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1.
J Acquir Immune Defic Syndr ; 72(3): 333-43, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-26918545

RESUMEN

OBJECTIVE: To develop and validate an HIV risk assessment tool to predict HIV acquisition among African women. DESIGN: Data were analyzed from 3 randomized trials of biomedical HIV prevention interventions among African women (VOICE, HPTN 035, and FEM-PrEP). METHODS: We implemented standard methods for the development of clinical prediction rules to generate a risk-scoring tool to predict HIV acquisition over the course of 1 year. Performance of the score was assessed through internal and external validations. RESULTS: The final risk score resulting from multivariable modeling included age, married/living with a partner, partner provides financial or material support, partner has other partners, alcohol use, detection of a curable sexually transmitted infection, and herpes simplex virus 2 serostatus. Point values for each factor ranged from 0 to 2, with a maximum possible total score of 11. Scores ≥5 were associated with HIV incidence >5 per 100 person-years and identified 91% of incident HIV infections from among only 64% of women. The area under the curve (AUC) for predictive ability of the score was 0.71 (95% confidence interval [CI]: 0.68 to 0.74), indicating good predictive ability. Risk score performance was generally similar with internal cross-validation (AUC = 0.69; 95% CI: 0.66 to 0.73) and external validation in HPTN 035 (AUC = 0.70; 95% CI: 0.65 to 0.75) and FEM-PrEP (AUC = 0.58; 95% CI: 0.51 to 0.65). CONCLUSIONS: A discrete set of characteristics that can be easily assessed in clinical and research settings was predictive of HIV acquisition over 1 year. The use of a validated risk score could improve efficiency of recruitment into HIV prevention research and inform scale-up of HIV prevention strategies in women at highest risk.


Asunto(s)
Investigación Empírica , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , VIH-1 , Medición de Riesgo/métodos , Adulto , África/epidemiología , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Humanos , Incidencia , Masculino , Valor Predictivo de las Pruebas , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Parejas Sexuales
2.
N Engl J Med ; 372(6): 509-18, 2015 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-25651245

RESUMEN

BACKGROUND: Reproductive-age women need effective interventions to prevent the acquisition of human immunodeficiency virus type 1 (HIV-1) infection. METHODS: We conducted a randomized, placebo-controlled trial to assess daily treatment with oral tenofovir disoproxil fumarate (TDF), oral tenofovir-emtricitabine (TDF-FTC), or 1% tenofovir (TFV) vaginal gel as preexposure prophylaxis against HIV-1 infection in women in South Africa, Uganda, and Zimbabwe. HIV-1 testing was performed monthly, and plasma TFV levels were assessed quarterly. RESULTS: Of 12,320 women who were screened, 5029 were enrolled in the study. The rate of retention in the study was 91% during 5509 person-years of follow-up. A total of 312 HIV-1 infections occurred; the incidence of HIV-1 infection was 5.7 per 100 person-years. In the modified intention-to-treat analysis, the effectiveness was -49.0% with TDF (hazard ratio for infection, 1.49; 95% confidence interval [CI], 0.97 to 2.29), -4.4% with TDF-FTC (hazard ratio, 1.04; 95% CI, 0.73 to 1.49), and 14.5% with TFV gel (hazard ratio, 0.85; 95% CI, 0.61 to 1.21). In a random sample, TFV was detected in 30%, 29%, and 25% of available plasma samples from participants randomly assigned to receive TDF, TDF-FTC, and TFV gel, respectively. Independent predictors of TFV detection included being married, being older than 25 years of age, and being multiparous. Detection of TFV in plasma was negatively associated with characteristics predictive of HIV-1 acquisition. Elevations of serum creatinine levels were seen more frequently among participants randomly assigned to receive oral TDF-FTC than among those assigned to receive oral placebo (1.3% vs. 0.2%, P=0.004). We observed no significant differences in the frequencies of other adverse events. CONCLUSIONS: None of the drug regimens we evaluated reduced the rates of HIV-1 acquisition in an intention-to-treat analysis. Adherence to study drugs was low. (Funded by the National Institutes of Health; VOICE ClinicalTrials.gov number, NCT00705679.).


