical trials and adverse event data. DATA EXTRACTION AND SYNTHESIS: New evidence was reviewed by the panel. Recommendations were drafted by section writing committees and reviewed and edited by the entire panel. The quality and strength of the evidence were rated and recommendations were made by full panel consensus. CONCLUSIONS: Patient readiness for treatment should be confirmed before initiation of antiretroviral treatment. Therapy is recommended for asymptomatic patients with a CD4 cell count < or = 500/microL, for all symptomatic patients, and those with specific conditions and comorbidities. Therapy should be considered for asymptomatic patients with CD4 cell count > 500/microL. Components of the initial and subsequent regimens must be individualized, particularly in the context of concurrent conditions. Patients receiving antiretroviral treatment should be monitored regularly; treatment failure should be detected and managed early, with the goal of therapy, even in heavily pretreated patients, being HIV-1 RNA suppression below commercially available assay quantification limits.


Assuntos
Antirretrovirais/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1 , Adulto , Antirretrovirais/efeitos adversos , Contagem de Linfócito CD4 , Esquema de Medicação , Humanos , RNA Viral/sangue , Falha de Tratamento , Carga Viral
20.
Transgend Health ; 5(2): 116-121, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32656354

RESUMO

Purpose: To lower the HIV risk of transgender women, it is imperative to understand their unique HIV prevention needs and design biomedical prevention interventions that are responsive to the psychosocial, behavioral, and clinical needs of these communities. Preventive HIV vaccines are an important modality under investigation in diverse study participants. We sought to assess the knowledge of HIV vaccine research and the most common barriers and facilitators to participation in HIV vaccine studies among HIV-negative transgender women living in New York City. Methods: Six focus groups were conducted among 29 participants recruited in the New York City tri-state area from December 2014 to July 2015. Prefocus group quantitative questionnaire assessed demographic, behavioral information, knowledge of preventive vaccine research, and reasons for potential participation in prevention studies. Results: Median age of participants was 29 years and 41.4% identified as white. Over half of participants have heard of preventive vaccine research and majority indicated that an important factor in participating in HIV prevention research is to help the community collective effort. Key barriers that emerged were fear of side effects, feelings of exclusion from biomedical research. Facilitators to participation in prevention studies included trusting relationships with providers. Conclusions: These barriers and facilitators are important to consider in the design of studies inclusive of trans communities and transgender-specific prevention strategies. Barriers may be overcome by disseminating accurate information via social media or health providers.

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