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1.
Artículo en Inglés | MEDLINE | ID: mdl-39085989

RESUMEN

BACKGROUND: Accurate HIV point of care testing is the cornerstone of prevention and treatment efforts globally, though false (both negative and positive) results are expected to occur. SETTING: We assessed the spectrum of true and false positive HIV results in a large prospective study of HIV incidence in African women using three contraceptive methods tested longitudinally in Eswatini, Kenya, South Africa, and Zambia. METHODS: HIV serologic testing was conducted quarterly using two parallel rapid HIV tests. When one or both tests were positive, additional confirmatory testing was conducted, including HIV enzyme immunoassay (EIA) and ribonucleic acid (RNA). RESULTS: 7730 women contributed 48,234 visits: true positive results occurred at 412 visits (0.9%) and false positives at 96 visits (0.2%). Of 412 women with HIV seroconversion, 10 had discordant (i.e., one negative and one positive) rapid tests and 13 had undetectable HIV RNA levels. Of 62 women with false positive rapid HIV results, most had discordant rapid testing but six (9.7%) had dually-positive rapid results and four (6.5%) had false positive or indeterminate EIA results. The positive predictive value of dual positive rapid results was 98.3%. CONCLUSION: Although the majority of rapid test results were accurate, false positive results were expected and occurred in this population of initially HIV seronegative individuals tested repeatedly and prospectively. When HIV infection occurred, not all cases had textbook laboratory results. Our findings highlight the importance of confirmatory testing, particularly for individuals undergoing repeat testing and in settings where the point prevalence is expected to be low.

2.
Curr HIV/AIDS Rep ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39052142

RESUMEN

PURPOSE OF REVIEW: This review summarizes differentiated service delivery (DSD) models for HIV treatment and prevention that have been adapted for maintaining continuity of services during the COVID-19 pandemic and proposes strategies for sustaining their benefits now and during future disruptions. RECENT FINDINGS: The COVID-19 pandemic resulted in an overburdened and disrupted health system, forcing countries to adopt and/or scale up DSD models for HIV services. While initially implemented as emergency measures, these models evolved and were refined over time to fit recipient needs ensuring continued HIV treatment and prevention services with minimal health system impact. Successful models employed task shifting, community-based delivery models, multimonth scripting and dispensing, and telehealth for remote consultation. DSD models enabled HIV services globally to be maintained during the COVID-19 pandemic. Though these models and adaptations were critical in addressing health gaps and disruptions caused by the pandemic, they were beneficial in improving efficiency and access to client-centered services and should be sustained.

3.
Lancet HIV ; 11(8): e522-e530, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38976993

RESUMEN

BACKGROUND: Adherence challenges with oral tenofovir-based pre-exposure prophylaxis (PrEP) are common. We developed a point-of-care assay to objectively assess tenofovir in urine and conducted a pilot trial examining the impact of counselling informed by use of this urine assay on long-term PrEP adherence. METHODS: This randomised trial enrolled women not in serodiscordant partnerships 3 months after PrEP initiation at the Kenya Medical Research Institute to compare standard-of-care adherence counselling versus counselling informed by the urine assay (urine-test counselling group) every 3 months for 12 months. In the standard of care group, urine samples were stored and tested at study end without participant feedback. Here we report the adherence primary outcome of hair concentrations of tenofovir at 12 months as a long-term metric (undetectable levels defined long-term non-adherence), as well as urine concentrations of tenofovir at each visit as a short-term adherence metric and acceptability of the assay assessed by quantitative surveys. Data were analysed by randomisation group. This completed trial was registered with ClinicalTrials.gov (NCT03935464). FINDINGS: From March 17, 2021 to Jan 18, 2022 we enrolled 49 women in the urine-test counselling group and 51 in the standard of care group; retention was 86 (86%) of 100. Nine (21%) of 42 in the urine-test counselling group had hair samples at 12 months with tenofovir concentrations below the limit of quantification compared with 15 (37%) of 41 in the standard of care group. The relative odds of long-term non-adherence in the standard of care group compared with urine-test counselling were 3·53 (95% CI 1·03-12·03; p=0·044). Pre-intervention, urine tenofovir was detectable in 65% in the urine-test counselling group and 71% in the standard of care group (p=0·68). At 12 months, 31 (72%) of 43 in the intervention group had detectable urine tenofovir compared with 19 (45%) of 42 in the standard of care group (p=0·0015). 40 (93%) of 43 participants liked the test very much and only one disliked the test. One participant in the standard of care group was withdrawn at the 6-month visit due to HIV seroconversion. INTERPRETATION: A low-cost urine tenofovir assay to inform PrEP counselling resulted in improvement in both short-term and long-term metrics of adherence. This urine tenofovir assay could help to improve long-term PrEP adherence. FUNDING: National Institute of Allergy and Infectious Diseases and National Institutes of Health.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Cumplimiento de la Medicación , Profilaxis Pre-Exposición , Tenofovir , Humanos , Femenino , Tenofovir/orina , Tenofovir/uso terapéutico , Tenofovir/administración & dosificación , Profilaxis Pre-Exposición/métodos , Infecciones por VIH/prevención & control , Kenia , Proyectos Piloto , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/uso terapéutico , Cumplimiento de la Medicación/estadística & datos numéricos , Sistemas de Atención de Punto , Consejo/métodos , Cabello/química , Adulto Joven , Pruebas en el Punto de Atención
4.
Front Reprod Health ; 6: 1325257, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38860025

