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1.
J Infect Dis ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39047063

RESUMO

BACKGROUND: We previously reported the effect of contraception on cervical tenofovir concentrations in Ugandan women living with HIV. Here we explored the role of cervicovaginal cytokines and drug metabolizing enzymes and transporters (DMETs) to elucidate FGT drug disposition in a Ugandan cohort. METHODS: Cervicovaginal fluid and cervical biopsies were collected from Ugandan women living with HIV receiving tenofovir/lamivudine-based therapy and intramuscular depot medroxyprogesterone acetate (DMPA-IM; n=25), copper IUD (cuIUD; n=12), or condoms (n=13) as contraception. Cytokines were measured in cervicovaginal fluid (CVF). Ectocervical tenofovir diphosphate (TFVdp) and lamivudine triphosphate (3TCtp), dATP/dCTP concentrations, and immune marker/DMETs gene expression were measured in cervical biopsies. RESULTS: Cervical 3TCtp was not correlated with any CVF cytokines. Cervical TFVdp was correlated with IL-10, IL-7, and IL-17 in CVF. CCR5 mRNA expression in cervical biopsies was higher in cuIUD-users versus condoms-users. Using multivariable linear regression, CVF IL-17, tissue dATP, plasma estradiol, and plasma tenofovir were all significant predictors of cervical TFVdp. Tissue dCTP and plasma lamivudine were significant predictors of cervical 3TCtp. CONCLUSIONS: TFVdp concentrations in cervix appear to be influenced by local inflammation. In contrast, 3TCtp FGT exposure was not affected by genital inflammation or DMETS. CuIUD users have more immune cells present, which may in turn influence local TFVdp disposition.

2.
Clin Infect Dis ; 70(8): 1717-1724, 2020 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-31131846

RESUMO

BACKGROUND: Effective concentrations of antiretrovirals in the female genital tract (FGT) are critical for suppression of viral shedding or effective preexposure prophylaxis. The disposition of tenofovir diphosphate (TFV-DP) and emtricitabine triphosphate (FTC-TP) in the FGT have been previously described. Despite widespread use, however, lamivudine triphosphate (3TC-TP) exposure in the FGT is unknown. Depot medroxyprogesterone acetate (DMPA) and vaginal dysbiosis have been implicated in increased risk of human immunodeficiency virus (HIV) acquisition, but whether they alter TFV-DP or 3TC-TP exposure, and therefore compromise prevention efficacy, is unknown. METHODS: Fifty premenopausal women living with HIV in Kampala, Uganda, and receiving daily tenofovir disoproxil fumarate/lamivudine were recruited. Ectocervical biopsies were obtained for quantification of TFV-DP and 3TC-TP using liquid chromatography-mass spectrometry. 16S ribosomal RNA gene sequencing was performed on DNA extracted from vaginal swabs. Wilcoxon rank-sum was used to test for differences between contraceptive groups. RESULTS: 3TC-TP concentrations were on average 17-fold greater than TFV-DP concentrations in cervical tissues. TFV-DP concentrations in cervical biopsies were 76% greater in DMPA users compared with women using nonhormonal contraception (n = 23 per group). Abundance of Lactobacillus in vaginal swabs was correlated with 3TC-TP concentrations in cervical tissues. CONCLUSIONS: We found that TFV-DP concentrations were significantly greater in DMPA users compared with women using nonhormonal contraception, suggesting that prevention efficacy is unlikely to be compromised by DMPA use. Similar to reports of FTC-TP, 3TC-TP exposure was significantly greater than TFV-DP in cervical tissue and was correlated with abundance of Lactobacillus. These data support lamivudine as an option for preexposure prophylaxis. CLINICAL TRIALS REGISTRATION: NCT03377608.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Microbiota , Profilaxia Pré-Exposição , Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Citidina Trifosfato/análogos & derivados , Didesoxinucleotídeos , Emtricitabina/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Lamivudina/análogos & derivados , Lamivudina/uso terapêutico , Acetato de Medroxiprogesterona/uso terapêutico , Organofosfatos , Tenofovir/uso terapêutico , Uganda
3.
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
4.
AIDS ; 33(14): 2237-2244, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31408030

