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1.
J Infect Dis ; 229(4): 1158-1165, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38099506

RESUMO

BACKGROUND: Confounding introduced by individuals' sexual risk behavior is potentially a significant source of bias in HIV-1 prevention intervention studies. To more completely account for sexual behaviors when assessing the efficacy of the monthly dapivirine ring, a new longer-acting HIV-1 prevention option for women, we estimated per-sex-act risk reduction associated with product use. METHODS: We conducted a secondary analysis of data from MTN-020/ASPIRE, a phase 3, randomized, placebo-controlled efficacy trial of the dapivirine ring that recruited HIV-uninfected, African women aged 18-45 years. With cumulative sex acts as the time scale, we used multivariable Cox regression with inverse probability of censoring weights to estimate HIV-1 risk reduction associated with a rate of dapivirine release indicative of consistent product use. RESULTS: Women in the dapivirine ring group (n = 1187) had an estimated incidence rate of 2.3 (95% confidence interval [CI], 1.8-3.1) HIV-1 acquisition events per 10 000 sex acts versus 3.6 (95% CI, 2.9-4.4) per 10 000 acts in the placebo group (n = 1187). Dapivirine release indicative of consistent ring use was associated with a 63% (95% CI, 33%-80%) per-sex-act HIV-1 risk reduction. CONCLUSIONS: These results support the efficacy of the dapivirine vaginal ring for HIV-1 prevention and help to inform decision-making for women, providers, and policymakers regarding product use. CLINICAL TRIALS REGISTRATION: NCT01617096.


Assuntos
Fármacos Anti-HIV , Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Soropositividade para HIV , HIV-1 , Pirimidinas , Feminino , Humanos , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Comportamento de Redução do Risco , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade
2.
PLoS Med ; 21(3): e1004360, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38502656

RESUMO

BACKGROUND: Adjuvants are widely used to enhance and/or direct vaccine-induced immune responses yet rarely evaluated head-to-head. Our trial directly compared immune responses elicited by MF59 versus alum adjuvants in the RV144-like HIV vaccine regimen modified for the Southern African region. The RV144 trial of a recombinant canarypox vaccine vector expressing HIV env subtype B (ALVAC-HIV) prime followed by ALVAC-HIV plus a bivalent gp120 protein vaccine boost adjuvanted with alum is the only trial to have shown modest HIV vaccine efficacy. Data generated after RV144 suggested that use of MF59 adjuvant might allow lower protein doses to be used while maintaining robust immune responses. We evaluated safety and immunogenicity of an HIV recombinant canarypox vaccine vector expressing HIV env subtype C (ALVAC-HIV) prime followed by ALVAC-HIV plus a bivalent gp120 protein vaccine boost (gp120) adjuvanted with alum (ALVAC-HIV+gp120/alum) or MF59 (ALVAC-HIV+gp120/MF59) or unadjuvanted (ALVAC-HIV+gp120/no-adjuvant) and a regimen where ALVAC-HIV+gp120 adjuvanted with MF59 was used for the prime and boost (ALVAC-HIV+gp120/MF59 coadministration). METHODS AND FINDINGS: Between June 19, 2017 and June 14, 2018, 132 healthy adults without HIV in South Africa, Zimbabwe, and Mozambique were randomized to receive intramuscularly: (1) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/MF59 (months 3, 6, and 12), n = 36; (2) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/alum (months 3, 6, and 12), n = 36; (3) 4 doses of ALVAC-HIV+gp120/MF59 coadministered (months 0, 1, 6, and 12), n = 36; or (4) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/no adjuvant (months 3, 6, and 12), n = 24. Primary outcomes were safety and occurrence and mean fluorescence intensity (MFI) of vaccine-induced gp120-specific IgG and IgA binding antibodies at month 6.5. All vaccinations were safe and well-tolerated; increased alanine aminotransferase was the most frequent related adverse event, occurring in 2 (1.5%) participants (1 severe, 1 mild). At month 6.5, vaccine-specific gp120 IgG binding antibodies were detected in 100% of vaccinees for all 4 vaccine groups. No significant differences were seen in the occurrence and net MFI of vaccine-specific IgA responses between the ALVAC-HIV+gp120/MF59-prime-boost and ALVAC-HIV+gp120/alum-prime-boost groups or between the ALVAC-HIV+gp120/MF59-prime-boost and ALVAC-HIV+gp120/MF59 coadministration groups. Limitations were the relatively small sample size per group and lack of evaluation of higher gp120 doses. CONCLUSIONS: Although MF59 was expected to enhance immune responses, alum induced similar responses to MF59, suggesting that the choice between these adjuvants may not be critical for the ALVAC+gp120 regimen. TRIAL REGISTRATION: HVTN 107 was registered with the South African National Clinical Trials Registry (DOH-27-0715-4894) and ClinicalTrials.gov (NCT03284710).