RESUMEN

Background: Oral pre-exposure prophylaxis (PrEP) using co-formulated emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) is a potent HIV prevention method for men and women, with its efficacy highly dependent on adherence. A pivotal HIV efficacy study combined with a directly observed pharmacological study defined the thresholds for HIV protection in men who have sex with men (MSM), which are the keys to PrEP promotion and development of new PrEP agents. For African women at risk for HIV and belonging to a priority group considered due to disproportionately high incident HIV infections, the variable adherence in PrEP clinical trials and the limited pharmacologic data have resulted in a lack of clarity about the PrEP adherence required for HIV protection. We propose a study to quantify the adherence-concentration-efficacy thresholds of TDF/FTC PrEP among African cisgender women to inform decisions about optimal PrEP dosing and adherence for HIV protection. Methods: We randomized 45 low-risk HIV-uninfected African women, aged 18-30 years old, to directly observe the TDF/FTC PrEP of two, four, or seven doses per week for 8 weeks. A complementary age-matched pregnant women cohort at high risk of HIV, who will receive seven doses per week, was recruited (N = 15) with the primary aim of establishing benchmark concentrations in dried blood spots and peripheral blood mononuclear cells. Plasma, whole blood (WB), urine, hair, vaginal fluid, and vaginal tissue (non-pregnant women only) were archived for future testing. Drug concentrations were measured using methods validated for each biological matrix. Pharmacokinetic models were fitted to drug concentrations to quantify concentration-adherence thresholds. To define the drug concentrations associated with HIV protection, we applied the newly defined thresholds from the primary pharmacologic trial to the subset of women randomized to TDF/FTC or TDF in the Partners PrEP Study with the drug concentration assessed in plasma and WB samples. Multiple imputation was used to construct a data set with drug concentrations at each visit when an HIV test was performed for the entire cohort, replicating the work for MSM. Discussion: The proposed study generated the first African women-specific TDF-PrEP adherence-concentration-efficacy thresholds essential for guiding the accurate interpretation of TDF/FTC PrEP programs and clinical trials of novel HIV prevention products using TDF/FTC as an active control. Clinical Trial Registration: ClinicalTrials.gov, identifier (NCT05057858).

5.
PLoS One ; 19(3): e0299168, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38451884

RESUMEN

Real-time electronic adherence monitoring involves "smart" pill boxes that record and monitor openings as a proxy for pill taking and may be useful in understanding and supporting PrEP use; however, acceptability and/or feasibility for PrEP users is uncertain. We sought to understand the experiences of using a real-time electronic adherence monitor for PrEP delivery among young women in Kisumu and Thika, Kenya. We used the Wisepill device to monitor PrEP use among 18-24-year-old women for two years. Half of the participants were randomized to also receive SMS adherence reminders (daily or as needed for missed doses). We assessed acceptability quantitatively and qualitatively according to the four constructs of Unified Theory of Acceptance and Use of Technology (UTAUT): performance expectancy, effort expectancy, social influence, and facilitating conditions. We assessed feasibility by monitor functionality during periods of PrEP use. We analyzed quantitative data descriptively and compared by site and over time; qualitative data were analyzed inductively and deductively. The median age was 21 years (IQR 19-22), median education was 12 years (IQR 10-13), 182 (53%) had disclosed PrEP use, and 55 (16%) reported recent intimate partner violence. Most participants reported high levels of usefulness and high interest in using the monitor with few problems or worries reported throughout follow-up. Feasibility was high overall with some differences by site (96% functional monitor days in Kisumu vs 88% in Thika). Few monitors were reported lost (N = 29; 8%) or dysfunctional (N = 11; 3%). In qualitative interviews, electronic monitoring was perceived as useful because it supported privacy, confidentiality, easy storage, and PrEP adherence. Effort was generally considered low. Participants expressed some concern for stigma from monitor and/or PrEP use. Facilitating conditions involved the monitor size, color, and battery life. Overall, real-time electronic adherence monitoring was a highly acceptable and feasible approach to understand PrEP adherence among young women in a sub-Saharan African setting.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Humanos , Femenino , Adulto Joven , Adulto , Adolescente , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Profilaxis Pre-Exposición/métodos , Kenia , Estudios de Factibilidad , Fármacos Anti-VIH/uso terapéutico , Cumplimiento de la Medicación , Electrónica
6.
J Int AIDS Soc ; 27(3): e26222, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38446643

RESUMEN

INTRODUCTION: Delivery of oral pre-exposure prophylaxis (PrEP) is being scaled up in Africa, but clinic-level barriers including lengthy clinic visits may threaten client continuation on PrEP. METHODS: Between January 2020 and January 2022, we conducted a quasi-experimental evaluation of differentiated direct-to-pharmacy PrEP refill visits at four public health HIV clinics in Kenya. Two clinics implemented the intervention package, which included direct-to-pharmacy for PrEP refill, client HIV self-testing (HIVST), client navigator, and pharmacist-led rapid risk assessment and dispensing. Two other clinics with comparable size and client volume served as contemporaneous controls with the usual clinic flow. PrEP continuation was evaluated by visit attendance and pharmacy refill records, and time and motion studies were conducted to determine time spent in the clinics. Dried blood spots were collected to test for tenofovir-diphosphate (TFV-DP) at random visits. We used logistic regression to assess the intervention effect on PrEP continuation and the Wilcoxon rank sum test to assess the effect on clinic time. RESULTS: Overall, 746 clients were enrolled, 366 at control clinics (76 during pre-implementation and 290 during implementation phase), and 380 at direct-to-pharmacy clinics (116 during pre-implementation and 264 during implementation phase). Prior to implementation, the intervention and control clinics were comparable on client characteristics (female: 51% vs. 47%; median age: 33 vs. 33 years) and PrEP continuation (35% vs. 37% at 1 month, and 37% vs. 39% at 3 months). The intervention reduced total time spent at the clinic by 35% (median of 51 minutes at control vs. 33 minutes at intervention clinics; p<0.001), while time spent on HIV testing (20 vs. 20 minutes; p = 0.50) and pharmacy (8 vs. 8 minutes; p = 0.8) was unchanged. PrEP continuation was higher at intervention versus the control clinics: 45% versus 33% at month 1, 34% versus 25% at month 3 and 23% versus 16% at month 6. TFV-DP was detected in 85% (61/72) of samples, similar by the study group (83% vs. 85%). CONCLUSIONS: A client-centred PrEP delivery approach with direct-to-pharmacy PrEP refill visits plus client HIVST significantly reduced clinic visit time by more than one-third and improved PrEP continuation in public health HIV clinics in Kenya.


