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1.
Antimicrob Agents Chemother ; 66(11): e0081622, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36255254

RESUMO

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. MTN-033, a single site, open label, sequence randomized, crossover study, enrolled HIV-negative men to receive 0.05% DPV gel intrarectally using an applicator (2.5 g) and self-administered on an artificial phallus as lubricant (up to 10 g). The study evaluated the pharmacokinetics (in plasma, rectal fluid, and mucosal rectal tissue), safety, acceptability, and pharmacodynamics of DPV gel when applied rectally. Statistical comparisons between methods of application were performed using mixed effects models or Wilcoxon's signed rank tests. Sixteen participants used DPV gel by applicator and 15/16 participants used gel as lubricant (mean, 1.8 g; SD, 0.8). DPV plasma AUC0-24h after use as lubricant was estimated to be 0.41 times the AUC0-24h (95% CI 0.24, 0.88) after use with applicator. While DPV was quantifiable in plasma and luminal fluid, it was not quantifiable in tissue for both applicator and as lubricant administration. No related adverse events (AE) were reported, and 15/15 participants felt the gel was easy to use. Evidence of local delivery and systemic absorption of DPV when dosed as an anal lubricant supports the feasibility and potential for development of lubricant-delivered rectal microbicides. There were no safety concerns associated with use of DPV gel and participants reported finding it easy to use. However, lower DPV exposure in plasma and lack of quantifiable DPV in rectal tissue indicate that higher potency, concentration, and longer half-life antiretrovirals with optimized formulations will be needed to achieve protective tissue concentrations.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Humanos , Masculino , Feminino , Lubrificantes/uso terapêutico , Estudos Cross-Over , Pirimidinas/farmacocinética , Inibidores da Transcriptase Reversa/uso terapêutico , Géis , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle
2.
Sex Transm Infect ; 98(1): 32-37, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33542153

RESUMO

OBJECTIVES: Participation in HIV prevention trials could trigger risk compensation among participants. We evaluated potential risk compensation following use of a vaginal ring microbicide by women in a phase III trial in southwestern Uganda. METHODS: We used markers of sexual risk behaviour documented on standardised questionnaires, tested for STIs at baseline and quarterly for 2 years. Risk compensation was defined as a significant increase (trend p<0.05) in the proportion of women reporting risky sexual behaviour or a diagnosed STI between baseline and end of follow-up. RESULTS: Between September 2013 and December 2016, 197 women (active arm: n=132 and placebo: n=65) were enrolled at the Masaka site. There were decreases in all markers of sexual risk behaviour with statistically significant decreases in only the proportion of women reporting ≥2 sexual partners, p=0.026 and those diagnosed with Trichomonas vaginalis p<0.001 and or Neisseria gonorrhoeae p<0.001 CONCLUSIONS: No evidence of risk compensation was observed in this trial. TRIAL REGISTRATION NUMBER: NCT01539226.


Assuntos
Fármacos Anti-HIV/farmacologia , Dispositivos Anticoncepcionais Femininos/normas , Infecções por HIV/prevenção & controle , Pirimidinas/farmacologia , Adulto , Feminino , Humanos , Fatores de Risco , Comportamento Sexual , Adulto Jovem
3.
AIDS Behav ; 26(5): 1333-1346, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34657218

RESUMO

This study describes the acceptability of a rectal microbicide gel formulation using dapivirine (DPV) among men and women from two countries (United States and Thailand) participating in the Microbicide Trials Network-026 trial. We evaluated participants' acceptability of a rectal DPV/placebo gel as part of a Phase I trial (N = 26; 18 male, 8 female). Participants reported favorable acceptability of the study gel, with most participants reporting that they liked the gel the same (n = 14; 53.8%) or more (n = 11; 42.4%) than when they started the trial. Over half of participants noted that they would prefer the gel over condoms (n = 13; 50%) or that they liked condoms and the gel equally (n = 8; 30.8%). Side effects across products included leakage (n = 8; 30.8%), diarrhea (n = 4; 15.4%), or soiling (n = 1; 3.8%). The high acceptability of a rectal gel underscores its promise as a short-acting biomedical prevention, warranting future research for HIV prevention.Trial Registration: NCT03239483.


RESUMEN: Este estudio describe la aceptabilidad de un microbicida rectal (RM) con dapivirina (DPV) formulado como un gel por hombres y mujeres de dos países (Estados Unidos y Tailandia) que participaron como parte del Microbicide Trials Network (MTN)-026. Evaluamos la aceptabilidad de un gel rectal de DPV y un placebo como parte de un estudio de Fase I (N = 26; 18 hombres, 8 mujeres). Los participants informaron una aceptabilidad favorable sobre el gel del estudio; la mayoría de los participantes informaron que les gustó el gel igual (n = 14; 53.8%) o más (n = 11; 42.4%) que cuando comenzaron el estudio. Más de la mitad de los participantes señalaron que preferirían el gel sobre los condones (n = 13; 50%) o que les gustaban los condones y el gel por igual (n = 8; 30,8%). Los efectos de los productos incluyeron fugas (n = 8; 30,8%), diarrea (n = 4; 15,4%) o ensuciamiento (n = 1; 3,8%). La alta aceptabilidad de un gel rectal enfatiza su promesa para la prevención biomédica de acción corta y justifica futuras investigaciones para la prevención del VIH.