Asunto(s)
Adenina/análogos & derivados , Antirretrovirales/administración & dosificación , Desoxicitidina/análogos & derivados , Infecciones por VIH/prevención & control , VIH-1 , Organofosfonatos/administración & dosificación , Profilaxis Pre-Exposición , Adenina/administración & dosificación , Adenina/efectos adversos , Adenina/sangre , Administración Intravaginal , Administración Oral , Adolescente , Adulto , África del Sur del Sahara , Antirretrovirales/efectos adversos , Antirretrovirales/sangre , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/sangre , Farmacorresistencia Viral , Quimioterapia Combinada , Emtricitabina , Femenino , Infecciones por VIH/complicaciones , Seropositividad para VIH , VIH-1/efectos de los fármacos , Humanos , Cumplimiento de la Medicación , Persona de Mediana Edad , Organofosfonatos/efectos adversos , Organofosfonatos/sangre , Encuestas y Cuestionarios , Tenofovir , Adulto Joven
3.
J Adolesc Health ; 54(6): 654-62, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24690188

RESUMEN

PURPOSE: This article explores the ethics and feasibility of enrolling adolescent females in microbicide trials using data from 16- to 17-year-old participants of the Phase 3 trial of the candidate vaginal microbicide, Carraguard. METHODS: Secondary analysis was conducted to compare health, behavioral, and operational outcomes between 16- to 17-year-olds and 18- to 19-year-olds screened for and enrolled in the trial. Analytical approaches included Kaplan-Meier survival analysis, Cox proportional hazards modeling, and generalized estimating equations for nonsurvival end points. RESULTS: Results reveal no significant differences between the two age groups for health (sexually transmitted infection, adverse event), risk behavior, or operational (adherence, follow-up) outcomes. However, data suggest that after 1 year of trial participation, human immunodeficiency virus (HIV) and pregnancy incidence were higher and increased more rapidly for the 16- to 17-year-olds than for 18- to 19-year-olds; this finding is entirely consistent with other incidence data for HIV infection among South African youth and cannot be attributed to study participation without a comparison outside the trial. CONCLUSIONS: Data from the Carraguard trial provide no evidence that inclusion of 16- to 17-year-olds in the trial had any detrimental effect on trial participants or on the conduct of research. These data provide an argument motivating the inclusion of sexually active adolescents aged 16-17 years into future trials in order to avoid delaying access to an effective product for adolescents at high risk of HIV acquisition. Careful support for adolescent-inclusive protocols (including appropriate counseling) must be incorporated into study design.


Asunto(s)
Antiinfecciosos/administración & dosificación , Medicina Basada en la Evidencia/métodos , Infecciones por VIH/epidemiología , Sujetos de Investigación/estadística & datos numéricos , Conducta Sexual/estadística & datos numéricos , Enfermedades de Transmisión Sexual/epidemiología , Administración Intravaginal , Adolescente , Conducta del Adolescente , Adulto , Factores de Edad , Medicina Basada en la Evidencia/ética , Estudios de Factibilidad , Femenino , Humanos , Estimación de Kaplan-Meier , Selección de Paciente/ética , Embarazo , Embarazo en Adolescencia/estadística & datos numéricos , Modelos de Riesgos Proporcionales , Asunción de Riesgos , Sudáfrica/epidemiología , Resultado del Tratamiento , Adulto Joven
4.
Soc Sci Med ; 110: 49-55, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24721447