Asunto(s)
Adenina , Infecciones por VIH , Organofosfatos , Farmacia , Adulto , Femenino , Humanos , Adenina/análogos & derivados , Atención Ambulatoria , VIH , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Prueba de VIH , Kenia , Autoevaluación , Masculino
7.
Infect Immun ; 92(4): e0050323, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38451079

RESUMEN

Non-neutralizing functions of antibodies, including phagocytosis, may play a role in Chlamydia trachomatis (CT) infection, but these functions have not been studied and assays are lacking. We utilized a flow-cytometry-based assay to determine whether serum samples from a well-characterized cohort of CT-infected and naïve control individuals enhanced phagocytosis via Fc-receptor-expressing THP-1 cells, and whether this activity correlated with antibody titers. Fc-receptor-mediated phagocytosis was detected only in CT+ donors. Phagocytosis generally did not correlate well with antibody titer. In addition, we found that complement from both CT+ and negative individuals enhanced phagocytosis of CT into primary neutrophils. These results suggest that anti-CT antibodies can have functions that are not reflected by titer. This method could be used to quantitively measure Fc-receptor-mediated function of anti-CT antibodies or complement activity and could reveal new immune correlates of protection.


Asunto(s)
Infecciones por Chlamydia , Receptores Fc , Humanos , Fagocitosis , Neutrófilos , Anticuerpos Antibacterianos , Chlamydia trachomatis
8.
Lancet Glob Health ; 12(3): e491-e499, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38365419

RESUMEN

BACKGROUND: The first randomised controlled trial of single-dose human papillomavirus (HPV) vaccine efficacy, the Kenya single-dose HPV-vaccine efficacy (KEN SHE) trial, showed greater than 97% efficacy against persistent HPV16 and HPV18 infection at 36 months among women in Kenya. We compared antibody responses after one dose of HPV vaccine in the Dose Reduction Immunobridging and Safety Study (DoRIS), the first randomised trial of the single- dose regimen in girls aged 9-14 years, the target age range for vaccination, with those after one dose of the same vaccine in KEN SHE. METHODS: In the DoRIS trial, 930 girls aged 9-14 years in Tanzania were randomly assigned to one, two, or three doses of the 2-valent vaccine (Cervarix) or the 9-valent vaccine (Gardasil-9). The proportion seroconverting and geometric mean concentrations (GMCs) at month 24 after one dose were compared with those in women aged 15-20 years who were randomly assigned to one dose of the same vaccines at the same timepoint in KEN SHE. Batched samples were tested together by virus-like particle ELISA for HPV16 and HPV18 IgG antibodies. Non-inferiority of GMC ratios (DoRIS trial:KEN SHE) was predefined as a lower bound of the 95% CI less than 0·50. FINDINGS: Month 24 HPV16 and HPV18 antibody GMCs in DoRIS were similar or higher than those in KEN SHE. 2-valent GMC ratios were 0·90 (95% CI 0·72-1·14) for HPV16 and 1·02 (0·78-1·33) for HPV18. 9-valent GMC ratios were 1·44 (95% CI 1·14-1·82) and 1·47 (1·13-1·90), respectively. Non-inferiority of antibody GMCs and seropositivity was met for HPV16 and HPV18 for both vaccines. INTERPRETATION: HPV16 and HPV18 immune responses in young girls 24 months after a single dose of 2-valent or 9-valent HPV vaccine were comparable to those in young women who were randomly assigned to a single dose of the same vaccines and in whom efficacy had been shown. A single dose of HPV vaccine, when given to girls in the target age range for vaccination, induces immune responses that could be effective against persistent HPV16 and HPV18 infection at least two years after vaccination. FUNDING: The UK Department of Health and Social Care, the Foreign, Commonwealth, & Development Office, the Global Challenges Research Fund, the UK Medical Research Council and Wellcome Trust Joint Global Health Trials scheme, the Bill and Melinda Gates Foundation, the US National Cancer Institute; the US National Institutes of Health, and the Francis and Dorothea Reed Endowed Chair in Infectious Diseases. TRANSLATION: For the KiSwahili translation of the abstract see Supplementary Materials section.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Humanos , Femenino , Adolescente , Kenia , Tanzanía , Vacunas contra Papillomavirus/administración & dosificación , Vacunas contra Papillomavirus/inmunología , Niño , Infecciones por Papillomavirus/prevención & control , Adulto Joven , Anticuerpos Antivirales/sangre , Vacuna Tetravalente Recombinante contra el Virus del Papiloma Humano Tipos 6, 11 , 16, 18/administración & dosificación , Vacuna Tetravalente Recombinante contra el Virus del Papiloma Humano Tipos 6, 11 , 16, 18/inmunología , Papillomavirus Humano 16/inmunología , Papillomavirus Humano 18/inmunología , Esquemas de Inmunización
9.
Nat Med ; 29(12): 3224-3232, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38049621