Assuntos
Anti-Infecciosos , Infecções por HIV , HIV-1 , Adulto , Anti-Infecciosos/uso terapêutico , Feminino , Géis , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Masculino , Pirimidinas , Estados Unidos
4.
AAPS PharmSciTech ; 23(7): 234, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002705

RESUMO

In response to an urgent need for advanced formulations for the delivery of anti-retrovirals, a stimuli-sensitive hydrogel formulation that intravaginally delivers HIV-1 entry inhibitor upon being exposed to a specific protease was developed. The hydrogel formulation consists of PEG-azide and PEG-DBCO covalently linked to the entry inhibitor peptide, enfuvirtide, via substrate linker that is designed to undergo proteolysis by prostate specific antigen (PSA) present in seminal fluid and release innate enfuvirtide. Of the tested PSA substrate linkers (HSSKLQYY, GISSFYSSK, AYLMYY, and AYLMGRR), HSSKLQ was found to be an optimal candidate for PEG-based hydrogel with kcat/KM of 2.2 M-1 s-1. The PEG-based hydrogel displayed a pseudoplastic, thixotropic behavior with overall viscosity varying between 1516 and 2.2 Pa.s, within the biologically relevant shear rates of 0.01-100 s-1. It also exhibited viscoelastic properties appropriate for uniform spreading and being retained in vagina. PEG-based hydrogels were loaded with N3-HSSKLQ-enfuvirtide (HF42) that is customarily synthesized enfuvirtide prodrug with its N-terminus connected to HSSKLQ linker. The stimuli-sensitive PEG-based hydrogel formulations upon being exposed to PSA released 36.5 ± 4.8% of enfuvirtide over 24 h in human ejaculate mimic of vaginal simulant fluid and seminal simulant fluid mixed in 1:3 ratio, which is significantly greater than its IC50. The PEG-based hydrogel was non-cytotoxic to both vaginal epithelial cells (VK2/E6E7) and murine macrophages (RAW 264.7) and did not significantly induce the production of nitric oxide, an inflammatory mediator. The PEG-based hydrogel is found to have suitable physicochemical properties for an intravaginal formulation of the PSA substrate-linked anti-retrovirals and is safe towards vaginal epithelium. It is capable of delivering enfuvirtide with effective concentrations to prevent women from HIV-1 infection.


Assuntos
Antirretrovirais , Hidrogéis , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Antirretrovirais/química , Antirretrovirais/farmacologia , Materiais Biocompatíveis , Enfuvirtida , Feminino , Humanos , Hidrogéis/química , Hidrogéis/uso terapêutico , Masculino , Camundongos , Peptídeos , Polietilenoglicóis/química , Antígeno Prostático Específico
5.
J Infect Dis ; 224(12 Suppl 2): S152-S160, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34396408

RESUMO

Murine models of Neisseria gonorrhoeae lower reproductive tract infection are valuable systems for studying N. gonorrhoeae adaptation to the female host and immune responses to infection. These models have also accelerated preclinical testing of candidate therapeutic and prophylactic products against gonorrhea. However, because N. gonorrhoeae infection is restricted to the murine cervicovaginal region, there is a need for an in vivo system for translational work on N. gonorrhoeae pelvic inflammatory disease (PID). Here we discuss the need for well-characterized preclinical upper reproductive tract infection models for developing candidate products against N. gonorrhoeae PID, and report a refinement of the gonorrhea mouse model that supports sustained upper reproductive tract infection. To establish this new model for vaccine testing, we also tested the licensed meningococcal 4CMenB vaccine, which cross-protects against murine N. gonorrhoeae lower reproductive tract infection, for efficacy against N. gonorrhoeae in the endometrium and oviducts following transcervical or vaginal challenge.


Assuntos
Anti-Infecciosos/administração & dosagem , Gonorreia/prevenção & controle , Doença Inflamatória Pélvica/prevenção & controle , Infecções do Sistema Genital/microbiologia , Animais , Modelos Animais de Doenças , Feminino , Gonorreia/tratamento farmacológico , Camundongos , Neisseria gonorrhoeae/imunologia , Doença Inflamatória Pélvica/microbiologia
6.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32102878