RESUMO

OBJECTIVES: Assessment of safety is an integral part of real-time monitoring in clinical trials. In HIV prevention research, safety of investigational products and trial participation has been expanded to include monitoring for 'social harms', generally defined as negative consequences of trial participation that may manifest in social, psychological, or physical ways. Further research on social harms within HIV prevention research is needed to understand the potential safety risks for women and advance the implementation of prevention methods in real-world contexts. METHODS: Secondary analysis of quantitative data from three randomized, double-blind, placebo-controlled trials of microbicide candidates in sub-Saharan Africa was conducted. Additionally, we assessed data from two prospective cohort studies that included participants who became HIV-positive or pregnant during parent trials. RESULTS: Social harms reporting was low across the largest and most recent microbicide studies. Social harm incidence per 100 person-years ranged from 1.10 (95% CI 0.78-1.52) to 3.25 (95% CI 2.83-3.74) in the phased trials. Reporting differed by dosing mechanism (e.g. vaginal gel, oral tablet, ring) and study, most likely as a function of measurement differences. Social harms were most frequently associated with male partners, rather than, for example, experiences of stigma in the community. CONCLUSION: Measurement and screening for social harms is an important component of conducting ethical research of novel HIV prevention methods. To date, social harm incidence reported in microbicide trials has been relatively low (<4% per 100 person-years), and the majority have been partner-related events. However, any incidence of social harm within the context of HIV prevention is important to capture and understand for the safety of individuals, and for the successful impact of prevention methods in a real-world context.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Violência por Parceiro Íntimo , Participação do Paciente , África Subsaariana , Fármacos Anti-HIV/efeitos adversos , Método Duplo-Cego , Ética em Pesquisa , Feminino , Humanos , Masculino , Estudos Prospectivos , Segurança , Cremes, Espumas e Géis Vaginais/efeitos adversos , Cremes, Espumas e Géis Vaginais/uso terapêutico
5.
HIV Clin Trials ; 19(5): 165-171, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30370830

RESUMO

BACKGROUND: The success of longitudinal trials depends greatly on using effective strategies to retain participants and ensure internal validity, maintain sufficient statistical power, and provide for the generalizability of study results. OBJECTIVE: This paper describes the challenges and specific strategies used to retain participants in a Phase 2B safety and effectiveness study of daily oral and vaginal tenofovir formulations for the prevention of HIV-1 infection in the MTN-003 (VOICE) trial in Kampala, Uganda. METHODS: Once enrolled, participants were seen every 28 days at the research site and their study product was re-filled. Challenges to retention included a mobile population, non-disclosure of study participation to spouse/family, and economic constraints. Strategies used to maintain high participation rates included the use of detailed locator information, a participant tracking database, regular HIV/STI testing, and the formation of close bonds between staff and subjects. RESULTS: We enrolled 322 women out of the 637 screened. The overall retention rate was 95% over a 3 year follow up period. Only 179 (3%) out of the 6124 expected visits were missed throughout study implementation. Reasons for missed visits included: participants thinking that they did not need frequent visits due to their HIV negative status, time constraints due to commercial sex work, and migration for better employment. CONCLUSIONS: With the implementation of multi-faceted comprehensive follow-up and retention strategies, we achieved very high retention rates in the MTN-003 study. This paper provides a blueprint for effective participant retention strategies for other longitudinal HIV prevention studies in resource-limited settings in Sub-Saharan Africa.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Combinação Emtricitabina e Fumarato de Tenofovir Desoproxila/administração & dosagem , Infecções por HIV/prevenção & controle , Participação do Paciente , Tenofovir/administração & dosagem , Administração Intravaginal , Administração Oral , Adulto , Combinação Albuterol e Ipratrópio/administração & dosagem , Ensaios Clínicos como Assunto/métodos , Ensaios Clínicos como Assunto/normas , Ensaios Clínicos como Assunto/estatística & dados numéricos , Feminino , Géis , Humanos , Estudos Longitudinais , Uganda
6.
HIV Clin Trials ; 19(1): 8-14, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29268654