Assuntos
Vacinas contra a AIDS , Compostos de Alúmen , Infecções por HIV , HIV-1 , Polissorbatos , Esqualeno , Adulto , Humanos , Adjuvantes Imunológicos , Vacinas contra a AIDS/efeitos adversos , Anticorpos Anti-HIV , Infecções por HIV/prevenção & controle , Imunogenicidade da Vacina , Imunoglobulina A , Imunoglobulina G , Vacinas Combinadas , Vacinas Sintéticas
3.
N Engl J Med ; 384(11): 1003-1014, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33730454

RESUMO

BACKGROUND: Whether a broadly neutralizing antibody (bnAb) can be used to prevent human immunodeficiency virus type 1 (HIV-1) acquisition is unclear. METHODS: We enrolled at-risk cisgender men and transgender persons in the Americas and Europe in the HVTN 704/HPTN 085 trial and at-risk women in sub-Saharan Africa in the HVTN 703/HPTN 081 trial. Participants were randomly assigned to receive, every 8 weeks, infusions of a bnAb (VRC01) at a dose of either 10 or 30 mg per kilogram (low-dose group and high-dose group, respectively) or placebo, for 10 infusions in total. HIV-1 testing was performed every 4 weeks. The VRC01 80% inhibitory concentration (IC80) of acquired isolates was measured with the TZM-bl assay. RESULTS: Adverse events were similar in number and severity among the treatment groups within each trial. Among the 2699 participants in HVTN 704/HPTN 085, HIV-1 infection occurred in 32 in the low-dose group, 28 in the high-dose group, and 38 in the placebo group. Among the 1924 participants in HVTN 703/HPTN 081, infection occurred in 28 in the low-dose group, 19 in the high-dose group, and 29 in the placebo group. The incidence of HIV-1 infection per 100 person-years in HVTN 704/HPTN 085 was 2.35 in the pooled VRC01 groups and 2.98 in the placebo group (estimated prevention efficacy, 26.6%; 95% confidence interval [CI], -11.7 to 51.8; P = 0.15), and the incidence per 100 person-years in HVTN 703/HPTN 081 was 2.49 in the pooled VRC01 groups and 3.10 in the placebo group (estimated prevention efficacy, 8.8%; 95% CI, -45.1 to 42.6; P = 0.70). In prespecified analyses pooling data across the trials, the incidence of infection with VRC01-sensitive isolates (IC80 <1 µg per milliliter) per 100 person-years was 0.20 among VRC01 recipients and 0.86 among placebo recipients (estimated prevention efficacy, 75.4%; 95% CI, 45.5 to 88.9). The prevention efficacy against sensitive isolates was similar for each VRC01 dose and trial; VRC01 did not prevent acquisition of other HIV-1 isolates. CONCLUSIONS: VRC01 did not prevent overall HIV-1 acquisition more effectively than placebo, but analyses of VRC01-sensitive HIV-1 isolates provided proof-of-concept that bnAb prophylaxis can be effective. (Supported by the National Institute of Allergy and Infectious Diseases; HVTN 704/HPTN 085 and HVTN 703/HPTN 081 ClinicalTrials.gov numbers, NCT02716675 and NCT02568215.).


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Amplamente Neutralizantes/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , HIV-1 , Adolescente , Adulto , África Subsaariana/epidemiologia , América/epidemiologia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Amplamente Neutralizantes/efeitos adversos , Método Duplo-Cego , Europa (Continente)/epidemiologia , Feminino , Anticorpos Anti-HIV/efeitos adversos , Infecções por HIV/epidemiologia , HIV-1/efeitos dos fármacos , Humanos , Incidência , Masculino , Estudo de Prova de Conceito , Adulto Jovem
4.
BMC Public Health ; 24(1): 1876, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39004714