RESUMEN

Cervical cancer burden is high where prophylactic vaccination and screening coverage are low. We demonstrated in a multicenter randomized, double-blind, controlled trial that single-dose human papillomavirus (HPV) vaccination had high vaccine efficacy (VE) against persistent infection at 18 months in Kenyan women. Here, we report findings of this trial through 3 years of follow-up. Overall, 2,275 healthy women aged 15-20 years were recruited and randomly assigned to receive bivalent (n = 760), nonavalent (n = 758) or control (n = 757) vaccine. The primary outcome was incident-persistent vaccine type-specific cervical HPV infection. The primary evaluation was superiority analysis in the modified intention-to-treat (mITT) HPV 16/18 and HPV 16/18/31/33/45/52/58 cohorts. The trial met its prespecified end points of vaccine type-specific persistent HPV infection. A total of 75 incident-persistent infections were detected in the HPV 16/18 mITT cohort: 2 in the bivalent group, 1 in the nonavalent group and 72 in the control group. Nonavalent VE was 98.8% (95% CI 91.3-99.8%, P < 0.0001) and bivalent VE was 97.5% (95% CI 90.0-99.4%, P < 0.0001). Overall, 89 persistent infections were detected in the HPV 16/18/31/33/45/52/58 mITT cohort: 5 in the nonavalent group and 84 in the control group; nonavalent VE was 95.5% (95% CI 89.0-98.2%, P < 0.0001). There were no vaccine-related severe adverse events. Three years after vaccination, single-dose HPV vaccination was highly efficacious, safe and conferred durable protection. ClinicalTrials.gov no. NCT03675256 .


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Kenia/epidemiología , Papillomaviridae , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/efectos adversos , Infección Persistente , Neoplasias del Cuello Uterino/prevención & control , Vacunación/métodos , Método Doble Ciego
10.
Front Health Serv ; 3: 1233923, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37600926

RESUMEN

Background: Cervical cancer is the leading cause of cancer-related deaths among Kenyan women. Persistent infection with high-risk oncogenic Human papillomavirus (HPV) genotypes is a necessary cause of cervical cancer. HPV vaccines are safe, durable, and efficacious in preventing incident HPV infections. In Kenya, despite efforts to increase HPV vaccination, coverage remains low. We sought to assess: (1) barriers and facilitators of HPV vaccination from the perspective of adolescent girls and young women (AGYW), their guardians as well as stakeholders involved in HPV vaccine delivery, and (2) the acceptability of the single dose of the HPV vaccination among healthcare providers (HCPs). Methods: Our study is nested within the KENya Single-dose HPV-vaccine Efficacy study (KEN SHE) that sought to test the efficacy of single-dose bivalent (HPV 16/18) and single-dose nonavalent (HPV 16/18/31/33/45/52/58/6/11) vaccination. We are conducting this study in Kiambu, Nairobi, and Kisumu counties. In these counties, we are interviewing stakeholders (n = ∼25), selected based on their role in HPV vaccination at the county and national levels. Interviews are audio recorded and conducted in English or Swahili. The semi-structured interview guides were designed based on: (1) the Theoretical Domains Framework (TDF) for AGYW and guardians and (2) the Consolidated Framework for Implementation Research (CFIR) for other stakeholders. The Theoretical Framework of Acceptability (TFA) was leveraged to design the survey administered to HCPs (n = ∼309) involved in HPV vaccination. We will develop a codebook based on emerging codes from the transcripts and constructs from the TDF and CFIR. Emerging themes will be summarized highlighting similarities and differences between and within the different stakeholder groups and counties. Descriptive statistics and a χ2 test will be used to assess the distribution of responses between the different sites and regression analysis will be used to assess factors associated with high acceptability of the single-dose strategy while controlling for confounding variables. Discussion: Our study will describe key barriers and facilitators that affect HPV vaccination from the perspective of multiple stakeholders as well as insights on the perspective of HCPs towards the single-dose strategy to inform the designing of strategies to increase HPV vaccination uptake in Kenya and comparable settings.

11.
AIDS Behav ; 27(12): 3961-3969, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37351684

RESUMEN

Understanding PrEP adherence is key in the formulation of HIV prevention strategies; however, measurement of adherence can be challenging. We compared multiple adherence measures in a two-year study of young Kenyan women at high risk of HIV acquisition. Among 289 participants, concordance between electronic adherence monitoring (EAM) and tenofovir diphosphate (TFV-DP) in dried blood spots ranged from 57 to 72% depending on selected thresholds. Using area under the receiver operating curve, discrimination of quantifiable TFV-DP was high at 0.85 with EAM and low at 0.49-0.54 for multiple self-reported measures. Correlation between EAM and self-reported measures was low (r < 0.11) although correlation within self-reported measures was moderate (r > 0.69). These findings indicate that both TFV-DP and EAM are useful PrEP adherence tools. Adherence would benefit from better availability of less expensive versions of both measurement tools. Additionally, further research on TFV-DP thresholds is needed to inform interpretation and use in understanding PrEP adherence in this population.


