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1.
AIDS Behav ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158801

RESUMEN

Product adherence is critical to obtaining objective estimates of efficacy of pre-exposure prophylactic interventions against HIV-1 infection. With imperfect adherence, intention-to-treat analyses assess the collective effects of complete, sub-optimal and non-adherence, providing a biased and attenuated estimate of the average causal effect of an intervention. Using data from the MTN-020/ASPIRE phase III trial evaluating HIV-1 efficacy of the dapivirine vaginal ring, we conducted per-protocol, and adherence-adjusted causal inference analyses using principal stratification and marginal structural models. We constructed two adherence cut offs of ≥ 0.9 mg (low cutoff) and > 4.0 mg (high cutoff) that represent drug released from the ring over a 28-day period. The HIV-1 efficacy estimate (95% CI) was 30.8% (3.6%, 50.3%) (P = 0.03) from the per-protocol analysis, and 53.6% (16.5%, 74.3%) (P = 0.01) among the highest predicted adherers from principal stratification analyses using the low cutoff. Marginal structural models produced efficacy estimates (95% CIs) ranging from 48.8 (21.8, 66.4) (P = 0.0019) to 56.5% (32.8%, 71.9%) (P = 0.0002). Application of adherence-adjusted causal inference methods are useful in interpreting HIV-1 efficacy in secondary analyses of PrEP clinical trials.

2.
AIDS Care ; 36(1): 80-86, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37066990

RESUMEN

We assessed if acceptability of the dapivirine vaginal ring for HIV prevention differed among the subgroup of women who reported engaging in transactional sex prior to enrollment in MTN-020/ASPIRE (phase III trial in Malawi, South Africa, Uganda, and Zimbabwe, 2012-2015; n = 2629). Transactional sex was defined as receipt of money, goods, gifts, drugs, or shelter in exchange for sex in the past year. Dimensions of acceptability included: ease of use and physical sensation in situ, impacts on sex, partner's opinion, and likelihood of future use. We used Poisson regression models with robust standard errors to compare risk of acceptability challenges by baseline history of transactional sex. At product discontinuation, women exchanging sex found the ring comfortable (90%), easy to insert (92%) and nearly all (96%) were likely to use the ring in the future. Women who had exchanged sex were more likely to report feeling the ring during sex (ARR 1.43, 95% CI: 1.09, 1.89; p = 0.01) and slightly more likely to mind wearing the ring during menses (ARR 1.22, 95% CI: 1.01, 1,46; p = 0.04) and during sex (ARR 1.22, 95% CI: 1.02, 1.45; p = 0.03). Messaging and counseling should include enhanced support for use during sex and menses to support optimal use.


Asunto(s)
Fármacos Anti-VIH , Dispositivos Anticonceptivos Femeninos , Infecciones por VIH , VIH-1 , Pirimidinas , Femenino , Humanos , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Ensayos Clínicos Fase III como Asunto
3.
BMC Public Health ; 23(1): 1163, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37322510

RESUMEN

BACKGROUND: Adolescent girls and young women (AGYW) account for 29% of new HIV infections in Uganda despite representing just 10% of the population. Peer support improves AGYW linkage to HIV care and medication adherence. We evaluated the feasibility and acceptability of peer delivered HIV self-tests (HIVST) and oral pre-exposure prophylaxis (PrEP) to young women in Uganda. METHODS: Between March and September 2021, we conducted a pilot study of 30 randomly selected young women, aged 18-24 years, who had received oral PrEP for at least three months, but had suboptimal adherence as measured by urine tenofovir testing (< 1500 ng/ml). Participants were offered daily oral PrEP and attended clinic visits three and six months after enrollment. Between clinic visits, participants were visited monthly by trained peers who delivered HIVST and PrEP. Feasibility and acceptability of peer-delivered PrEP and HIVST (intervention) were measured by comparing actual versus planned intervention delivery and product use. We conducted two focus groups with young women, and five in-depth interviews with peers and health workers to explore their experiences with intervention delivery. Qualitative data were analyzed using thematic analysis. RESULTS: At baseline, all 30 enrolled young women (median age 20 years) accepted peer-delivered PrEP and HIVST. Peer delivery visit completion was 97% (29/30) and 93% (28/30) at three and six months, respectively. The proportion of participants with detectable tenofovir in urine was 93% (27/29) and 57% (16/28) at months three and six, respectively. Four broad themes emerged from the qualitative data: (1) Positive experiences of peer delivered HIVST and PrEP; (2) The motivating effect of peer support; (3) Perceptions of female controlled HIVST and PrEP; and (4) Multi-level barriers to HIVST and PrEP use. Overall, peer delivery motivated young women to use HIVST and PrEP and encouraged persistence on PrEP by providing non-judgmental client-friendly services and adherence support. CONCLUSION: Peer delivery of HIVST and oral PrEP was feasible and acceptable to this sample of young women with suboptimal PrEP adherence in Uganda. Future larger controlled studies should evaluate its effectiveness among African AGWY.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Adolescente , Humanos , Femenino , Adulto Joven , Adulto , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Autoevaluación , Uganda , Proyectos Piloto , Estudios de Factibilidad , Tenofovir/uso terapéutico , Fármacos Anti-VIH/uso terapéutico
4.
AIDS Behav ; 27(3): 1030-1043, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36066762

RESUMEN

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.