RESUMO

BACKGROUND: Multipurpose prevention technologies (MPTs) are products capable of simultaneously addressing multiple sexual and reproductive health needs such as unwanted pregnancy, STIs including HIV-1, and other reproductive tract infections. MPTs are urgently needed to address the double burden of unplanned pregnancy and HIV. While condoms are currently the only accessible MPTs, they are not solely under a woman's control, and female condoms face limitations due to poor acceptability and high cost. METHODS: We conducted a sub-analysis of qualitative data from 39 couples participating in the MTN 045 study to examine the perception of couples on choice and acceptability of a "2 in 1" MPT that combines HIV and pregnancy prevention. RESULTS: Couples recognized the benefits of MPTs for HIV and pregnancy prevention but perceptions tied to each indication and a novel prevention technology tool raised important concerns relevant to use of future MPTs. In the study, participants' perceptions of MPT use were influenced by pregnancy planning. When the timing was less critical, they prioritized HIV prevention. Misinformation about family planning methods, including MPTs, affected decision-making with potential to hinder uptake of future MPTs. Concerns about side effects, such as weight gain and hormonal imbalances, influenced willingness to use MPTs. CONCLUSION: Addressing the myths and misconceptions surrounding the use of contraceptives is crucial in promoting their acceptance and ultimate use. Strategies for addressing the drawbacks women might experience while using a particular product should be in place as new MPTs progress through the development pipeline and approach roll-out.


Assuntos
Infecções por HIV , Humanos , Feminino , Masculino , Adulto , Infecções por HIV/prevenção & controle , Gravidez , Pesquisa Qualitativa , Comportamento de Escolha , Anticoncepção/métodos , Anticoncepção/psicologia , Adulto Jovem , Conhecimentos, Atitudes e Prática em Saúde , Serviços de Planejamento Familiar
5.
AIDS Behav ; 27(1): 198-207, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35776249

RESUMO

We conducted a secondary analysis of discrete choice experiment (DCE) data from 395 couples enrolled in the Microbicide Trials Network (MTN)-045/CUPID study in Uganda and Zimbabwe to understand couple decision making around choice of multipurpose prevention technologies (MPTs) to prevent both HIV and pregnancy. Members of couples completed the same DCE, first separately then jointly, choosing between two hypothetical MPTs in a series of nine questions. Most couples either had similar preferences at the outset or had equal decision-making around MPTs (62%). Couples with male influence (17%) were more likely to use contraceptive pills with a male partner's knowledge and couples with female influence (21%) were less likely to have shared decision making about family planning. Males influenced discussion around MPT duration, side effects, menstrual changes, and how the vagina feels during sex. Decision making was relatively shared, though decisions around certain attributes were more likely to be dominated by male partners.


Assuntos
Infecções por HIV , Gravidez , Humanos , Masculino , Feminino , Infecções por HIV/prevenção & controle , Serviços de Planejamento Familiar , Tomada de Decisões , Uganda , Zimbábue
6.
AIDS Behav ; 27(3): 1030-1043, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36066762

RESUMO

MTN-025/HOPE was an open-label trial of the dapivirine vaginal ring conducted in four African countries between 2016 and 2018. Women were first offered one ring monthly (at baseline, months 1 and 2), thereafter, transitioned to a more applicable real-world dispensation schedule, - 3 rings quarterly (at months 3, 6 and 9). Logistic regression analysis was used to assess correlates of ring acceptance at baseline and through follow-up. A total of 1456 women (median age 31 years) enrolled, 1342 (92.2%) accepted the ring at baseline and 1163 (79.9%) accepted the ring(s) at all visits. Changing ring dispensation from a monthly to a quarterly schedule had no negative effect on acceptance. Having a primary partner and him knowing about the ring being offered in HOPE, use of long-acting contraception (implants, injections, IUDs) or sterilization were associated with ring acceptance, along with prior strong intention to use the ring in the future. Efforts should consider these factors when rolling out the ring for HIV prevention.


Assuntos
Fármacos Anti-HIV , Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Adulto , Feminino , Humanos , Masculino , África , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Pirimidinas/uso terapêutico
7.
AIDS Behav ; 26(12): 3848-3861, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35674885

RESUMO

End-user input early in biomedical product development may optimize design to support high uptake and adherence. We interviewed 400 couples (800 total participants) in Uganda and Zimbabwe to assess their preferences for multipurpose prevention technologies (MPTs) for HIV and pregnancy prevention. Using a discrete choice experiment, couples made a series of choices between hypothetical MPTs, including oral tablets and vaginal rings, inserts, and films and completed an interviewer-administered questionnaire assessing sociodemographic and behavioral measures. Most couples preferred presented MPTs over male condoms. Couples' MPT choices in both countries were influenced most by the combination of product form and dosing frequency, with monthly dosing preferred over daily. Analysis highlighted differences by country as to which side effects were most important: Ugandan couples placed greater importance on effects on the vaginal environment during sex, whereas Zimbabwean couples placed more importance on changes to menstruation and other side effects (headache, cramps). Couples' preferences signaled an openness to new product forms and more frequent dosing if preferred characteristics of other attributes were achieved.