RESUMEN

In a context of high rates of intimate partner violence (IPV), trials of female-controlled technologies for HIV prevention such as microbicides may increase the possibility of social harms. Seeking to explore the relationship between IPV and microbicide use further, this paper documents women's narratives of participating in the Microbicide Development Program (MDP) trial in Johannesburg, South Africa, and experiences of partner violence and conflict. A social science sub-study, nested within the trial, was conducted between September 2005 and August 2009, and 401 serial in-depth-interviews were undertaken with 150 women. Using coded interview transcripts, we describe the distribution of IPV and the possible association thereof with microbicide gel use and trial participation. More than a third of these 150 women reported IPV, of which half the cases were related to involvement in the trial. In their narratives, those women reporting IPV cast their partners as authoritarian, controlling and suspicious and reported verbal abuse, abandonment, and in some cases, beatings. Shared experiences of everyday violence shaped women's feelings of unease about revealing their participation in the trial to intimate partners and attempted concealment further contributed to strains and conflict within relationships. Our findings point to the role of social scientific enquiry in identifying the less obvious, hidden negative impacts of participation in a clinical trial therefore exposing limitations in the biomedical construction of 'social harms', as well as the implications thereof for potential future use outside the clinical trial setting.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/prevención & control , Maltrato Conyugal/estadística & datos numéricos , Adolescente , Adulto , Fármacos Anti-VIH/efectos adversos , Método Doble Ciego , Femenino , Humanos , Narración , Investigación Cualitativa , Sudáfrica , Cremas, Espumas y Geles Vaginales/efectos adversos , Cremas, Espumas y Geles Vaginales/uso terapéutico , Adulto Joven
5.
AIDS Behav ; 15(2): 407-21, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20886278

RESUMEN

Misreporting of adherence undermines detection of an association between product use and HIV infection in microbicide trials. This study investigates whether, in a placebo trial, audio computer-assisted self-interviewing (ACASI) produces more accurate reporting of adherence and sexual behavior than a face-to-face interview (FTFI). At three South African clinics, 849 women were enrolled and instructed to use applicators filled with placebo gel; participants were randomly assigned to FTFI or ACASI. Behavioral reports were validated through two biomarkers that detect product usage and unprotected sex. For most behaviors, ACASI generated significantly higher reporting, although differences by interview mode appeared to diminish over time. ACASI participants were more likely to report having had sex without gel, but reported and tested applicators did not indicate greater honesty about gel insertion with ACASI. While comparisons of reported unprotected sex with the validated biomarker revealed more agreement with ACASI than with FTFI, differences were small.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Infecciones por VIH/prevención & control , Entrevistas como Asunto , Autorrevelación , Conducta Sexual , Administración Intravaginal , Adolescente , Adulto , Biomarcadores/análisis , Computadores , Femenino , Infecciones por VIH/diagnóstico , Humanos , Entrevistas como Asunto/métodos , Cooperación del Paciente/estadística & datos numéricos , Asunción de Riesgos , Autoevaluación (Psicología) , Factores Socioeconómicos , Sudáfrica , Encuestas y Cuestionarios , Adulto Joven
6.
Lancet ; 376(9749): 1329-37, 2010 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-20851460