Asunto(s)
Fármacos Anti-VIH , Dispositivos Anticonceptivos Femeninos , Infecciones por VIH , Adulto , Femenino , Humanos , Masculino , África , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/prevención & control , Pirimidinas/uso terapéutico
5.
AIDS ; 36(2): 257-265, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34172672

RESUMEN

OBJECTIVE: Vaccine-preventable human papillomavirus (HPV) infection is common, especially in sub-Saharan Africa where HIV risk is also high. However, unlike other sexually transmitted infections (STIs), HPV's role in HIV acquisition is unclear. We evaluated this relationship using data from MTN-003, a clinical trial of HIV chemoprophylaxis among cisgender women in sub-Saharan Africa. DESIGN: A case-control study. METHODS: We matched 138 women who acquired HIV (cases) to 412 HIV-negative controls. Cervicovaginal swabs collected within 6 months before HIV seroconversion were tested for HPV DNA. We estimated the associations between carcinogenic (high-risk) and low-risk HPV types and types targeted by HPV vaccines and HIV acquisition, using conditional logistic regression models adjusted for time-varying sexual behaviors and other STIs. RESULTS: Mean age was 23 (±4) years. Any, high-risk and low-risk HPV was detected in 84, 74 and 66% of cases, and 65, 55 and 48% of controls. Infection with at least two HPV types was common in cases (67%) and controls (49%), as was infection with nonavalent vaccine-targeted types (60 and 42%). HIV acquisition increased with any [adjusted odds ratio (aOR) 2.5, 95% confidence interval (95% CI) 1.3-4.7], high-risk (aOR 2.6, 95% CI 1.5-4.6) and low-risk (aOR 1.8, 95% CI 1.1-2.9) HPV. Each additional type detected increased HIV risk by 20% (aOR 1.2, 95% CI 1.1-1.4). HIV acquisition was associated with HPV types targeted by the nonavalent (aOR 2.1, 95% CI 1.3-3.6) and quadrivalent vaccines (aOR 1.9, 95% CI 1.1-3.2). CONCLUSION: HPV infection is associated with HIV acquisition in sub-Saharan African women. In addition to preventing HPV-associated cancers, increasing HPV vaccination coverage could potentially reduce HIV incidence.


Asunto(s)
Alphapapillomavirus , Infecciones por VIH , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Adulto , Estudios de Casos y Controles , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/prevención & control , Prevalencia , Factores de Riesgo , Vacunación , Adulto Joven
6.
AIDS Behav ; 25(9): 2801-2814, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34117592

RESUMEN

Understanding characteristics associated with adherence to pre-exposure prophylaxis (PrEP) methods for HIV-1 prevention may assist with optimizing implementation efforts. The dapivirine vaginal ring is a novel topical PrEP delivery method. Using data from a randomized, double-blind, placebo-controlled, phase III trial of the dapivirine vaginal ring conducted in four African countries, generalized estimating equation models were used to evaluate correlates of ring adherence. Two levels of quarterly dapivirine blood plasma, and dapivirine released from returned rings defined measures of adherence for recent and cumulative use, respectively. Time on study, calendar time, primary partner knowledge that the participant was taking part in the study, and use of long-acting contraceptive methods were associated with ring adherence whereas younger age, ring worries, condom use, episodes of menstrual bleeding and vaginal washing were associated with non-adherence. These findings may be useful for recruitment into future clinical studies and dapivirine ring implementation efforts.


Asunto(s)
Fármacos Anti-VIH , Dispositivos Anticonceptivos Femeninos , Infecciones por VIH , VIH-1 , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Pirimidinas
7.
Sex Transm Dis ; 44(3): 135-140, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28178109

RESUMEN

BACKGROUND: In sub-Saharan Africa, there are limited data on the incidence of sexually transmitted infections (STIs) among women, largely because routine screening for asymptomatic infection is not performed. We conducted a secondary analysis to measure STI incidence rates and determine risk factors for new STI acquisition among women enrolled in the VOICE trial. METHODS: We analyzed data from 4843 women screened for chlamydia, gonorrhoea, syphilis, and trichomonas infection at baseline, annually, at interim visits when clinically indicated and at their study termination visit. Risk reduction counseling and condoms were provided throughout the trial. RESULTS: Twenty percent of evaluable participants had one or more curable STIs at baseline. Over 5660 person-years at risk (PYAR) of observation, incidence rates were 13.8% (95% confidence interval [CI], 12.7-14.8) PYAR for chlamydia, 3.5% (95% CI, 3.0-4.1) PYAR gonorrhea, 0.1% (95% CI, 0.6-1.1) PYAR syphilis, and 6.6% (95% CI, 5.8-7.2) PYAR trichomoniasis. South African sites had the highest incidence of chlamydia. The Uganda site had the highest incidence of gonorrhoea and syphilis, and Zimbabwe the lowest incidence overall. The majority of these cases were diagnosed at a routine scheduled testing visit. In multivariate analysis, positive baseline STI, younger than 25 years, being unmarried, and some alcohol consumption were associated with acquiring a new STI. CONCLUSIONS: We observed high rates of STIs during follow up among women in the VOICE study. Women living in human immunodeficiency virus endemic countries should be screened for common STIs.


Asunto(s)
Infecciones por VIH/prevención & control , Enfermedades de Transmisión Sexual/epidemiología , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Quimioprevención , Condones/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Estudios Prospectivos , Factores de Riesgo , Conducta de Reducción del Riesgo , Enfermedades de Transmisión Sexual/etiología , Enfermedades de Transmisión Sexual/prevención & control , Uganda/epidemiología , Adulto Joven , Zimbabwe/epidemiología
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