Assuntos
Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Gravidez , Feminino , Masculino , Humanos , Zimbábue/epidemiologia , Uganda , Anticoncepção/métodos , Infecções por HIV/prevenção & controle
8.
Afr J AIDS Res ; 21(4): 354-363, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36538544

RESUMO

We examined men's influence on women's interest in biomedical HIV prevention during pregnancy and breastfeeding through structured questionnaires and focus group discussions with currently or recently pregnant and breastfeeding (P/BF) women (n = 65), men with P/BF partners (n = 63) and mothers/mothers-in-law of P/BF women (n = 68) in eastern and southern Africa. Data were transcribed, coded and summarised into analytical memos. Men were depicted by most participants as joint decision-makers and influencers of women's use of HIV prevention. Cultural and religious norms depicting men as heads, breadwinners and protectors of the family were cited to legitimise their involvement in decision-making. Male partner education and engagement were recommended to garner their support in women's HIV prevention. This study elucidates how P/BF women's ability to prevent HIV is shaped by traditional and contemporary gender norms in social settings and locations where the study was conducted. Findings may aid intervention design to engage men for P/BF women's effective use of microbicide and oral PrEP.


Assuntos
Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Gravidez , Humanos , Masculino , Feminino , Parceiros Sexuais , Aleitamento Materno , Infecções por HIV/prevenção & controle , Identidade de Gênero
9.
AIDS Behav ; 25(1): 124-138, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32588257

RESUMO

The attributes of an HIV microbicide may affect its acceptability, uptake and use. Quatro, a clinical study with a qualitative component, was conducted to elicit input from end-users and key informants (KIs) on four different placebo vaginal microbicide delivery forms; fast dissolving insert, ring, film and gel. In-depth interviews and focus group discussions were conducted with young women, their male partners and KIs, to explore acceptability and preferences of the four placebo products, with the intention of improving product attributes, adherence, and consequently, long term effectiveness. None of the four microbicide delivery forms stood well above others as the most preferred. Product attributes; long-action, ease of use, invisibility, female initiated and non-interference during sex were favourable in both countries. Despite preference for the long-action, on-demand products were the most liked by women. Qualitative data from the Quatro study provided rich feedback on specific attributes important to the acceptability of four HIV prevention product platforms currently in development, enabling more informed and guided product development efforts moving forward.


Assuntos
Antivirais , Infecções por HIV , Administração Intravaginal , Antivirais/administração & dosagem , Transmissão de Doença Infecciosa/prevenção & controle , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Parceiros Sexuais , África do Sul , Zimbábue
10.
AIDS Behav ; 25(2): 447-458, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32833192

RESUMO

Fostering adherence and open communication about adherence challenges is key to harnessing the potential of biomedical HIV prevention products. We describe the counseling intervention and objective adherence measure feedback process implemented to support adherence to the dapivirine vaginal ring among participants in four sub-Saharan countries and present findings on the counselors' likeability and acceptability of the intervention. Most counselors (N = 42; 86%) liked Options counseling "very much" and during in-depth interviews (N = 22), reported that the intervention reshaped their adherence counselling approach by emphasizing understanding participants' experiences using the ring, which facilitated open discussion of adherence challenges. Counselors found that reframing residual drug level (RDL) discussions from the "adherence" to "protection" perspective encouraged adherence among consistent users and facilitated decisions to switch to a different HIV prevention approach among infrequent users. Among counselors, 24% said participants "liked it very much" while 26% said that participants "liked it a little" possibly due to two main complaints: perceived repetitiousness of sessions and variability in the RDL assay, which at times resulted in unexpected low RDLs.


RESUMEN: Fomentar la adherencia y la comunicación abierta sobre los desafíos con la adherencia es clave para aprovechar el potencial de los productos biomédicos de prevención del VIH. Describimos la intervención de consejería y el proceso de compartir los resultados de medidas objetivas de adherencia con participantes en cuatro países subsaharianos para apoyar la adherencia al anillo vaginal de dapivirine y presentamos los resultados sobre la agradabilidad y la aceptabilidad de la intervención a los consejeros. A la mayoría de los consejeros (N=42; 86%) "les gustó mucho" la consejería quienes, durante entrevistas en profundidad (N=22) y reportaron que la intervención cambió su aproximación a la consejería sobre la adherencia. Se enfocaban más en comprender la experiencia de uso del anillo entre las participantes, lo cual facilitaba una conversación abierta sobre posibles desafíos a la adherencia. Los consejeros encontraron que cambiar el enfoque de "adherencia" a "protección" en las conversaciones sobre los niveles residuos de drogas fomentaba la adherencia entre las mujeres que usaban el anillo consistentemente y facilitaba la decisión de cambiar a otro método de prevención del VIH entre las mujeres que lo usaban con poca frecuencia. Entre los consejeros, 24% dijeron que a las participantes "les gustó mucho" la consejería y 26% que a las participantes "les gustó un poco". Es posible que esto se deba a dos quejas principales: la percepción de que las sesiones sean repetitivas y la variabilidad en el ensayo de los niveles residuos de drogas, lo cual a veces resultaba en niveles bajos inesperados.