RESUMEN

BACKGROUND: Innovative prevention strategies for HIV-1 transmission are urgently needed. PRO2000 vaginal gel was efficacious against HIV-1 transmission in studies in macaques; we aimed to assess efficacy and safety of 2% and 0·5% PRO2000 gels against vaginal HIV-1 transmission in women in sub-Saharan Africa. METHODS: Microbicides Development Programme 301 was a phase 3, randomised, double-blind, parallel-group trial, undertaken at 13 clinics in South Africa, Tanzania, Uganda, and Zambia. We randomly assigned sexually active women, aged 18 years or older (≥16 years in Tanzania and Uganda) without HIV-1 infection in a 1:1:1 ratio to 2% PRO2000, 0·5% PRO2000, or placebo gel groups for 52 weeks (up to 104 weeks in Uganda). Randomisation was done by computerised random number generator. Investigators and participants were masked to group assignment. The primary efficacy outcome was incidence of HIV-1 infection before week 52, which was censored for pregnancy and excluded participants without HIV-1 follow-up data or with HIV-1 infection at enrolment. HIV-1 status was established by rapid tests or ELISA at screening at 12 weeks, 24 weeks, 40 weeks, and 52 weeks, and confirmed in a central reference laboratory. The primary safety endpoint was an adverse event of grade 3 or worse. Use of 2% PRO2000 gel was discontinued on Feb 14, 2008, on the recommendation of the Independent Data Monitoring Committee because of low probability of benefit. This trial is registered at http://isrctn.org, number ISRCTN 64716212. FINDINGS: We enrolled 9385 of 15 818 women screened. 2591 (95%) of 2734 participants enrolled to the 2% PRO2000 group, 3156 (95%) of 3326 in the 0·5% PRO2000 group, and 3112 (94%) of 3325 in the placebo group were included in the primary efficacy analysis. Mean reported gel use at last sex act was 89% (95% CI 86-91). HIV-1 incidence was much the same between groups at study end (incidence per 100 woman-years was 4·5 [95% CI 3·8-5·4] for 0·5% PRO2000 vs 4·3 [3·6-5·2] for placebo, hazard ratio 1·05 [0·82-1·34], p=0·71), and at discontinuation (4·7 [3·8-5·8] for 2% PRO2000 gel, 3·9 [3·0-4·9] for 0·5% PRO2000 gel, and 3·9 [3·1-5·0] for placebo gel). Incidence of the primary safety endpoint at study end was 4·6 per 100 woman-years (95% CI 3·9-5·4) in the 0·5% PRO2000 group and 3·9 (3·2-4·6) in the placebo group; and was 4·5 (3·7-5·5) in the 2% PRO2000 group at discontinuation. INTERPRETATION: Although safe, 0·5% PRO2000 and 2% PRO2000 are not efficacious against vaginal HIV-1 transmission and are not indicated for this use. FUNDING: UK Department for International Development, UK Medical Research Council, European and Developing Countries Clinical Trials Partnership, International Partnership for Microbicides, and Endo Pharmaceuticals Solutions.


Asunto(s)
Antivirales/administración & dosificación , Infecciones por VIH/prevención & control , VIH-1 , Naftalenosulfonatos/administración & dosificación , Polímeros/administración & dosificación , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Condones/estadística & datos numéricos , Método Doble Ciego , Femenino , Infecciones por VIH/epidemiología , Humanos , Persona de Mediana Edad , Naftalenosulfonatos/efectos adversos , Polímeros/efectos adversos , Conducta Sexual , Enfermedades de Transmisión Sexual/prevención & control , Cremas, Espumas y Geles Vaginales/efectos adversos , Adulto Joven
7.
AIDS Res Ther ; 7: 10, 2010 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-20416063

RESUMEN

BACKGROUND: South Africa, with its scientific capacity, good infrastructure and high HIV incidence rates, is ideally positioned to conduct large-scale HIV prevention trials. The HIV Prevention Research Unit of the South African Medical Research Council conducted four phase III and one phase IIb trials of women-initiated HIV prevention options in KwaZulu-Natal between 2003 and 2009. A total of 7046 women participated, with HIV prevalence between 25% and 45% and HIV incidence ranging from 4.5-9.1% per year. Unfortunately none of the interventions tested had any impact on reducing the risk of HIV acquisition; however, extremely valuable experience was gained, lessons learned and capacity built, while the communities gained associated benefits. EXPERIENCE: Our experience in conducting these trials ranged from setting up community partnerships to developing clinical research sites and dissemination of trial results. Community engagement included setting up community-based research sites with approval from both political and traditional leaders, and developing community advisory groups to assist with the research process. Community-wide education on HIV/sexually transmitted infection prevention, treatment and care was provided to over 90,000 individuals. Myths and misconceptions were addressed through methods such as anonymous suggestion boxes in clinic waiting areas and intensive education and counselling. Attempts were made to involve male partners to foster support and facilitate recruitment of women. Peer educator programmes were initiated to provide ongoing education and also to facilitate recruitment of women to the trials. Recruitment strategies such as door-to-door recruitment and community group meetings were initiated. Over 90% of women enrolled were retained. Community benefits from the trial included education on HIV prevention, treatment and care and provision of ancillary care (such as Pap smears, reproductive health care and referral for chronic illnesses). Social benefits included training of home-based caregivers and sustainable ongoing HIV prevention education through peer educator programmes. CHALLENGES: Several challenges were encountered, including manipulation by participants of their eligibility criteria in order to enroll in the trial. Women attempted to co-enroll in multiple trials to benefit from financial reimbursements and individualised care. The trials became ethically challenging when participants refused to take up referrals for care due to stigma, denial of their HIV status and inadequate health infrastructure. Lack of disclosure of HIV status to partners and family members was particularly challenging. Some of the ethical dilemmas put to the test our responsibility as researchers and our obligation to provide health care to research participants. CONCLUSION: Conducting these five trials in a period of six years provided us with invaluable insights into trial implementation, community participation, recruitment and retention, provision of care and dissemination of trial results. The critical mass of scientists trained as clinical trialists will continue to address the relentless HIV epidemic in our setting and ensure our commitment to finding a biomedical HIV prevention option for women in the future.