RESUMO

Semen is the primary transmission vehicle for various pathogenic viruses. Initial steps of transmission, including cell attachment and entry, likely occur in the presence of semen. However, the unstable nature of human seminal plasma and its toxic effects on cells in culture limit the ability to study in vitro virus infection and inhibition in this medium. We found that whole semen significantly reduces the potency of antibodies and microbicides that target glycans on the envelope glycoproteins (Envs) of HIV-1. The extraordinarily high concentration of the monosaccharide fructose in semen contributes significantly to the effect by competitively inhibiting the binding of ligands to α1,2-linked mannose residues on Env. Infection and inhibition in whole human seminal plasma are accurately mimicked by a stable synthetic simulant of seminal fluid that we formulated. Our findings indicate that, in addition to the protein content of biological secretions, their small-solute composition impacts the potency of antiviral microbicides and mucosal antibodies.IMPORTANCE Biological secretions allow viruses to spread between individuals. Each type of secretion has a unique composition of proteins, salts, and sugars, which can affect the infectivity potential of the virus and inhibition of this process. Here, we describe HIV-1 infection and inhibition in whole human seminal plasma and a synthetic simulant that we formulated. We discovered that the sugar fructose in semen decreases the activity of a broad and potent class of antiviral agents that target mannose sugars on the envelope protein of HIV-1. This effect of semen fructose likely reduces the efficacy of such inhibitors to prevent the sexual transmission of HIV-1. Our findings suggest that the preclinical evaluation of microbicides and vaccine-elicited antibodies will be improved by their in vitro assessment in synthetic formulations that simulate the effects of semen on HIV-1 infection and inhibition.


Assuntos
Frutose/metabolismo , Frutose/farmacologia , Sêmen/metabolismo , Adulto , Anti-Infecciosos/farmacologia , Antivirais/antagonistas & inibidores , Antivirais/farmacologia , Linhagem Celular Tumoral , Produtos do Gene env/metabolismo , Genes env/genética , Células HEK293 , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Masculino , Manose/metabolismo , Polissacarídeos/imunologia , Polissacarídeos/metabolismo , Sêmen/virologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
7.
AIDS Behav ; 25(9): 2992-3010, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33977356

RESUMO

Despite clinicians consistently advising against vaginal douching, 29-92% of women worldwide report douching. This review documents women's douching practices, motivations for douching, and specific associations (or absence of associations) between vaginal douche use and vaginal outcomes thought to be associated with douching. Understanding women's existing douching behaviors and vaginal health outcomes is critical for developing a safe vaginal microbicide douche that can be used as HIV pre-exposure prophylaxis (PrEP). A vaginal douche as PrEP could help prevent new HIV infections, since emerging evidence shows some women discontinue oral PrEP. We performed a systematic review of the literature using the guidelines for Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). Articles included in the analysis (N = 48) were published 2009-2019 in English and focused on women's experiences with douching. Two trained independent reviewers assessed these articles for content on vaginal douching, including racial/ethnic focus of studies, study design, sampling, women's reasons for douching, contents of douche solutions, and associations between vaginal douching and vaginal health outcomes. Several studies focused on Black women (N = 12 studies) or had no racial/ethnic focus (N = 12). Just over half of all studies (N = 24) were cross-sectional and involved a self-reported questionnaire and lab samples. Studies sampled women from health clinics where they were (N = 13) or were not (N = 14) presenting for vaginal health complaints. Women's primary motivation for douching was for "general cleanliness" (N = 13), and most douche solutions contained water (N = 12). There was little empirical agreement between vaginal douche use and most vaginal health outcomes. Future studies of PrEP vaginal douches should be well controlled and prioritize safety to ensure positive vaginal health outcomes.


Assuntos
Anti-Infecciosos , Infecções por HIV , Profilaxia Pré-Exposição , Estudos Transversais , Feminino , Infecções por HIV/prevenção & controle , Humanos , Ducha Vaginal/efeitos adversos
8.
AIDS Behav ; 25(3): 721-731, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32920652

RESUMO

Discrepancies between self-reported and actual adherence to biomedical HIV interventions is common and in clinical trials can compromise the integrity of findings. One solution is to monitor adherence biomarkers, but it is not well understood how to navigate biomarker feedback with participants. We surveyed 42 counselors and interviewed a subset of 22 to characterize their perspectives about communicating with participants about residual drug levels, an objective marker of adherence, within MTN-025/HOPE, a Phase 3b clinical trial of a vaginal ring to prevent HIV. When biomarkers indicated low drug levels that mismatched high adherence by self-report, counselors encountered barriers to acceptance and comprehension among participants. However, discrepancies between low self-report and higher drug levels generally stimulated candor. Women recollected times they had not used the product and disclosed problems that counselors thought might otherwise have remained forgotten or concealed. Navigating conversations toward HIV prevention was easier at mid-range drug levels and when women indicated motivation to prevent HIV. Ratings of residual drug level offered a somewhat objective measure of adherence and protection that counselors perceived as meaningful to participants and as a valuable catalyst for broaching conversation about HIV prevention. However, communication about drug levels required that counselors navigate emotional barriers, respond skillfully to questions about accuracy, and pivot conversations non-judgmentally away from numerical results and toward the priority of HIV prevention. Findings suggest a role for biomarker feedback in future clinical trials as well as other clinical contexts where biomarkers may be monitored, to motivate disclosure of actual adherence and movement toward HIV prevention.Clinical Trial Number NCT02858037.