Assuntos
Infecções por HIV , Pirimidinas/uso terapêutico , Aconselhamento , Retroalimentação , Feminino , Infecções por HIV/prevenção & controle , Humanos
11.
PLoS Comput Biol ; 15(4): e1006952, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30933973

RESUMO

The broadly neutralizing antibody (bnAb) VRC01 is being evaluated for its efficacy to prevent HIV-1 infection in the Antibody Mediated Prevention (AMP) trials. A secondary objective of AMP utilizes sieve analysis to investigate how VRC01 prevention efficacy (PE) varies with HIV-1 envelope (Env) amino acid (AA) sequence features. An exhaustive analysis that tests how PE depends on every AA feature with sufficient variation would have low statistical power. To design an adequately powered primary sieve analysis for AMP, we modeled VRC01 neutralization as a function of Env AA sequence features of 611 HIV-1 gp160 pseudoviruses from the CATNAP database, with objectives: (1) to develop models that best predict the neutralization readouts; and (2) to rank AA features by their predictive importance with classification and regression methods. The dataset was split in half, and machine learning algorithms were applied to each half, each analyzed separately using cross-validation and hold-out validation. We selected Super Learner, a nonparametric ensemble-based cross-validated learning method, for advancement to the primary sieve analysis. This method predicted the dichotomous resistance outcome of whether the IC50 neutralization titer of VRC01 for a given Env pseudovirus is right-censored (indicating resistance) with an average validated AUC of 0.868 across the two hold-out datasets. Quantitative log IC50 was predicted with an average validated R2 of 0.355. Features predicting neutralization sensitivity or resistance included 26 surface-accessible residues in the VRC01 and CD4 binding footprints, the length of gp120, the length of Env, the number of cysteines in gp120, the number of cysteines in Env, and 4 potential N-linked glycosylation sites; the top features will be advanced to the primary sieve analysis. This modeling framework may also inform the study of VRC01 in the treatment of HIV-infected persons.


Assuntos
Anticorpos Monoclonais/farmacologia , Proteína gp160 do Envelope de HIV/genética , Proteína gp160 do Envelope de HIV/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Anticorpos Amplamente Neutralizantes , Antígenos CD4 , Simulação por Computador , Previsões/métodos , Glicosilação , Anticorpos Anti-HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Ligação Proteica
12.
AIDS Care ; 32(9): 1082-1091, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31899954

RESUMO

Pre-Exposure Prophylaxis (PrEP) trials often implement counseling to support product adherence. Counseling fidelity can vary significantly across providers and time. Fidelity monitoring can ensure that counseling is delivered as designed. We describe the process, feasibility, and outcomes of monitoring Options counseling fidelity in an open-label study of the dapivirine vaginal ring MTN-025/HOPE. After initial training, 63 counselors from 14 sites in Sub-Sahara Africa audio-recorded counseling sessions with study participants. Sessions were rated by a New York-based team that included bilingual emigres from the study countries. Completed session rating forms were sent to counselors to provide feedback and counseling difficulties were discussed during monthly calls. Of 1456 study participants, 85.7% consented to at least one session, and 20% to all sessions, being audio-recorded. Among 9926 study visits in which Options was expected to occur, 5366 (54.1%) Options sessions were audio-recorded, of which 1238 (23.1%) were reviewed; 1039 (83.9%) were rated as "good" or "fair." Eleven counselors who failed to consistently deliver the intervention were reassigned to back-up status. This study demonstrates the feasibility and benefits of monitoring counseling fidelity using audio-recordings in a multi-site, multi-language, multi-country PrEP trial. Given the investment necessary to conduct such trials, providing counseling oversight is highly warranted.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , África Subsaariana , Aconselhamento , Feminino , Infecções por HIV/prevenção & controle , Humanos , New York
13.
N Engl J Med ; 375(22): 2121-2132, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-26900902

