Trial participation disclosure and gel use behavior in the CAPRISA 004 tenofovir gel trial

A phase I study to assess safety, pharmacokinetics, and pharmacodynamics of a vaginal insert containing tenofovir alafenamide and elvitegravir

Background

New multi-purpose prevention technology (MPT) products are needed to prevent human immunodeficiency virus (HIV) and herpes simplex virus type 2 (HSV2). In this study, we evaluated a fast-dissolve insert that may be used vaginally or rectally for prevention of infection.

Objective

To describe the safety, acceptability, multi-compartment pharmacokinetics (PK), and in vitro modeled pharmacodynamics (PD) after a single vaginal dose of an insert containing tenofovir alafenamide (TAF) and elvitegravir (EVG) in healthy women.

Methods

This was a Phase I, open-label, study. Women (n=16) applied one TAF (20mg)/EVG (16mg) vaginal insert and were randomized (1:1) to sample collection time groups for up to 7 days post dosing. Safety was assessed by treatment-emergent adverse events (TEAEs). EVG, TAF and tenofovir (TFV) concentrations were measured in plasma, vaginal fluid and tissue, and TFV-diphosphate (TFV-DP) concentration in vaginal tissue. PD was modeled in vitro by quantifying the change in inhibitory activity of vaginal fluid and vaginal tissue against HIV and HSV2 from baseline to after treatment. Acceptability data was collected by a quantitative survey at baseline and post treatment.

Results

The TAF/EVG insert was safe, with all TEAEs graded as mild, and acceptable to participants. Systemic plasma exposure was low, consistent with topical delivery, while high mucosal levels were detected, with median TFV vaginal fluid concentrations exceeding 200,000 ng/mL and 1,000 ng/mL for up to 24 hours and 7 days post dosing, respectively. All participants had vaginal tissue EVG concentrations of > 1 ng/mg at 4 and 24 hours post dosing. The majority had tissue TFV-DP concentrations exceeding 1000 fmol/mg by 24 - 72 hours post dosing. Vaginal fluid inhibition of HIV-1 and HSV-2 in vitro significantly increased from baseline and was similarly high at 4 and 24 hours post dosing. Consistent with high tissue TFV-DP concentrations, p24 HIV antigen production from ectocervical tissues infected ex vivo with HIV-1 significantly decreased from baseline at 4 hours post dosing. HSV-2 production from tissue also decreased post treatment.

Conclusions

A single dose of TAF/EVG inserts met PK benchmarks, with PK data supporting an extended window of high mucosal protection. PD modeling supports mucosal protection against both HIV-1 and HSV-2. The inserts were safe and highly acceptable.

Clinical trial registration

ClinicalTrials.gov, identifier NCT03762772.

"I didn't support PrEP because I didn't know what it was": Inadequate information undermines male partner support for young women's pre-exposure prophylaxis use in western Kenya

The HIV infection rate is higher among adolescent girls and young women (AGYW) in Africa than men in the same age range. Pre-exposure prophylaxis (PrEP) can be used by women discreetly; however, for most AGYW, male partner approval is desired. We explored PrEP use in the context of relationship violence and power dynamics through focus group discussions and support club sessions with AGYW, in-depth interviews and male sensitisation sessions with male partners of AGYW, and joint sessions with AGYW and their male partners. Many male partners reported hesitancy in supporting partner's PrEP use without sufficient information; most of these became supportive following their engagement in study activities; and most preferred participation in decisions around PrEP use. For AGYW, male involvement minimised partner violence around their PrEP use. The findings support the need for correct PrEP information to be provided to male partners of AGYW and to involve them early on, in decision-making about PrEP use. This is likely to improve uptake of and adherence to PrEP.

Disclosure of PrEP use by young women in South Africa and Tanzania: qualitative findings from a demonstration project

Investigating how young women disclose oral pre-exposure prophylaxis (PrEP) use is important given evidence that disclosure is associated with higher adherence. We report qualitative results on PrEP disclosure among young women in South Africa and Tanzania who participated in a PrEP demonstration project (EMPOWER). In total, 81 in-depth interviews were conducted with 39 young women aged 16-24 years-25 from Johannesburg and 14 from Mwanza-at approximately 3, 6 and/or 9 months post-enrolment. Analysis of data was thematic and inductive. Most Johannesburg participants were students in the inner-city; in Mwanza, all worked in recreational venues, occasionally engaging in sexual transactions with customers. A continuum of approaches was evident. Partner disclosure was common in Johannesburg but less so in Mwanza, where many partners were feared as judgemental and potentially violent. In both sites, participants commonly disclosed to family to secure support, and to friends and work colleagues to advocate about PrEP and encourage uptake among at-risk peers. Adherence clubs appeared helpful in building participants' skills and confidence to disclose, particularly in gender-inequitable sexual relationships. PrEP counselling for young women should focus on strengthening communication skills and helping develop strategies for safe disclosure.