RESUMO

BACKGROUND: Safety data on pregnancy and fetal outcomes among women in HIV prevention trials are urgently needed to inform use of effective antiretroviral agents for HIV prevention. We describe an effective, efficient, and novel method to prospectively collect perinatal safety data concurrent with on-going parent clinical trials. METHODS: The Microbicide Trials Network (MTN)-016 study is a multinational prospective pregnancy exposure registry designed to capture pregnancy and neonatal outcomes. Studies currently contributing data to this registry included phase I and II safety trials with planned exposures to candidate HIV prevention agents, as well as phase IIB and III efficacy trials capturing data on pregnancy and infant outcomes following inadvertent fetal exposure during study participation. RESULTS: To date, participants from two phase I studies and two effectiveness trials have participated in MTN-016, resulting in 420 pregnant women and 381 infants enrolled. Infant retention has been high, with 329 of 381 (86%) infants completing the 12-month follow-up visit. CONCLUSION: In a research setting context, it is feasible to establish and implement a prospective, multinational HIV chemoprophylaxis pregnancy registry that will generate pregnancy exposure data in a robust fashion.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/farmacologia , Infecções por HIV/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Sistema de Registros , Fármacos Anti-HIV/efeitos adversos , Estudos de Coortes , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Internacionalidade , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico
7.
J Acquir Immune Defic Syndr ; 79(5): 566-572, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30383589

RESUMO

BACKGROUND: Monthly use of the dapivirine vaginal ring has been shown to be safe and effective for HIV-1 prevention in nonpregnant reproductive-aged women. The impact of dapivirine on pregnancy outcomes and infant is not known. We compared pregnancy incidence and outcomes by study arm among HIV-1-uninfected women who became pregnant while participating in MTN-020/ASPIRE. METHODS: ASPIRE was a randomized, double-blind, placebo-controlled phase III safety and effectiveness study of the dapivirine ring for HIV-1 prevention. Sexually active women aged 18-45 years from Malawi, South Africa, Uganda, and Zimbabwe were enrolled. Urine pregnancy tests were performed monthly, and, if positive, study product was withheld during pregnancy and breastfeeding. Pregnancy-related outcomes included the following: pregnancy incidence, pregnancy outcomes (live birth, preterm birth, pregnancy loss, and congenital anomalies), and infant growth. RESULTS: Of 2629 women enrolled in ASPIRE, 169 became pregnant during follow-up, resulting in 179 incident pregnancies and 181 pregnancy outcomes. No difference in pregnancy incidence by study arm was observed (hazard ratio = 0.93; 95% confidence interval: 0.68 to 1.26). The distribution of pregnancy outcomes was similar by study arm, and no difference was noted in the frequency or pattern of congenital anomalies or infant growth parameters by study arm. CONCLUSIONS: Dapivirine use in the periconception period does not seem to be associated with adverse effects on pregnancy or infant outcomes. Our findings provide support for additional safety studies of the dapivirine ring throughout pregnancy.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Dispositivos Anticoncepcionais Femininos , Infecções por HIV/prevenção & controle , Resultado da Gravidez , Pirimidinas/administração & dosagem , Adolescente , Adulto , África Subsaariana , Desenvolvimento Infantil , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Placebos/administração & dosagem , Gravidez , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-29403577

RESUMO

This paper will discuss the integration of electronic Case Report Forms (e-CRFs) into an already existing Android-based Audio Computer-Assisted Self-Interview (ACASI) software solution that was developed for a public health project in Kampala, Uganda, the technical outcome results, and lessons learned that may be useful to other projects requiring or considering such a technology solution. The developed product can function without a connection to the Internet and allows for synchronizing collected data once connectivity is possible. Previously, only paper-based CRFs were utilized at the Uganda project site. A subset or select group of CRFs were targeted for integration with ACASI in order to test feasibility and success. Survey volume, error rate, and acceptance of the system, as well as the operational and technical design of the solution, will be discussed.