RESUMO

BACKGROUND: Antiretroviral medications that are used as prophylaxis can prevent acquisition of human immunodeficiency virus type 1 (HIV-1) infection. However, in clinical trials among African women, the incidence of HIV-1 infection was not reduced, probably because of low adherence. Longer-acting methods of drug delivery, such as vaginal rings, may simplify use of antiretroviral medications and provide HIV-1 protection. METHODS: We conducted a phase 3, randomized, double-blind, placebo-controlled trial of a monthly vaginal ring containing dapivirine, a non-nucleoside HIV-1 reverse-transcriptase inhibitor, involving women between the ages of 18 and 45 years in Malawi, South Africa, Uganda, and Zimbabwe. RESULTS: Among the 2629 women who were enrolled, 168 HIV-1 infections occurred: 71 in the dapivirine group and 97 in the placebo group (incidence, 3.3 and 4.5 per 100 person-years, respectively). The incidence of HIV-1 infection in the dapivirine group was lower by 27% (95% confidence interval [CI], 1 to 46; P=0.046) than that in the placebo group. In an analysis that excluded data from two sites that had reduced rates of retention and adherence, the incidence of HIV-1 infection in the dapivirine group was lower by 37% (95% CI, 12 to 56; P=0.007) than that in the placebo group. In a post hoc analysis, higher rates of HIV-1 protection were observed among women over the age of 21 years (56%; 95% CI, 31 to 71; P<0.001) but not among those 21 years of age or younger (-27%; 95% CI, -133 to 31; P=0.45), a difference that was correlated with reduced adherence. The rates of adverse medical events and antiretroviral resistance among women who acquired HIV-1 infection were similar in the two groups. CONCLUSIONS: A monthly vaginal ring containing dapivirine reduced the risk of HIV-1 infection among African women, with increased efficacy in subgroups with evidence of increased adherence. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT01617096 .).


Assuntos
Infecções por HIV/prevenção & controle , HIV-1 , Pirimidinas/administração & dosagem , Inibidores da Transcriptase Reversa/administração & dosagem , Adolescente , Adulto , África Austral/epidemiologia , Fatores Etários , Método Duplo-Cego , Farmacorresistência Viral , Feminino , Infecções por HIV/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade , Cooperação do Paciente , Pirimidinas/efeitos adversos , Inibidores da Transcriptase Reversa/efeitos adversos , Vagina , Adulto Jovem
14.
Cult Health Sex ; 21(11): 1209-1224, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30657023

RESUMO

Rumours may influence health-related behaviours, including the uptake of and adherence to HIV prevention products. This study assessed the safety and effectiveness of a vaginal ring delivering the antiretroviral dapivirine for HIV prevention in Africa. We explored negative rumours about study participation and the vaginal ring amongst study participants and their communities in Malawi, Uganda, South Africa and Zimbabwe. In total 214 women participated in either single or serial in-depth interviews, or a focus group discussion. Three key findings emerged in the data. Firstly, rumours reflected fears concerning the ring and trial participation. Given the historical-political context of the countries in which the trial was conducted, the ring's investigational nature and its foreign origin, ring use was rumoured to cause negative health outcomes such as cancer and infertility and to be associated with practices such as witchcraft or Satanism. The salience of these rumours varied by country. Secondly, rumours reportedly affected participants' adherence to the ring, and other women's willingness to participate in the study. Finally, participants reported that participant engagement activities helped address rumours, resulting in enhanced trust and rapport between staff and participants.


Assuntos
Antirretrovirais/uso terapêutico , Dispositivos Anticoncepcionais Femininos , Enganação , Infecções por HIV , Aceitação pelo Paciente de Cuidados de Saúde , Pirimidinas/uso terapêutico , Adulto , Feminino , Grupos Focais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , HIV-1/isolamento & purificação , Humanos , Entrevistas como Assunto , Malaui , África do Sul , Zimbábue
15.
AIDS Behav ; 22(3): 877-886, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28110473

RESUMO

Accurate estimates of study product use are critical to understanding and addressing adherence challenges in HIV prevention trials. The VOICE trial exposed a significant gap between self-reported adherence and drug detection. The VOICE-D qualitative study was designed to better understand non-adherence during VOICE, and was conducted in 2 stages: before (stage 1) and after (stage 2) drug detection results were provided to participants. Transcripts from 44 women who participated in both stages were analysed to understand the effect of presenting drug detection data on narratives of product use. Thirty-six women reported high adherence in stage 1, yet admitted non-use in stage 2, three reported high adherence in both stages (contrary to their drug detection results) and five had consistent responses across both stages and drug results. Presenting objective measures of use may facilitate more accurate product use reporting and should be evaluated in future prevention trials.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Adesão à Medicação , Profilaxia Pré-Exposição , Adulto , Feminino , Infecções por HIV/epidemiologia , Humanos , Pesquisa Qualitativa , Autorrelato , África do Sul/epidemiologia , Uganda/epidemiologia , Zimbábue/epidemiologia
16.
J Acquir Immune Defic Syndr ; 95(1): 35-41, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37732881