RESUMEN: Discrepancias entre la adherencia auto-reportada y la verdadera a intervenciones biomédicas de VIH pueden comprometer los ensayos clínicos. Una solución es monitorear la adherencia por medio de ensayos biológicos, pero no se entiende bien cómo comunicar estas medidas a los participantes. En MTN-025/HOPE, un ensayo fase 3b de un anillo vaginal para prevenir VIH, encuestamos a 42 consejeros de adherencia y entrevistamos a un subconjunto de 22 para caracterizar sus perspectivas sobre comunicar una medida objetiva de adherencia al anillo, el nivel residual de droga (RDL por sus siglas en inglés). Los consejeros reportaron que los participantes apreciaron la retroalimentación del RDL como una indicación de su protección de VIH. Niveles más altos de droga estimularon euforia y alivio mientras niveles mas bajos resultaron en desilusión. Una postura no crítica y el apoyo a la autonomía de elegir otras alternativas al anillo promovieron divulgación de las razones por la falta de adherencia. Hablar del monitoreo de RDL como "protección" en vez de "adherencia" ayudó a cambiar el enfoque desde resultados numéricos hasta la meta mayor del ensayo de prevenir el VIH. Personalizar la retroalimentación de medidas objetivas de adherencia requiere una conversación cuidadosa para minimizar las actitudes defensivas. La retroalimentación personalizada también se puede implementar de forma que motive la divulgación de la falta de adherencia y evoque un compromiso a prácticas de prevención. Enfatizar las motivaciones de las mujeres a prevenir el VIH, en vez de los resultados numéricos, puede incentivar a los usuarios consistentes a continuar y a los usuarios inconsistentes a usar métodos alternativos de prevención.


Assuntos
Anti-Infecciosos/administração & dosagem , Infecções por HIV/prevenção & controle , Administração Intravaginal , Adulto , Anti-Infecciosos/uso terapêutico , Ensaios Clínicos como Assunto , Feminino , Humanos , Adesão à Medicação/psicologia , Motivação , Aceitação pelo Paciente de Cuidados de Saúde , Preparações Farmacêuticas , Cremes, Espumas e Géis Vaginais/uso terapêutico
9.
BMC Womens Health ; 21(1): 126, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33766006

RESUMO

BACKGROUND: Women may need or seek male partner approval to safely and consistently use oral antiretroviral pre-exposure prophylaxis (PrEP) or vaginal microbicides. We developed CHARISMA, a counseling intervention to support women's relationships and their ability to consistently use HIV prevention products. METHODS: In a pilot study with 95 female participants in Johannesburg, South Africa, lay counselors implemented CHARISMA, assessing participants' relationship(s) with their male partner(s) and barriers or facilitators to HIV prevention method use, and then providing tailored, interactive counseling. We conducted study participant surveys and clinic staff interviews to evaluate CHARISMA's feasibility and acceptability. RESULTS: The CHARISMA pilot study indicates that a two-session relationship counseling intervention with 6-month follow-up to support women's ability to safely and effectively use vaginal microbicides was generally acceptable and feasible. Most participants thought CHARISMA was relevant, helpful, and about the right length, and that it had a positive impact on their relationships with their partners and their product use. Staff estimated that the intervention took 1.5-2 h to implement at enrollment and 45 min to an hour for the month 1 visit. They thought that overall CHARISMA was generally feasible to implement. CONCLUSIONS: Findings from this study suggest several lessons learned that may be relevant to others developing interventions supporting women's use of oral PrEP or vaginal microbicides. The use of lay counselors instead of nurses to deliver counseling appeared to be successful, but the counselors experienced significant stress from hearing about participants' traumatic experiences and required emotional support to avoid burnout. Although staff and participants felt that having multiple intervention sessions over time was valuable, a similar level of intensity may not be feasible in other settings. Further research is needed to determine an intervention delivery mode and follow-up period that optimally balances participant needs and clinic resources. Male engagement was a challenge, as it has been in previous studies of vaginal microbicides. Alternative strategies to reach men that do not require them to come to the clinic or rely on their female partners may be more effective.


Assuntos
Infecções por HIV , Aconselhamento , Estudos de Viabilidade , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Projetos Piloto , Parceiros Sexuais , África do Sul
10.
BMC Public Health ; 21(1): 2041, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749675