RESUMEN: Comprender la adherencia a la PrEP es importante en la formulación de estrategias de prevención del VIH; sin embargo, la medición de la adherencia puede ser difícil. Comparamos múltiples medidas de adherencia en un estudio de dos años de mujeres jóvenes kenianas con alto riesgo de contraer el VIH. Entre 289 participantes, la concordancia entre la monitorización electrónica de la adherencia (EAM) y el tenofovir difosfato (TFV-DP) en las manchas de sangre seca varió del 57% al 72% dependiendo de los umbrales seleccionados. Utilizando el área bajo la curva operativa del receptor, la discriminación de TFV-DP cuantificable fue alta en 0.85 con EAM y baja en 0.49­0.54 para múltiples medidas autoinformadas. La correlación entre la EAM y las medidas autoinformadas fue baja (r < 0,11), aunque la correlación entre de las medidas autoinformadas fue moderada (r > 0,69). Estos resultados indican que tanto TFV-DP como EAM son herramientas útiles de adherencia a la PrEP. La adherencia se beneficiaría de una mejor disponibilidad de versiones menos costosas de ambas herramientas de medición. Además, se necesita más investigación sobre los umbrales TFV-DP para informar la interpretación y el uso en la comprensión de la adherencia a la PrEP en esta población.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Humanos , Femenino , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Kenia/epidemiología , Cumplimiento de la Medicación
12.
Front Reprod Health ; 5: 1118030, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37383290

RESUMEN

Introduction: Globally, many young women face the overlapping burden of HIV infection and unintended pregnancy. Protection against both may benefit from safe and effective multipurpose prevention technologies. Methods: Healthy women ages 18-34 years, not pregnant, seronegative for HIV and hepatitis B surface antigen, not using hormonal contraception, and at low risk for HIV were randomized 2:2:1 to continuous use of a tenofovir/levonorgestrel (TFV/LNG), TFV, or placebo intravaginal ring (IVR). In addition to assessing genital and systemic safety, we determined TFV concentrations in plasma and cervicovaginal fluid (CVF) and LNG levels in serum using tandem liquid chromatography-mass spectrometry. We further evaluated TFV pharmacodynamics (PD) through ex vivo CVF activity against both human immunodeficiency virus (HIV)-1 and herpes simplex virus (HSV)-2, and LNG PD using cervical mucus quality markers and serum progesterone for ovulation inhibition. Results: Among 312 women screened, 27 were randomized to use one of the following IVRs: TFV/LNG (n = 11); TFV-only (n = 11); or placebo (n = 5). Most screening failures were due to vaginal infections. The median days of IVR use was 68 [interquartile range (IQR), 36-90]. Adverse events (AEs) were distributed similarly among the three arms. There were two non-product related AEs graded >2. No visible genital lesions were observed. Steady state geometric mean amount (ssGMA) of vaginal TFV was comparable in the TFV/LNG and TFV IVR groups, 43,988 ng/swab (95% CI, 31,232, 61,954) and 30337 ng/swab (95% CI, 18,152, 50,702), respectively. Plasma TFV steady state geometric mean concentration (ssGMC) was <10 ng/ml for both TFV IVRs. In vitro, CVF anti-HIV-1 activity showed increased HIV inhibition over baseline following TFV-eluting IVR use, from a median of 7.1% to 84.4% in TFV/LNG, 15.0% to 89.5% in TFV-only, and -27.1% to -20.1% in placebo participants. Similarly, anti-HSV-2 activity in CVF increased >50 fold after use of TFV-containing IVRs. LNG serum ssGMC was 241 pg/ml (95% CI 185, 314) with rapid rise after TFV/LNG IVR insertion and decline 24-hours post-removal (586 pg/ml [95% CI 473, 726] and 87 pg/ml [95% CI 64, 119], respectively). Conclusion: TFV/LNG and TFV-only IVRs were safe and well tolerated among Kenyan women. Pharmacokinetics and markers of protection against HIV-1, HSV-2, and unintended pregnancy suggest the potential for clinical efficacy of the multipurpose TFV/LNG IVR. Clinical Trial Registration: NCT03762382 [https://clinicaltrials.gov/ct2/show/NCT03762382].

13.
Am J Obstet Gynecol ; 229(3): 282.e1-282.e11, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37391005

RESUMEN

BACKGROUND: Bacterial vaginosis is a risk factor for sexually transmitted infections, including HIV. Adult African women have a high prevalence of bacterial vaginosis, but it is not known when first bacterial vaginosis occurs. OBJECTIVE: This study aimed to describe bacterial vaginosis in younger African women, before and after first sex, and to determine the incidence of bacterial vaginosis and significant correlates of bacterial vaginosis incidence and recurrence. STUDY DESIGN: In a prospective observational cohort study enrolling adolescents with limited sexual experience, young women aged 16 to 21 years were recruited in Thika, Kenya. Eligible participants were HIV and herpes simplex virus 2 seronegative and reported 0 or 1 lifetime sexual partner. The Nugent score was determined at quarterly visits from vaginal Gram stains. The trends in bacterial vaginosis were described over time; hazard ratios were calculated using Cox regression, and relative risk of bacterial vaginosis was estimated using generalized estimating equations and Poisson regression. RESULTS: A total of 400 participants with a median age of 18.6 years (interquartile range, 16-21) were enrolled. Of note, 322 participants (80.5%) reported no history of sex, whereas 78 participants (19.5%) reported sex with 1 partner. At enrollment, bacterial vaginosis (Nugent score of ≥7) was uncommon (21/375 [5.6%]). Overall, 144 participants had bacterial vaginosis at least once, for an incidence rate of 16.5 cases per 100 person-years. Before first sex, bacterial vaginosis was present at 2.8% of visits, compared with 13.7% of visits after first sex. An adjusted model of bacterial vaginosis incidence observed that first sex was associated with more than a 2-fold increased bacterial vaginosis risk (adjusted hazard ratio, 2.44; 95% confidence interval, 1.25-4.76; P=.009). Chlamydia diagnosis (adjusted hazard ratio, 1.73; 95% confidence interval, 1.1-2.8; P=.02), and herpes simplex virus 2 seropositivity (adjusted hazard ratio, 2.88; 95% confidence interval, 1.17-7.09; P=.021) were both associated with incident bacterial vaginosis. A multivariate generalized estimating equation model, including all episodes of bacterial vaginosis, demonstrated risk factors, including first sex, sexually transmitted infections, urban residence, recent sex, and no income; the most important risk factor was first sex (adjusted relative risk, 1.92; 95% confidence interval, 1.12-3.31; P=.018). The probability of bacterial vaginosis increased with each subsequent episode; mean Nugent scores increased after each bacterial vaginosis episode. CONCLUSION: Using detailed longitudinal observation, this study found that Kenyan adolescents have almost no bacterial vaginosis before first sex and that initiation of sexual activity was the strongest risk factor for both prevalent bacterial vaginosis and incident bacterial vaginosis.