RESUMO

BACKGROUND: Clinical trials of dapivirine (DPV) vaginal ring have shown it is safe, effective, and desired by women as an HIV prevention option. The risk of drug resistance is a potential concern for DPV ring users who acquire HIV. We conducted a comprehensive resistance evaluation of plasma samples from the women who seroconverted during the Microbicide Trials Network-025/HIV Open-label Prevention Extension (HOPE) study of DPV ring. METHODS: Plasma collected on the visit at which seroconversion was detected was tested by next-generation sequencing with unique molecular identifiers for non-nucleoside reverse transcriptase inhibitor (NNRTI) drug resistance mutations (DRM) present at ≥1% frequency. Bulk-cloned plasma-derived recombinant HIV was phenotyped in a TZM-bl-based assay for susceptibility to DPV and other NNRTI. HIV-1 RNA was retrospectively quantified in plasma samples collected before HIV seroconversion. RESULTS: Among 38 participants who seroconverted in HOPE, 7 (18%) had NNRTI DRM detected by next-generation sequencing with unique molecular identifiers including A98G, K103N, V106M, E138A, and V179D. Six of 7 samples with NNRTI DRM had <3-fold reduction in susceptibility to DPV. Only 1 sample with K103N and V179I polymorphism had 9-fold reduction in susceptibility to DPV, but this genotype occurred in an individual who did not use DPV ring, likely indicating transmitted resistance. Detection of NNRTI resistance was not higher in individuals who remained on DPV ring >3 months after acquiring HIV infection. CONCLUSIONS: NNRTI resistance among women who seroconverted during HOPE was infrequent and selection of DPV-specific mutations was not detected. DPV ring is considered a safe and effective option for HIV prevention in women.


Assuntos
Fármacos Anti-HIV , Dispositivos Anticoncepcionais Femininos , Infecções por HIV , Soropositividade para HIV , Feminino , Humanos , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Estudos Retrospectivos , Inibidores da Transcriptase Reversa/uso terapêutico
17.
BMJ Open ; 14(3): e075381, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38479746

RESUMO

INTRODUCTION: Oral pre-exposure prophylaxis (PrEP) is a highly effective HIV prevention method; however, uptake and persistence have been low among southern African women. A dual prevention pill (DPP) that combines PrEP with oral contraception (OC) may increase PrEP use and better meet women's sexual and reproductive health needs. We will gauge the DPP's acceptability in two cross-over clinical trials. METHODS AND ANALYSIS: PC952 (Zimbabwe) and PC953 (South Africa) will compare acceptability, adherence and preference for an over-encapsulated DPP versus PrEP and OCs taken separately. HIV-negative, non-pregnant cisgender females in Johannesburg, South Africa (n=96, 16-40 years) and Harare, Zimbabwe (n=30, 16-24 years) will be randomised 1:1 to the order of regimens-DPP or two separate tablets-each used for three 28-day cycles, followed by a 6-month choice period in South Africa. Monthly clinic visits include HIV and pregnancy testing; safety assessments and risk reduction and adherence counselling. We will assess adherence (monthly) based on tenofovir diphosphate drug levels in dried blood spots and by self-report. We will evaluate acceptability (monthly) and preference (end of cross-over) via computer-assisted self-interviewing and in-depth interviews with a subset of participants. Data collection started in September 2022 and ended in January 2024. ETHICS AND DISSEMINATION: PC952 was approved by the Ministry of Health and Child Care, Medical Research Council, Research Council and Medicines Control Authority of Zimbabwe; the Chitungwiza City Health Ethics Committee; and the Joint Research Ethics Committee for the University of Zimbabwe Faculty of Medicine and Health Sciences and Parirenyatwa Group of Hospitals. PC953 was approved by the South African Health Products Regulatory Authority and the University of the Witwatersrand's Human Research Ethics Committee. The Population Council IRB approved both studies. We will disseminate results in open-access journals, clinical trials registries, and at local and international meetings and conferences. TRIAL REGISTRATION NUMBERS: NCT04778514, NCT04778527.