Brief Report: Phase IIa Safety Study of a Vaginal Ring Containing Dapivirine in Adolescent Young Women

BACKGROUND

Young women aged 15-24 years are disproportionately affected by the HIV epidemic. Two phase III trials of a vaginal ring containing 25-mg dapivirine demonstrated HIV-1 risk reduction in adult women older than 21 years but not in those aged 18-21 years. Lack of protection was correlated with low adherence.

METHODS

In this phase-IIa, randomized, double-blind, placebo-controlled, US, multicenter trial of the dapivirine ring in sexually active females, aged 15-17 years, participants were randomized 3:1 to a dapivirine or placebo ring to be inserted monthly for 6 months (NCT02028338). Primary safety end points included grade 2 product related adverse events and any grade 3 and higher adverse events. Adherence to ring use was assessed by plasma dapivirine concentrations, residual levels in used rings, and self-report. A plasma dapivirine concentration of >95 pg/mL was used to define short-term adherence; a residual ring level of <23.5 mg was used to define long-term adherence. Acceptability was assessed through computer-assisted self-interviews.

RESULTS

Ninety-six participants were enrolled across 6 US sites. The median age was 16.0 years. There were no differences in safety outcomes between treatment arms. Adherence to the dapivirine ring was demonstrated by both plasma measurements (87%) and residual drug levels in rings (95%). Forty-two percent (95% confidence interval: 32 to 52) of participants reported that they never removed the ring. Participants noted no discomfort due to the ring at 87% of visits and "liking" the ring at 93% of visits.

CONCLUSION

The dapivirine vaginal ring, a promising topical microbicide, was well tolerated and acceptable in young US adolescents.

Educating men about vaginal microbicides: considerations from Kenya

Men desire to be involved in their partner's decision-making about vaginal microbicide use. This coincides with women's desire to inform male partners about their microbicide use. Educating men about microbicides may enhance acceptability and generate critical support for the female participants of microbicide trials. In this multiphase mixed-methods study, we adapted an educational intervention on vaginal microbicides and tested it among men (n = 45) to determine its effect on men's knowledge regarding HIV/STI, vaginal microbicides and microbicide trials. We also conducted focus group discussions (FGDs) with the female partners (K = 3, n = 43) of the study participants and community representatives (K = 2, n = 24) to obtain their views on male partner microbicide education. We analysed FGD data for key themes using content analysis. HIV and vaginal microbicide knowledge scores increased significantly among men after the educational intervention. Both women and men highly supported male partner microbicide education, in the context of existing gender relations, to increase men's understanding about microbicides, promote adherence and help women gain their partners' trust. Complex gender dynamics should be considered when designing male partner educational interventions to improve acceptability and the use of microbicides and other female-initiated HIV prevention methods.

Impact of Male Partner Involvement on Women's Adherence to the Dapivirine Vaginal Ring During a Phase III HIV Prevention Trial

Although vaginal microbicides for HIV prevention are designed to be female-initiated, male partner influence has been identified as one of the most significant factors impacting women's willingness and ability to use them. As a result, research teams have sought to increase male partner involvement by encouraging disclosure of product use to male partners, promoting male partner engagement in the study through attendance at the study clinic, and helping women to garner male partner support for product use. This paper aims to assess the impact of these three elements of male partner involvement on women's adherence to the dapivirine vaginal ring during MTN-020/ASPIRE, a phase III randomized placebo-controlled clinical trial involving 2629 women in Malawi, South Africa, Uganda, and Zimbabwe. During the study, 64-80% of participants reported disclosure of ring use at each quarterly visit, and 13% reported that their partners had attended the study clinic at some point during the study. At study exit, 66% reported that their partner was supportive, 18% unsupportive, and 17% were unsure. After adjusting for age, site and time in study, women were more likely to have low ring adherence if they had an unsupportive male partner (aRR 1.29, 95% CI 1.03-1.62). Neither disclosure nor clinic attendance directly predicted ring adherence, but disclosure increased the probability of having a supportive partner (aRRR 24.17, 95% CI 16.38-35.66) or an unsupportive partner (aRRR 4.10, 95% CI 2.70-6.24), relative to an unknown level of partner support. Women were also more likely to have a supportive partner if their partner had attended the clinic (aRRR 3.77, 95% CI 1.36-10.42). This study suggests that although the vaginal ring is relatively discreet, lack of support from male partners remains a relevant barrier to use. Though both disclosure and clinic attendance may increase partner support, disclosure may also increase partner opposition. Interventions to reduce male partner opposition are needed to maximize the potential impact of the ring and other PrEP products for HIV prevention.