Asunto(s)
Infecciones por VIH , Enfermedades de Transmisión Sexual , Vaginosis Bacteriana , Adulto , Femenino , Adolescente , Humanos , Kenia/epidemiología , Incidencia , Estudios Prospectivos , Prevalencia , Enfermedades de Transmisión Sexual/epidemiología , Vaginosis Bacteriana/epidemiología , Vaginosis Bacteriana/complicaciones , Conducta Sexual , Factores de Riesgo , Infecciones por VIH/epidemiología , Infecciones por VIH/complicaciones
14.
JAMA Netw Open ; 6(6): e2318590, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37318803

RESUMEN

Importance: Daily oral HIV preexposure prophylaxis (PrEP) delivery requires quarterly clinic visits for HIV testing and drug refilling that are costly to health systems and clients. Objective: To evaluate whether 6-month PrEP dispensing supported with interim HIV self-testing (HIVST) results in noninferior PrEP continuation outcomes at 12 months compared with standard quarterly clinic visits. Design, Setting, and Participants: This randomized noninferiority trial was conducted from May 2018 to May 2021 with 12 months of follow-up among PrEP clients aged 18 years or older who were returning for their first refill at a research clinic in Kiambu County, Kenya. Intervention: Participants were randomized 2:1 to (1) 6-month PrEP dispensing with semiannual clinic visits and interim HIVST at 3 months or (2) standard-of-care (SOC) PrEP delivery with 3-month dispensing, quarterly clinic visits, and clinic-based HIV testing. Main Outcomes and Measures: Prespecified 12-month outcomes included recent HIV testing (any in past 6 months), PrEP refilling, and PrEP adherence (detectable tenofovir-diphosphate concentrations in dried blood spots). Binomial regression models were used to estimate risk differences (RDs), and a 1-sided 95% CI lower bound (LB) of -10% or greater was interpreted as noninferior. Results: A total of 495 participants were enrolled, with 329 enrolled in the intervention group and 166 enrolled in the SOC group; 330 (66.7%) were women, 295 (59.6%) were in serodifferent relationships, and the median (IQR) age was 33 (27-40) years. At 12 months, 241 individuals in the intervention group (73.3%) and 120 in the SOC group (72.3%) returned to clinic. In the intervention group, recent HIV testing was noninferior (230 individuals [69.9%]) compared with the SOC group (116 [69.9%]; RD, -0.33%, 95% CI LB, -7.44%). PrEP refilling in the intervention group (196 [59.6%]) was inconclusive compared with the SOC group (104 [62.7%]; RD, -3.25%; 95% CI LB, -10.84%), and PrEP adherence was noninferior in the intervention group (151 [45.9%]) compared with the SOC group (70 [42.2%]; RD, 4.96%; 95% CI LB, -2.46%). No HIV seroconversions were observed over the follow-up period. Conclusions and Relevance: In this analysis of secondary trial end points at 1 year, semiannual PrEP dispensing with interim HIVST resulted in noninferior recent HIV testing and PrEP adherence compared with SOC quarterly PrEP dispensing. This novel model has the potential to optimize PrEP delivery. Trial Registration: ClinicalTrials.gov Identifier: NCT03593629.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Humanos , Femenino , Masculino , VIH , Fármacos Anti-VIH/uso terapéutico , Autoevaluación , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Kenia
15.
Contracept X ; 5: 100092, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37188149

RESUMEN

Objectives: To assess the rates of failed insertion, expulsion, and perforation when intrauterine device (IUD) insertions were done by newly trained clinicians, and to examine factors that may affect these outcomes. Study design: We evaluated skill-based outcomes following IUD insertion at 12 African sites in a secondary analysis of the Evidence for Contraceptive Options and HIV Outcomes (ECHO) randomized trial. Before trial initiation, we provided competency-based IUD training to clinicians and offered ongoing clinical support. We used Cox proportional hazards regression to examine factors associated with expulsion. Results: Among 2582 IUD acceptors who underwent first attempted IUD insertion, 141 experienced insertion failure (5.46%) and seven had uterine perforation (0.27%). Perforation was more common among breastfeeding women within three months postpartum (0.65%) compared with non-breastfeeding women (0.22%). We recorded 493 expulsions (15.5 per 100 person-years, 95% confidence interval [CI] 14.1─16.9): 383 partial and 110 complete. The risk of IUD expulsion was lower among women older than 24 years (aHR 0.63, 95% CI 0.50─0.78) and may be higher among nulliparous women. (aHR 1.65, 95% CI 0.97─2.82). Breastfeeding (aHR 0.94, 95% CI 0.72─1.22) had no significant effect on expulsion. IUD expulsion rate was highest during the first three months of the trial. Conclusions: IUD insertion failure and uterine perforation rates in our study were comparable to those reported in the literature. These results suggest that training, ongoing support, and opportunities to apply new skills were effective in ensuring good clinical outcomes for women receiving IUD insertion by newly trained providers. Implications: Data from this study support recommendations to program managers, policymakers, and clinicians that IUDs can be inserted safely in resource-constrained settings when providers receive appropriate training and support.