Assuntos
Anticoncepção , Infecções por HIV , Profilaxia Pré-Exposição , Feminino , Humanos , Fármacos Anti-HIV/uso terapêutico , Estudos Cross-Over , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Profilaxia Pré-Exposição/métodos , África do Sul/epidemiologia , Zimbábue , Ensaios Clínicos Controlados Aleatórios como Assunto , Adolescente , Adulto Jovem , Adulto
18.
J Int AIDS Soc ; 26 Suppl 2: e26115, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37439069

RESUMO

INTRODUCTION: The burden of HIV in sub-Saharan Africa (SSA) remains unacceptably high, and disproportionately affects girls and women. While the introduction of oral HIV pre-exposure prophylaxis (PrEP) in 2012 revolutionized HIV prevention, its effectiveness is dependent on user adherence and its implementation in SSA has faced numerous challenges. Patient-level, interpersonal and structural barriers, including, for example, daily pill burden, side effects, lack of partner support, testing and disclosure, and costs have been found to reduce adherence to oral PrEP. DISCUSSION: Long-acting extended delivery (LAED) formulations for PrEP, such as injectable long-acting cabotegravir (CAB-LA) and dapivirine vaginal ring (DPV-VR) are critical additions to the HIV prevention toolkit and are especially important for populations such as adolescent girls and young women (AGYW) and other key populations who remain at significant risk of HIV acquisition while facing substantial barriers to preventive services. These LAED formulations have been shown to result in better adherence and fewer side effects, with CAB-LA being superior to oral PrEP in reducing the risk of HIV acquisition. They can be used to overcome user burden and adherence challenges. However, the successful rollout of the DPV-VR and CAB-LA may be hampered by issues such as a shortage of healthcare providers (HCPs), inadequate parenteral medication infrastructure, increased workload for HCPs, patient concerns, the price of the medications and the possibility of drug resistance. CONCLUSIONS: SSA must develop laboratory capabilities for monitoring patients on LAED formulations and enhance research on developing more non-injectable LAED formulations. There is a need to train and retain more HCPs, implement task shifting, invest in healthcare infrastructure and integrate healthcare services. To reduce costs and improve availability, the region must advocate for patent license waivers for LAED formulations and procure drugs collectively as a region.


Assuntos
Infecções por HIV , Adolescente , Humanos , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Revelação , Instalações de Saúde , Pessoal de Saúde , África Subsaariana
19.
Front Reprod Health ; 5: 1279124, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034413

RESUMO

The global burden of HIV remains unacceptably high despite significant progress made in HIV treatment and prevention. There is an urgent need to scale up the comprehensive HIV prevention strategies that include pre-exposure prophylaxis (PrEP). Oral PrEP is highly effective in preventing HIV acquisition when taken regularly, but this remains a challenge for some at-risk individuals. Therefore, there is a need for other HIV prevention options. The dapivirine vaginal ring (DVR) and long-acting injectable cabotegravir (CAB-LA) are novel biomedical interventions that are safe and efficacious for HIV pre-exposure prophylaxis, as demonstrated in recently completed clinical trials. Timely roll-out and scalability of efficacious interventions depend on the registration process with the national medicine regulatory authorities (NMRAs). The Medicines Control Authority of Zimbabwe (MCAZ) was the first NMRA globally to approve the DVR in July 2021 and the first in Africa to approve CAB-LA for HIV prevention in July 2022. The regulatory review process for DVR and CAB-LA by MCAZ took 4.5 and 5.5 months, respectively. This efficient review process of the two interventions by MCAZ, a regulatory body in a resource-limited setting, provides important lessons to shorten timelines between the completion of the clinical development process and the registration of essential medicines.

20.
Nat Med ; 29(11): 2748-2752, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37798438

RESUMO

Pre-exposure prophylaxis (PrEP) with tenofovir (TFV) disoproxil fumarate and emtricitabine administered orally daily is effective in preventing human immunodeficiency virus (HIV) acquisition in both men and women with sufficient adherence; however, the adherence-efficacy relationship in cisgender women has not been well established. We calculated the adherence-efficacy curve for cisgender women by using HIV incidence and plasma TFV concentration data from three trials (FEM-PrEP, VOICE and Partners PrEP). We imputed TFV diphosphate (TFV-DP) concentrations, a measure of long-term adherence, from TFV quantification by using data from the HIV Prevention Trials Network 082 study, which measured both TFV-DP and TFV concentrations. Two, four and seven pills per week reduced HIV incidence by 59.3% (95% credible interval (CrI) 29.9-95.8%), 83.8% (95% CI 51.7-99.8%) and 95.9% (95% CI 72.6-100%), respectively. Our adherence-efficacy curve can be validated and updated by HIV prevention studies that directly measure TFV-DP concentrations. The curve suggests that high adherence confers high protection in cisgender women. However, the lower efficacy with partial adherence highlights the need for new PrEP products and interventions to increase adherence.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Masculino , Humanos , Feminino , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , HIV , Emtricitabina/uso terapêutico , Tenofovir/uso terapêutico , Adesão à Medicação
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