RESUMO

BACKGROUND: Low adherence to investigational products can negatively impact study outcomes, limiting the ability to demonstrate efficacy. To continue advancing potential new HIV prevention technologies, efforts are needed to improve adherence among study participants. In MTN-020/ASPIRE, a phase III randomized, double-blind, placebo-controlled study of the dapivirine vaginal ring carried out across 15 sites in sub-Saharan Africa, a multifaceted approach to adherence support was implemented, including a strong focus on participant engagement activities (PEAs). In this manuscript, we describe PEAs and participant attendance, and analyze the potential impact of PEAs on ring use. METHODS: All sites implemented PEAs and submitted activity and attendance reports to the study management team throughout the study. Participant demographics were collected via case report forms. Residual dapivirine remaining in the last ring returned by each participant was used to estimate drug released from the ring, which was then adjusted for time participants had the ring to calculate probable use categorized into three levels (low/intermittent/high). Product use was connected to PEA attendance using participant identification numbers. We used multivariate Poisson regression with robust standard errors to explore differences in ring use between PEA attendance groups and reviewed qualitative reports for illustrative quotes highlighting participant experiences with PEAs. RESULTS: 2312 of 2629 study participants attended at least one of 389 PEAs conducted across sites. Participant country and partner knowledge of study participation were most strongly associated with PEA attendance (p < 0.005) with age, education, and income status also associated with event attendance (p < 0.05). When controlling for these variables, participants who attended at least one event were more likely to return a last ring showing at least some use (RR = 1.40) than those who never attended an event. There was a stronger correlation between a last returned ring showing use and participant attendance at multiple events (RR = 1.52). CONCLUSIONS: Our analysis supports the growing body of work illustrating the importance of meaningfully engaging research participants to achieve study success and aligns with other analyses of adherence support efforts during ASPIRE. While causation between PEA attendance and product use cannot be established, residual drug levels in returned rings strongly correlated with participant attendance at PEAs, and the benefits of incorporating PEAs should be considered when designing future studies of investigational products.


Assuntos
Fármacos Anti-HIV , Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Pirimidinas
11.
Proc Natl Acad Sci U S A ; 115(33): E7854-E7862, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30061386

RESUMO

The transmission of HIV can be prevented by the application of neutralizing monoclonal antibodies and lectins. Traditional recombinant protein manufacturing platforms lack sufficient capacity and are too expensive for developing countries, which suffer the greatest disease burden. Plants offer an inexpensive and scalable alternative manufacturing platform that can produce multiple components in a single plant, which is important because multiple components are required to avoid the rapid emergence of HIV-1 strains resistant to single microbicides. Furthermore, crude extracts can be used directly for prophylaxis to avoid the massive costs of downstream processing and purification. We investigated whether rice could simultaneously produce three functional HIV-neutralizing proteins (the monoclonal antibody 2G12, and the lectins griffithsin and cyanovirin-N). Preliminary in vitro tests showed that the cocktail of three proteins bound to gp120 and achieved HIV-1 neutralization. Remarkably, when we mixed the components with crude extracts of wild-type rice endosperm, we observed enhanced binding to gp120 in vitro and synergistic neutralization when all three components were present. Extracts of transgenic plants expressing all three proteins also showed enhanced in vitro binding to gp120 and synergistic HIV-1 neutralization. Fractionation of the rice extracts suggested that the enhanced gp120 binding was dependent on rice proteins, primarily the globulin fraction. Therefore, the production of HIV-1 microbicides in rice may not only reduce costs compared to traditional platforms but may also provide functional benefits in terms of microbicidal potency.


Assuntos
Fármacos Anti-HIV , Anticorpos Monoclonais , Endosperma , Anticorpos Anti-HIV , Proteína gp120 do Envelope de HIV/antagonistas & inibidores , HIV-1/química , Oryza , Plantas Geneticamente Modificadas , Fármacos Anti-HIV/química , Fármacos Anti-HIV/metabolismo , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Endosperma/química , Endosperma/genética , Endosperma/metabolismo , Anticorpos Anti-HIV/biossíntese , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/genética , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/metabolismo , Oryza/química , Oryza/genética , Oryza/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
12.
Mol Pharm ; 17(3): 852-864, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32017579

RESUMO

Clinical trials have demonstrated partial protection against HIV-1 infection by vaginal microbicide formulations based on antiretroviral (ARV) drugs. Improved formulations that will maintain sustained drug concentrations at viral target sites in the cervicovaginal mucosa are needed. We have previously demonstrated that treatment of cervicovaginal cell lines with ARV drugs can alter gene expression of drug transporters, suggesting that the mucosal disposition of ARV drugs delivered vaginally can be modulated by drug transporters. This study aimed to investigate in vivo modulation of drug transporter expression in a nonhuman primate model by tenofovir and darunavir released from film formulations. Cervicovaginal tissues were collected from drug-naïve macaques and from macaques vaginally treated with film formulations of tenofovir or darunavir. Drug release in vaginal fluid as well as drug absorption in cervicovaginal tissues and lymph nodes were verified by mass spectrometry. The effects of exposure to drugs on the expression of transporters relevant to ARV drugs were evaluated by quantitative PCR. We showed expression in cervicovaginal tissue of drug-naïve macaques of transporters important for distribution of ARV drugs, albeit at lower levels compared to human tissue for key transporters including P-glycoprotein. Concentrations of tenofovir and darunavir well above the EC50 values determined in vitro were detected in vaginal fluid and vaginal tissues of macaques treated with drug-dissolving films over 24 h and were also comparable to those shown previously to modulate drug transporter expression. Accordingly, Multidrug Resistance associated Protein 2 (MRP2) in cervicovaginal tissue was upregulated by both tenofovir and darunavir. The two drugs also differentially induced and/or inhibited expression of key uptake transporters for reverse transcriptase inhibitors and protease inhibitors. The lower expression of key transporters in macaques may result in increased retention of ARV drugs at the simian cervicovaginal mucosa compared to the human mucosa and has implications for translation of preclinical data. Modulation of drug transporter expression by tenofovir and darunavir points to the potential benefit of MRP2 inhibition to increase ARV drug penetration through the cervicovaginal epithelium.


