Development of HIV-1 prevention methods is a global priority. In this randomized, controlled trial in sub-Saharan Africa, a vaginal ring containing the antiretroviral dapivirine was 27% effective in ...protecting against HIV-1 acquisition.
More than half of the 35 million persons currently living with human immunodeficiency virus type 1 (HIV-1) infection are women. A majority of these women reside in sub-Saharan Africa,
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a region that has some of the highest incidences of HIV-1 infection in any population worldwide.
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The use of antiretroviral medications as pre-exposure prophylaxis is a promising approach to the prevention of HIV-1 acquisition.
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Several clinical trials of the antiretroviral tenofovir showed such protection against HIV-1.
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However, in three trials involving African women, adherence to tenofovir-containing pills and vaginal gels was low, and HIV-1 protection was not shown. . . .
Persistent use of HIV prevention methods can be a challenge, particularly for some younger women. The long-acting, discreet, woman-centric dapivirine vaginal ring offers promise as a prevention ...method with less user burden, which could support continued use. We assessed dapivirine vaginal ring use to understand adherence patterns and identify characteristics influencing patterns.
Participants enrolled in South Africa in the MTN-020/ASPIRE randomized placebo-controlled trial.
We used group-based trajectory modeling to identify clusters of participants with similar longitudinal patterns of adherence in the last year of participation and potential predictors of group membership. Women with at least 1 year of follow-up were included (n = 626).
Five adherence patterns were identified: (1) consistently high, 34%, (2) consistently moderate, 34%, (3) consistently low, 16%, (4) decreasing, 9%, and (5) increasing, 7%. Women younger than 22 years adjusted odds ratio (AOR) 1.8, 95% confidence interval (CI): 1.0 to 3.0, using an intrauterine device (AOR 3.3, 95% CI: 1.4 to 7.8) or oral contraceptives (AOR 3.9, 95% CI: 1.7 to 8.9), experiencing menses (AOR 1.8, 95% CI: 1.1 to 3.0), and who reported inconsistent condom use (AOR 1.8, 95% CI: 1.0 to 3.3) were more likely to be classified as consistently low compared to consistently high (referent).
Most South African women successfully persisted with a moderate or high level of use. Encouraging ring replacement with completion of menses may help to decrease concerns about hygiene and improve persistence. Associations between contraception and persistent low adherence suggest efforts may be needed to ensure contraceptive method choice does not interfere with ring use.
The Antibody Mediated Prevention (AMP) trials (NCT02716675 and NCT02568215) demonstrated that passive administration of the broadly neutralizing monoclonal antibody VRC01 could prevent some HIV-1 ...acquisition events. Here, we use mathematical modeling in a post hoc analysis to demonstrate that VRC01 influenced viral loads in AMP participants who acquired HIV. Instantaneous inhibitory potential (IIP), which integrates VRC01 serum concentration and VRC01 sensitivity of acquired viruses in terms of both IC50 and IC80, follows a dose-response relationship with first positive viral load (p = 0.03), which is particularly strong above a threshold of IIP = 1.6 (r = -0.6, p = 2e-4). Mathematical modeling reveals that VRC01 activity predicted from in vitro IC80s and serum VRC01 concentrations overestimates in vivo neutralization by 600-fold (95% CI: 300-1200). The trained model projects that even if future therapeutic HIV trials of combination monoclonal antibodies do not always prevent acquisition, reductions in viremia and reservoir size could be expected.
The antibody-mediated prevention (AMP) studies (HVTN 703/HPTN 081 and HVTN 704/HPTN 085) are harmonized phase 2b trials to assess HIV prevention efficacy and safety of intravenous infusion of ...anti-gp120 broadly neutralizing antibody VRC01. Antibodies for other indications can elicit infusion-related reactions (IRRs), often requiring premedication and limiting their application. We report on AMP study IRRs.
From 2016 to 2018, 2699 HIV-uninfected, at-risk men and transgender adults in the Americas and Switzerland (704/085) and 1924 at-risk heterosexual women in sub-Saharan Africa (703/081) were randomized 1:1:1 to VRC01 10 mg/kg, 30 mg/kg, or placebo. Participants received infusions every 8 weeks (n = 10/participant) over 72 weeks, with 104 weeks of follow-up. Safety assessments were conducted before and after infusion and at noninfusion visits. A total of 40,674 infusions were administered.
Forty-seven participants (1.7%) experienced 49 IRRs in 704/085; 93 (4.8%) experienced 111 IRRs in 703/081 (P < 0.001). IRRs occurred more frequently in VRC01 than placebo recipients in 703/081 (P < 0.001). IRRs were associated with atopic history (P = 0.046) and with younger age (P = 0.023) in 703/081. Four clinical phenotypes of IRRs were observed: urticaria, dyspnea, dyspnea with rash, and "other." Urticaria was most prevalent, occurring in 25 (0.9%) participants in 704/085 and 41 (2.1%) participants in 703/081. Most IRRs occurred with the initial infusion and incidence diminished through the last infusion. All reactions were managed successfully without sequelae.