16.
J Adolesc Health ; 72(4): 568-574, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36658009

RESUMEN

PURPOSE: Adolescent girls and young women (AGYW) are disproportionately affected by STIs. Observation of life course events can describe behavioral and biological factors associated with STI risk. METHODS: Sexually inexperienced AGYW aged 16-20 years in Kenya were followed for five years. Quarterly visits assessed for C. trachomatis (CT), N. gonorrhea (GC), and T. vaginalis (TV), bacterial vaginosis (BV), HSV-2, and HIV. Sexual activity was self-reported but amended if incongruent with results from STI, pregnancy, or any other testing. Cox regression and Generalized Estimating Equation models were used to determine hazard ratios (HRs) and relative risks (RRs) of STI. RESULTS: During follow-up, 293 of 400 participants reported sex, 163 AGYW experienced an STI, and 72 participants had multiple STIs. Among 163 participants that experienced an STI, there were a total of 259 visits where STIs were detected, 78% (n = 201) of which included CT. Cox regression found participants with BV had over two-fold higher risk of first STI acquisition (adjusted hazard ratio (aHR): 2.35; 95% confidence interval (CI) 1.43-3.88; p = .001). Increased risk for first STI episode was associated with a new partner (aHR: 3.16; 95% CI 1.59-6.28; p = .001). AGYW who did not disclose sexual activity had the highest risk (aHR: 3.60; 95% CI 1.93-6.70; p < .001). Condom use was low, with 21% reporting condom use with sex. GEE analysis of all STIs including incident, prevalent, and recurrent, confirmed these risk factors. DISCUSSION: During the critical years after first sex, AGYW with BV, new sexual partners, and those who did not disclose sexual activity were at highest risk for STI events, especially CT.


Asunto(s)
Gonorrea , Infecciones por VIH , Enfermedades de Transmisión Sexual , Vaginosis Bacteriana , Embarazo , Adolescente , Femenino , Humanos , Incidencia , Kenia/epidemiología , Enfermedades de Transmisión Sexual/epidemiología , Conducta Sexual , Gonorrea/epidemiología , Vaginosis Bacteriana/epidemiología , Infecciones por VIH/epidemiología
17.
AIDS Behav ; 27(1): 171-181, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35841463

RESUMEN

Using data from a 2-year study of young women at high HIV risk in Thika and Kisumu, Kenya, we identified group-based trajectories of PrEP adherence based on electronic pillcap-monitoring and assessed potentially associated demographic and socio-behavioral factors. Among 348 women, we selected a three-trajectory adherence model: low and declining (N = 211, 61%), moderate but declining (N = 119, 34%) and steady high adherers (N = 18, 5%). We also identified a two-trajectory HIV risk model based on self-perceived risk in the past week: high and increasing (N = 28, 8%) and steady low (N = 320, 92%) risk. The Kisumu site was associated with the moderate but declining and steady high adherence trajectories, while increasing VOICE risk score was associated with the low and declining adherence trajectory. We found no association between the adherence and risk trajectories. Our findings suggest adherence support may need tailoring by setting. Early, sustained support may also help those at highest risk of non-adherence.


RESUMEN: Utilizando datos de un estudio de dos años de duración en mujeres jóvenes con alto riesgo de VIH en Thika y Kisumu, Kenia, identificamos trayectorias grupales de adherencia a la PrEP basadas en el monitoreo electrónico de pillcap y evaluamos los factores demográficos, sociales y de comportamiento potencialmente asociados con la adherencia. En un grupo de 348 mujeres, seleccionamos un modelo de adherencia de tres trayectorias: baja y decreciente (N = 211, 61%), moderada pero decreciente (N = 119, 34%) y altas constantes (N = 18, 5%). También identificamos un modelo de riesgo de VIH de dos trayectorias basado en el riesgo autopercibido en la última semana: riesgo alto y creciente (N = 28, 8%) y riesgo bajo constante (N = 320, 92%). El sitio de Kisumu estuvo asociado con las trayectorias de adherencia alta moderadas pero decrecientes y constantes, mientras que el aumento de la puntuación de riesgo de VOICE se asoció con la trayectoria de adherencia baja y decreciente. No se encontró asociación entre la adherencia y las trayectorias de riesgo. Nuestros hallazgos sugieren que el apoyo a la adherencia podría individualizarse de acuerdo con el entorno. El apoyo temprano y sostenido a la adherencia también puede ayudar a las personas con mayor riesgo de no adherencia.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Humanos , Femenino , Kenia/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Factores de Riesgo , Cumplimiento de la Medicación
18.
Elife ; 112022 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-36281966

RESUMEN

Background: Adolescent girls and young women (AGYW) are at high risk of sexually transmitted infections (STIs). It is unknown whether beginning to have sexual intercourse results in changes to immune mediators in the cervicovaginal tract that contribute to this risk. Methods: We collected cervicovaginal lavages from Kenyan AGYW in the months before and after first penile-vaginal sexual intercourse and measured the concentrations of 20 immune mediators. We compared concentrations pre- and post-first sex using mixed effect models. We additionally performed a systematic review to identify similar studies and combined them with our results by meta-analysis of individual participant data. Results: We included 180 samples from 95 AGYW, with 44% providing only pre-first sex samples, 35% matched pre and post, and 21% only post. We consistently detected 19/20 immune mediators, all of which increased post-first sex (p<0.05 for 13/19; Holm-Bonferroni-adjusted p<0.05 for IL-1ß, IL-2, and CXCL8). Effects remained similar after excluding samples with STIs and high Nugent scores. Concentrations increased cumulatively over time after date of first sex, with an estimated doubling time of about 5 months.Our systematic review identified two eligible studies, one of 93 Belgian participants, and the other of 18 American participants. Nine immune mediators were measured in at least two-thirds of studies. Meta-analysis confirmed higher levels post-first sex for 8/9 immune mediators (p<0.05 for six mediators, most prominently IL-1α, IL-1ß, and CXCL8). Conclusions: Cervicovaginal immune mediator concentrations were higher in women who reported that they started sexual activity. Results were consistent across three studies conducted on three different continents. Funding: This research was funded by R01 HD091996-01 (ACR), by P01 AI 030731-25 (Project 1) (AW), R01 AI116292 (FH), R03 AI154366 (FH) and by the Center for AIDS Research (CFAR) of the University of Washington/Fred Hutchinson Cancer Research Center AI027757.