Assuntos
Darunavir/farmacocinética , Composição de Medicamentos/métodos , Infecções por HIV/prevenção & controle , Inibidores da Protease de HIV/farmacocinética , HIV-1 , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Tenofovir/farmacocinética , Regulação para Cima/efeitos dos fármacos , Vagina/metabolismo , Administração Intravaginal , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Darunavir/administração & dosagem , Modelos Animais de Doenças , Feminino , Infecções por HIV/virologia , Inibidores da Protease de HIV/administração & dosagem , Humanos , Macaca fascicularis , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Tenofovir/administração & dosagem , Distribuição Tecidual
13.
AIDS Behav ; 24(2): 637-647, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31254190

RESUMO

INTRODUCTION: Incorporating end-user input into the design of new vaginal microbicides for women is key to optimizing their uptake, consistent use, and, ultimately, success in combatting the heterosexual HIV epidemic. METHODS: The Quatro Study assessed four placebo forms of vaginally inserted HIV-microbicides among young microbicide-naïve African women: on-demand film, insert and gel, and monthly ring. Participants randomly used each product for 1 month and provided product satisfaction ratings (1-5 scale), and opinions on product attributes and potential alternative designs. Qualitative data were collected through focus group discussions at study exit. Multivariable associations between attribute opinions and overall product rating were examined using Poisson regression models with robust standard errors to assess the attributes most influential to satisfaction. RESULTS: Overall opinions of products and their individual attributes were generally positive; all products were rated either 4 or a 5 by ≥ 50% of participants. Attributes related to ease of use and interference with normal activities were the most salient predictors of satisfaction. Preferences for duration of use tended toward relatively shorter use periods for the ring (i.e., 1-3 months vs. 12 months) and for coitally independent dosing for the on-demand products. CONCLUSIONS: How well a product fit in with participants' lifestyles was important to their overall satisfaction. For on-demand products, greater flexibility around timing of use was desired, to avoid coital dependency of the dosing.


Assuntos
Anti-Infecciosos/administração & dosagem , População Negra/psicologia , Anticoncepção/métodos , Anticoncepcionais/administração & dosagem , Infecções por HIV/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde , Profilaxia Pré-Exposição/métodos , Infecções Sexualmente Transmissíveis/prevenção & controle , Cremes, Espumas e Géis Vaginais/uso terapêutico , Administração Intravaginal , Adulto , Coito , Estudos Cross-Over , Feminino , Grupos Focais , Infecções por HIV/tratamento farmacológico , Humanos , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Pesquisa Qualitativa , Adulto Jovem
14.
AIDS Behav ; 24(5): 1432-1442, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31667678

RESUMO

Although vaginal microbicides for HIV prevention are designed to be female-initiated, male partner influence has been identified as one of the most significant factors impacting women's willingness and ability to use them. As a result, research teams have sought to increase male partner involvement by encouraging disclosure of product use to male partners, promoting male partner engagement in the study through attendance at the study clinic, and helping women to garner male partner support for product use. This paper aims to assess the impact of these three elements of male partner involvement on women's adherence to the dapivirine vaginal ring during MTN-020/ASPIRE, a phase III randomized placebo-controlled clinical trial involving 2629 women in Malawi, South Africa, Uganda, and Zimbabwe. During the study, 64-80% of participants reported disclosure of ring use at each quarterly visit, and 13% reported that their partners had attended the study clinic at some point during the study. At study exit, 66% reported that their partner was supportive, 18% unsupportive, and 17% were unsure. After adjusting for age, site and time in study, women were more likely to have low ring adherence if they had an unsupportive male partner (aRR 1.29, 95% CI 1.03-1.62). Neither disclosure nor clinic attendance directly predicted ring adherence, but disclosure increased the probability of having a supportive partner (aRRR 24.17, 95% CI 16.38-35.66) or an unsupportive partner (aRRR 4.10, 95% CI 2.70-6.24), relative to an unknown level of partner support. Women were also more likely to have a supportive partner if their partner had attended the clinic (aRRR 3.77, 95% CI 1.36-10.42). This study suggests that although the vaginal ring is relatively discreet, lack of support from male partners remains a relevant barrier to use. Though both disclosure and clinic attendance may increase partner support, disclosure may also increase partner opposition. Interventions to reduce male partner opposition are needed to maximize the potential impact of the ring and other PrEP products for HIV prevention.