IRRs in the AMP studies were uncommon, typically mild or moderate, successfully managed at the research clinic, and resolved without sequelae. Analysis is ongoing to explore potential IRR mechanisms.
The ambitious goal to eliminate new pediatric HIV infections by 2030 requires accelerated prevention strategies in high-risk settings such as South Africa. One approach could be pre-exposure ...prophylaxis (PrEP) with broadly neutralizing anti-HIV-1 monoclonal antibodies (bNAbs). The aim of our study is to define the optimal dose(s), the ideal combination(s) of bNAbs in terms of potency and breadth, and timing of subcutaneous (SC) administration(s) to prevent breast milk transmission of HIV. Two bNAbs, CAP256V2LS and VRC07-523LS, will be assessed in a sequential and randomized phase I, single-site, single-blind, dose-finding trial. We aim to investigate the 28-day safety and pharmacokinetics (PK) profile of incrementally higher doses of these bNAbs in breastfeeding HIV-1 exposed born without HIV neonates alongside standard of care antiretroviral (ARV) medication to prevent (infants) or treat (mothers) HIV infection. The results of this trial will guide further studies on bNAbs to prevent breast milk transmission of HIV.
We evaluated the acceptability of the 25 mg dapivirine vaginal ring (DVR) as an HIV prevention intervention and its influence on DVR adherence in the MTN-020/ASPIRE phase III trial. Acceptability ...measures were captured using ACASI at month 3 and end of product use (median 24 months, IQR 15–30). Monthly returned rings were classified as nonadherent if dapivirine release rate was ≤ 0.9 mg/month. Associations between acceptability measures and nonadherence were estimated using Poisson regression models with robust standard errors. At month 3 (N = 2334), 88% reported DVR was comfortable, 80% were unaware of it during daily activities, and 74% never felt it during sex. At exit, 66% were ‘very likely’ to use DVR in the future. Acceptability was found to differ significantly by country across several measures including wearing the ring during sex, during menses, partner acceptability, impact on sexual pleasure and willingness to use the ring in the future. Risk of nonadherence at month 12 was elevated if DVR was felt during sex at month 3 (aRR 1.67, 95% CI 1.26, 2.23). Risk of nonadherence in the last year of study participation was elevated if, at exit, participants minded wearing during sex (aRR 2.08, 95% CI 1.52, 2.85), during menses (aRR 1.57, 95% CI 1.06, 2.32), reported a problematic change to the vaginal environment (aRR 1.57, 95% CI 1.12, 2.21), and were not “very likely” to use DVR in the future (aRR 1.31, 95% CI 1.02, 1.68). DVR acceptability was overall high yet varied by country. Addressing perceived ring interference with sex, menses, or problematic changes to the vaginal environment in future interventions could help improve adherence, as could embracing sex-positive messaging related to ring use and increased pleasure.
Trial Registration
ClinicalTrials.gov Identifier: NCT01617096.
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.
Gender roles and imbalances in sexual power contribute to the heightened HIV-1 risk faced by women in Sub-Saharan Africa. This has led prevention research to focus on the development of female ...controlled methods. Despite the design of products such as vaginal rings to be used autonomously by women, male partners and women’s perceptions of relationships influence HIV prevention choices. To understand the influences that male partners and dyadic dynamics had on the use of the Dapivirine Vaginal Ring in the ASPIRE trial, this analysis of qualitative data explored the types of intimate partner relationships that women engaged in. This paper describes how partners facilitated or challenged women’s ring use and how women dealt with these challenges within six different types of relationships characterized by power dynamics and commitment levels. We offer insights into how future use of female-initiated HIV prevention products can be promoted through recognition of different relationship types.
We analyzed data from 1428 users of the dapivirine vaginal ring, who participated in the MTN-020/ASPIRE phase III trial and subsequent open-label extension MTN-025/HOPE trial, to examine ...relationships between perceived ring protection, social disclosures, and self-reported ring adherence. In HOPE, 77% perceived the ring to be highly effective, and this view was associated with speaking: (a) to a greater number of people about the study, (b) with other participants, (c) to more people who were in favor of the ring, and (d) to more people whose opinions were valued. Reported adherence was not directly associated with perceived protection but was associated with disclosing to someone who was in favor of the ring. These findings suggest the importance of women’s internalized ideas about the protective benefits of the DVR in sharing information about the ring and the importance of social support on adherence.
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