9.
PLoS One ; 12(6): e0178594, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28658251

RESUMO

BACKGROUND: Little is known regarding HIV disease outcomes among individuals who become infected with HIV while receiving antiretroviral medications for prevention. We compared HIV disease parameters among women who seroconverted while receiving tenofovir-containing oral or vaginal pre-exposure prophylaxis (PrEP) to placebo. METHODS: Participants with HIV seroconversion in a randomized placebo-controlled trial of oral tenofovir, oral tenofovir/emtricitabine, and vaginal tenofovir gel (MTN-003) were followed in a longitudinal cohort study (MTN-015). The effect of oral and vaginal tenofovir-containing PrEP on HIV disease progression was compared to placebo using linear mixed effects and Cox proportional hazard models, as appropriate. Additional analyses were performed to compare the outcomes among participants with detectable tenofovir or emtricitabine in plasma at the first quarterly visit in MTN-003. RESULTS: A total of 224 participants were included in the analysis; 93% from South Africa and 94% clade C virus. No differences in HIV RNA at steady state or the trajectory over 12 months were observed for each active arm compared to placebo; tenofovir gel recipients had higher CD4+ T cell counts (722 vs 596 cells/mm3; p = 0.02) at 90 days after estimated HIV seroconversion and higher average rates of change over 12 months compared to placebo (-181 vs -92 cells/mm3 per year; p = 0.08). With a median follow-up of 31 months, no significant differences were observed for time to CD4+ T cell count ≤350 cells/mm3, or the composite endpoint of CD4+ T cells ≤350 cells/mm3, initiation of antiretroviral therapy or death for each active arm compared to placebo. Additionally, there were no significant differences in the HIV RNA or CD4+ T cell counts at baseline, the change to month 12, or any disease progression outcomes among participants with oral drug detected and no oral drug detected compared to placebo. CONCLUSIONS: No clinically significant differences in HIV seroconversion outcomes were observed among women randomized to tenofovir-containing oral or vaginal PrEP regimens, however low overall adherence limits the generalizability of these findings.


Assuntos
Infecções por HIV/patologia , Inibidores da Transcriptase Reversa/uso terapêutico , Tenofovir/uso terapêutico , Adulto , Contagem de Linfócito CD4 , Progressão da Doença , Feminino , Infecções por HIV/prevenção & controle , Soropositividade para HIV , Humanos , Placebos , Carga Viral , Adulto Jovem
10.
J Acquir Immune Defic Syndr ; 76(2): e47-e51, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28542081

RESUMO

OBJECTIVE: To evaluate the potential for a clinically relevant drug-drug interaction with concomitant use of a dapivirine vaginal ring, a novel antiretroviral-based HIV-1 prevention strategy, and hormonal contraception by examining contraceptive efficacies with and without dapivirine ring use. DESIGN: A secondary analysis of women participating in MTN-020/ASPIRE, a randomized, double-blind, placebo-controlled trial of the dapivirine vaginal ring for HIV-1 prevention. METHODS: Use of a highly effective method of contraception was an eligibility criterion for study participation. Urine pregnancy tests were performed monthly. Pregnancy incidence by arm was calculated separately for each hormonal contraceptive method and compared using an Andersen-Gill proportional hazards model stratified by site and censored at HIV-1 infection. RESULTS: Of 2629 women enrolled, 2310 women returned for follow-up and reported using a hormonal contraceptive method at any point during study participation (1139 in the dapivirine arm and 1171 in the placebo arm). Pregnancy incidence in the dapivirine arm versus placebo among women using injectable depot medroxyprogesterone acetate was 0.43% vs. 0.54%, among women using injectable norethisterone enanthate was 1.15% vs. 0%, among women using hormonal implants was 0.22% vs. 0.69%, and among women using oral contraceptive pills was 32.26% vs. 28.01%. Pregnancy incidence did not differ by study arm for any of the hormonal contraceptive methods. CONCLUSIONS: Use of the dapivirine ring does not reduce the effectiveness of hormonal contraceptives for pregnancy prevention. Oral contraceptive pill use was associated with high pregnancy incidence, potentially because of poor pill adherence. Injectable and implantable methods were highly effective in preventing pregnancy.


Assuntos
Antirretrovirais/administração & dosagem , Anticoncepção , Anticoncepcionais Femininos/administração & dosagem , Dispositivos Anticoncepcionais Femininos , Pirimidinas/administração & dosagem , Adolescente , Adulto , Antirretrovirais/farmacologia , Anticoncepcionais Femininos/farmacologia , Anticoncepcionais Orais Hormonais/administração & dosagem , Anticoncepcionais Orais Hormonais/farmacologia , Método Duplo-Cego , Interações Medicamentosas , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Incidência , Acetato de Medroxiprogesterona/administração & dosagem , Acetato de Medroxiprogesterona/farmacologia , Pessoa de Meia-Idade , Noretindrona/administração & dosagem , Noretindrona/análogos & derivados , Noretindrona/farmacologia , Gravidez , Pirimidinas/farmacologia , Adulto Jovem
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