Assuntos
Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Malaui , Masculino , Pirimidinas , África do Sul , Uganda , Adulto Jovem , Zimbábue
15.
AIDS Behav ; 24(8): 2387-2399, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31980993

RESUMO

Women are disproportionately at risk of acquiring HIV in East and Southern Africa, despite global declines in incidence. Female-initiated HIV prevention methods, like the dapivirine vaginal ring, are needed to end the HIV epidemic. In-depth interviews and focus groups retrospectively explored peer influence on acceptability of and adherence to the ring during the ASPIRE trial, a phase III placebo-controlled trial. Results were analyzed using an inductive analytic approach. Study participants (peers) of all ages and adherence groups developed important interpersonal connections and reported being more open and honest with each other than with external peers or study staff. Study peers who knew each other prior to joining appeared to have a stronger influence on each other's adherence than peers who met in the study. External peers provided primarily negative input about the ring and study, which sometimes led to ring removals. Peers' influence on each other's behavior in both prosocial and detrimental manners could have repercussions on adherence to a biomedical intervention, and consequently, individual disease risk and clinical trial outcomes. Future ring demonstration and implementation studies could use peer networks to intentionally influence uptake and adherence to the ring.


Assuntos
Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Pirimidinas/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Influência dos Pares , Estudos Retrospectivos
16.
Mar Drugs ; 18(9)2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32825645

RESUMO

Different kinds of red algae are enriched with chemically diverse carbohydrates. In particular, a group of sulfated polysaccharides, which were isolated from the cell walls of red algae, gained a large amount of attention due to their broad-spectrum antimicrobial activities. Within that group, carrageenans (CGs) were expected to be the first clinically applicable microbicides that could prevent various viral infections due to their superior antiviral potency and desirable safety profiles in subclinical studies. However, their anticipated beneficial effects could not be validated in human studies. To assess the value of a second attempt at pharmacologically developing CGs as a new class of preventive microbicides, all preclinical and clinical development processes of CG-based microbicides need to be thoroughly re-evaluated. In this review, the in vitro toxicities; in vivo safety profiles; and in vitro, ex vivo, and in vivo antiviral activities of CGs are summarized according to the study volume of their target viruses, which include human immunodeficiency virus, herpesviruses, respiratory viruses, human papillomavirus, dengue virus, and other viruses along with a description of their antiviral modes of action and development of antiviral resistance. This evaluation of the strengths and weaknesses of CGs will help provide future research directions that may lead to the successful development of CG-based antimicrobial prophylactics.


Assuntos
Antivirais/uso terapêutico , Carragenina/uso terapêutico , Rodófitas/química , Viroses/tratamento farmacológico , Animais , Antivirais/efeitos adversos , Antivirais/isolamento & purificação , Carragenina/efeitos adversos , Carragenina/isolamento & purificação , Interações Hospedeiro-Patógeno , Humanos , Viroses/virologia
17.
Cult Health Sex ; 22(6): 660-674, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31241426

RESUMO

Men desire to be involved in their partner's decision-making about vaginal microbicide use. This coincides with women's desire to inform male partners about their microbicide use. Educating men about microbicides may enhance acceptability and generate critical support for the female participants of microbicide trials. In this multiphase mixed-methods study, we adapted an educational intervention on vaginal microbicides and tested it among men (n = 45) to determine its effect on men's knowledge regarding HIV/STI, vaginal microbicides and microbicide trials. We also conducted focus group discussions (FGDs) with the female partners (K = 3, n = 43) of the study participants and community representatives (K = 2, n = 24) to obtain their views on male partner microbicide education. We analysed FGD data for key themes using content analysis. HIV and vaginal microbicide knowledge scores increased significantly among men after the educational intervention. Both women and men highly supported male partner microbicide education, in the context of existing gender relations, to increase men's understanding about microbicides, promote adherence and help women gain their partners' trust. Complex gender dynamics should be considered when designing male partner educational interventions to improve acceptability and the use of microbicides and other female-initiated HIV prevention methods.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Anti-Infecciosos/uso terapêutico , Comportamento Contraceptivo/psicologia , Infecções por HIV/prevenção & controle , Educação em Saúde/métodos , Cremes, Espumas e Géis Vaginais/uso terapêutico , Administração Intravaginal , Adulto , Feminino , Humanos , Quênia , Masculino , Parceiros Sexuais/psicologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Inquéritos e Questionários
18.
AIDS Behav ; 23(6): 1484-1493, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30415431

RESUMO

Tenofovir administration via rectal douching results in higher rectal-mucosa drug concentration than oral administration. Many who engage in receptive anal intercourse (RAI) use cleansing rectal douches. To inform development of a behaviorally-congruent tenofovir douche, 4751 individuals ≥ 18 years-old, born male, from all US states/territories, who engaged in anal intercourse responded to an online survey. Of those who reported RAI in the prior 3 months, 80% douched beforehand, 82% within 1 h, mean 2.9 consecutive applications; 27% douched afterwards, 83% within 1 h, mean 1.7 consecutive applications. Among multidose users, 78% applied doses within 2 min, and 76% retained liquid < 1 min. Most used tap water (89%) in an enema bottle (50%) or rubber bulb (43%), and douched for cleanliness (97%), to avoid smelling bad (65%), and to enhance pleasure (24%). 98% reported high likelihood of using an HIV-prevention douche. An ideal product will protect within a user's typical number of applications, within 1 h, and be dissolvable in tap water.