8.
Lancet ; 372(9654): 1977-87, 2008 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-19059048

RESUMEN

BACKGROUND: Female-initiated HIV-prevention options, such as microbicides, are urgently needed. We assessed Carraguard, a carrageenan-based compound developed by the Population Council, for its efficacy and long-term safety in prevention of HIV infection in women. METHODS: We undertook a randomised, placebo-controlled, double-blind trial in three South African sites in sexually-active, HIV-negative women, aged 16 years and older. 6202 participants, who were randomly assigned by a block randomisation scheme to Carraguard (n=3103) or placebo (methylcellulose [n=3099]), were instructed to use one applicator of gel plus a condom during each vaginal sex act. Participants were followed up for up to 2 years. Visits every 3 months included testing for HIV presence and pregnancy, pelvic examinations, risk reduction counselling, and treatment for curable sexually transmitted infections and symptomatic vaginal infections. The primary outcome was time to HIV seroconversion. Analysis was in the efficacy population (a subset of the intention-to-treat population, excluding participants for whom efficacy could not be assessed). This study is registered with ClinicalTrials.gov, number NCT00213083. FINDINGS: For the primary outcome (time to HIV seroconversion) we analysed 3011 women in the Carraguard group and 2994 in the placebo group. HIV incidence was 3.3 per 100 woman-years (95% CI 2.8-3.9) in the Carraguard group (134 events) and 3.8 per 100 woman-years (95% CI 3.2-4.4) in the placebo group (151 events), with no significant difference in the distribution of time to seroconversion (p=0.30). The covariate-adjusted hazard ratio was 0.87 (95% CI 0.69-1.09). Rates of self-reported gel use (96.2% Carraguard, 95.9% placebo) and condom use (64.1% in both groups) at last sex acts were similar in both groups. On the basis of applicator testing, however, gel was estimated to have been used in only 42.1% of sex acts, on average (41.1% Carraguard, 43.1% placebo). 1420 (23%) women in the intention-to-treat population had adverse events (713 Carraguard, 707 placebo), and 95 (2%) women had adverse events that were related to gel use (48 Carraguard, 47 placebo). Serious adverse events occurred in 72 (2%) women in the Carraguard group and 78 (3%) in the placebo group, only one of which was considered possibly related to gel use (placebo group). INTERPRETATION: This study did not show Carraguard's efficacy in prevention of vaginal transmission of HIV. No safety concerns were recorded.


Asunto(s)
Infecciones por VIH/prevención & control , Cremas, Espumas y Geles Vaginales/uso terapéutico , Salud de la Mujer , Adolescente , Adulto , Carragenina/química , Química Farmacéutica , Método Doble Ciego , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Humanos , Incidencia , Conducta Sexual , Sudáfrica/epidemiología , Cremas, Espumas y Geles Vaginales/efectos adversos , Adulto Joven
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