Asunto(s)
Infecciones por VIH , Enfermedades de Transmisión Sexual , Adolescente , Humanos , Femenino , Coito , Estudios Prospectivos , Kenia , Interleucina-2 , Conducta Sexual , Factores Inmunológicos
19.
Contemp Clin Trials ; 122: 106935, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36162740

RESUMEN

Multipurpose prevention technology intravaginal rings (MPT IVRs) may offer a promising solution for addressing women's multiple sexual and reproductive health needs. We describe MPT IVR acceptability perspectives and examine user experiences of 25 cisgender women aged 18-34 years enrolled in a phase IIa randomized, partially blinded, placebo-controlled evaluation of tenofovir-based IVRs with and without contraceptive co-formulation. All took part in an individual, audio-recorded, semi-structured qualitative interview. A thematic analysis of transcribed interviews was completed in MaxQDA. Participants shared little to no knowledge of or experience with IVRs prior to joining the study. Four MPT IVR themes were identified: physical well-being, method reliability, personal management, and societal endorsement. Commonly cited of concern, but less described as being experienced, were physical discomforts (e.g., painful insertion/removal; inability to carry out daily activities/chores; foreign body sensation; expulsion; sexual interference, or debilitating side effects). Uncertainty regarding efficacy influenced perspectives about intended prevention benefits. Personal choices in managing reproduction and sexual behaviors had to be congruent with sociocultural values and norms for acceptance beyond the individual user level. Participants viewed broader community acceptance as likely to be mixed given community opposition to the use of modern family planning methods. They also shared concerns that IVR use could lead to infertility, especially among nulliparous women, or that it would encourage premarital sex or high-risk sexual behaviors among adolescent and young women. While a MPT IVR may not be suitable for all women, first-hand testimonials could help influence collective receptivity. Additional community acceptability research is needed. Clinical Trial Registration The study is registered at http://ClinicalTrials.gov under the identifier NCT03762382.


Asunto(s)
Dispositivos Anticonceptivos Femeninos , Infecciones por VIH , Adolescente , Femenino , Humanos , Embarazo , Infecciones por VIH/prevención & control , Reproducibilidad de los Resultados , Conducta Sexual , Tenofovir
20.
Lancet HIV ; 9(7): e464-e473, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35777410

RESUMEN

BACKGROUND: Oral pre-exposure prophylaxis (PrEP) for HIV prevention is highly effective and is being implemented at scale at health clinics throughout sub-Saharan Africa. However, barriers to clinic-based PrEP delivery remain. We aimed to establish the efficiency of semiannual PrEP clinic visits supplemented with interim home-based HIV self-testing (HIVST) versus standard of care for HIV testing, drug refilling, and adherence among PrEP users. METHODS: This was a randomised, open-label, non-inferiority trial done at the Partners in Health and Research Development clinic in Thika, Kenya. Eligible participants were HIV-negative adults (≥18 years) at risk of acquiring HIV who had started PrEP at least 1 month before enrolment. Participants were randomly assigned (1:1:1) to 6-month PrEP dispensing plus interim blood-based HIVST (with biannual clinic visits), 6-month PrEP dispensing plus interim oral fluid-based HIVST (with biannual clinic visits), or standard of care PrEP delivery (3-month PrEP dispensing with quarterly clinic visits). The three coprimary outcomes, measured at 6 months, were HIV testing (any testing between enrolment and the 6-month visit), PrEP refilling, and PrEP adherence (detectable tenofovir diphosphate concentration in dried blood spots). All analyses were done according to the intention-to-treat principle. We used binomial regression models to estimate risk differences and one-sided 95% CIs. 6-month PrEP dispensing was considered non-inferior to standard of care if the lower limit bound of the one-sided 95% CI was greater than or equal to -10%. This study is registered with ClinicalTrials.gov, NCT03593629. FINDINGS: Between May 28, 2018, and Feb 24, 2020, 495 participants were enrolled: 165 men and 130 women in HIV serodifferent couples and 200 singly enrolled women. 166 participants were randomly assigned to the standard of care group, 163 to the 6-month PrEP dispensing plus oral-fluid HIVST group, and 166 to the 6-month PrEP dispensing plus blood-based HIVST group. At 6 months, 274 (83%) of 329 participants in the combined 6-month PrEP dispensing group had tested for HIV compared with 140 (84%) of 166 participants in the standard of care group (risk difference -1·15%, 95% CI lower bound -6·89). Among participants in the combined 6-month PrEP dispensing group, 257 (78%) participants refilled PrEP compared with 134 (81%) participants in the standard of care group (-2·60%, -8·88), and 200 (61%) participants were adherent to PrEP compared with 95 (57%) participants in the standard of care group (2·37%, -5·05). No participants acquired HIV during the study. INTERPRETATION: 6-month PrEP dispensing with HIVST for interim testing reduced the number of PrEP clinic visits in half without compromising HIV testing, retention, or adherence. FUNDING: US National Institute of Mental Health.


Asunto(s)
Infecciones por VIH , Profilaxis Pre-Exposición , Adulto , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Prueba de VIH , Humanos , Kenia/epidemiología , Masculino , Autoevaluación , Estados Unidos
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