Assuntos
Anti-Infecciosos/administração & dosagem , Infecções por HIV/prevenção & controle , Reto/efeitos dos fármacos , Minorias Sexuais e de Gênero , Tenofovir/administração & dosagem , Irrigação Terapêutica/métodos , Administração Retal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Infecciosos/farmacologia , Feminino , Inquéritos Epidemiológicos , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Reto/imunologia , Tenofovir/farmacologia , Irrigação Terapêutica/estatística & dados numéricos , Estados Unidos , Adulto Jovem
19.
AIDS Behav ; 23(2): 504-512, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30218318

RESUMO

This analysis compares self-reports of product use with objective measures of non-adherence-quarterly plasma dapivirine levels and monthly residual dapivirine (DPV) levels in used rings-in MTN-020/ASPIRE, a phase 3 trial of a monthly DPV vaginal ring among women aged 18-45 years in Malawi, South Africa, Uganda and Zimbabwe. For participants on active product (N = 1211) we assessed self-reported monthly non-adherence, as measured by (1) whether the ring was ever out, and out for ≥ 12 h in the previous month and, (2) by a self-rating scale assessing ability to keep the vaginal ring inserted, and compared the self-reports to two biomarkers of non-use separately and as a composite measure. For this analysis, a plasma DPV value ≤ 95 pg/ml and residual ring ≥ 23.5 mg were used to classify non-adherence (i.e. the ring never being in the vagina the previous month). Compared to self-reports, non-adherence was found to be substantially higher for the composite measure as well as its two components, an indication that ring removal was likely underreported in the trial. The discrepancy between the self-report measure of ring outage and the composite indicator was greater for those aged 18-21 than for those older, evidence that younger women are more likely to underreport non-adherence. Despite underreporting of non-adherence, self-reports of the ring never being out were significant in predicting the composite objective measure. Furthermore, the association between the self-rating scale and the objective measure was in the expected direction and significant, although 11% of those 18-21 and 7% of those 22+ who rated their ability to keep the ring inserted as good, very good or excellent in the 4 weeks prior to exit were considered non-adherent according to the objective measure. This analysis indicates that while self-reports are significantly associated with objective measures of adherence in the ASPIRE trial, they were inflated-more so by those younger-and therefore may have limited utility identifying those who have challenges using products as directed. ClinicalTrials.gov number NCT01617096.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Dispositivos Anticoncepcionais Femininos , Infecções por HIV/prevenção & controle , Cooperação do Paciente/estatística & dados numéricos , Pirimidinas/administração & dosagem , Autorrelato , Administração Intravaginal , Adulto , Feminino , Humanos , Malaui , África do Sul , Uganda , Adulto Jovem , Zimbábue
20.
AIDS Care ; 31(3): 379-387, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30318905

RESUMO

We examined product adherence among 187 men who have sex with men and transgender women enrolled in a phase II, crossover trial comparing safety and acceptability of an oral tablet and a rectal gel used daily for HIV prevention. Participants reported adherence via daily text messages during 8-week periods. Trajectory analysis identified weekly patterns. Polytomous logistic regression identified characteristics associated with higher probability of trajectory group membership. We identified 3 groups per product: high-adherers (72% daily oral, 70% daily gel); decreasing-adherers (20% daily oral, 22% daily gel); and low-adherers (8% daily oral, 9% daily gel). Daily oral high-adherers (compared with low-adherers) were more likely to self-identify as male (OR = 4.76, 95% CI:1.35-16.67), to have more sexual partners (OR = 1.67, 95% CI:1.04-2.63), and to find the tablet easy to swallow (OR = 2.22, 95% CI:1.08-4.76). Daily gel high-adherers (compared with low-adherers) were more likely to be older (OR = 1.16, 95% CI:1.05-1.28), to find gel application easier at the last few applications (OR = 2.27, 95% CI:1.01-5.00), and to report a change in routine if gel was not used (OR = 5.26, 95% CI:1.23-100.00). Characteristics of participants likely to be high-adherers to product use vary according to product. Evaluation of acceptability prior to phase II/III trials could identify participants likely to maintain high adherence.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/prevenção & controle , Adesão à Medicação/estatística & dados numéricos , Minorias Sexuais e de Gênero , Pessoas Transgênero , Administração Oral , Administração Retal , Adolescente , Adulto , Fármacos Anti-HIV/efeitos adversos , Estudos Cross-Over , Feminino , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Sexual , Parceiros Sexuais , Comprimidos , Adulto Jovem
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