A mixed methods investigation of implementation barriers and facilitators to a daily mobile phone sexual risk assessment for young women in Soweto, South Africa

BACKGROUND

The HIV epidemiology in South Africa reveals stark age and gender disparities, with young women being the most vulnerable to HIV acquisition in 2017. Evaluation of HIV exposure is a challenge in HIV prevention research. Intermittent in-clinic interviewer-administered risk behaviour assessments are utilised but may be limited by social desirability and recall biases. We piloted a mobile phone application for daily self-report of sexual risk behaviour in fifty 18-25 year old women at risk of HIV infection enrolled in HIV Vaccine Trials Network 915 (HVTN 915) in Soweto, South Africa. Through a mixed-methods investigation, we explored barriers and facilitators to completing daily mobile phone surveys among HVTN 915 study participants and staff.

METHODS

We analysed quantitative data on barriers and facilitators to mobile phone study completion collected during the larger HVTN 915 study as well as two post-study focus group discussions (FGDs) with fifteen former participants with a median age of 24 years (IQR 23-25) and six individual in-depth interviews (IDIs) with HVTN 915 staff. FGDs and IDIs utilised semi-structured interview guides, were audio-recorded, transcribed verbatim and translated to English. After coding, thematic analysis was performed.

RESULTS

The main facilitator for daily mobile phone survey completion assessed across 336 follow-up visits for 49 participants was the daily short message system (SMS) reminders (93%, 312/336). Across 336 visits, 31/49 (63%) retained participants reported barriers to completion of daily mobile phone surveys: forgetting (20%, 12/49), being too busy (19%, 11/49) and the survey being an inconvenience (15%, 9/49). Five main themes were identified during the coding of IDIs and FGDs: (1) facilitators of mobile phone survey completion, such as daily SMS reminders and follow up calls for non-completers; (2) barriers to mobile phone survey completion, including partner, time-related and technical barriers; (3) power of incentives; (4) response bias in providing sensitive information, and (5) recommendations for future mobile phone based interventions.

CONCLUSION

Despite our enthusiasm to use innovation to optimise sexual risk assessments, technical and practical solutions are required to improve implementation. We recommend further engagement with participants to optimise this approach and to further understand social desirability bias and study incentives in sexual risk reporting.

"It Was Not My Aim to Sleep There": The Impact of Timing and Location of Sex on Adherence to Coitally-Dependent HIV Pre-exposure Prophylaxis

The FACTS 001 trial found that vaginal pre- and post-coital application of 1% tenofovir gel did not prevent HIV-1 infection amongst young South African women. The trial included a multi-faceted approach to adherence support and collected objective and self-reported adherence measures. Using qualitative data collected from a random sub-set of FACTS 001 participants (135 in-depth interviews at product discontinuation and 13 focus group discussions at dissemination of trial results), we explore the importance of 'place' and 'timing' in shaping acts of sexual intimacy and product adherence. Demographically, this qualitative sub-sample is similar to the trial cohort of predominantly young, unemployed women living with parents or other family members. Sexual intimacy was largely unpredictable and happened across multiple locations in which women had limited privacy, autonomy, or control over the timing of sex. This made adherence to the dosing strategy challenging. Findings may inform the development of future event-driven pre-exposure prophylaxis regimens or products.

FAME-04: A Phase 1 trial to assess the safety, acceptability, pharmacokinetics and pharmacodynamics of film and gel formulations of tenofovir

INTRODUCTION

Fast-dissolving vaginal film formulations release antiretroviral drugs directly into vaginal fluid and may be as efficient at drug delivery yet more acceptable to women than gels. In this Phase 1 vaginal film study, the safety, acceptability, pharmacokinetics and pharmacodynamics of two doses of tenofovir (TFV) film and TFV 1% gel were compared to corresponding placebo formulations.

METHODS

Seventy-eight healthy HIV negative women were randomized to self-insert daily vaginal film (10 mg TFV, 40 mg TFV or placebo) or 4 mL of vaginal gel (TFV 1% [40 mg] or placebo) for seven days. Grade 2 and higher adverse events (AEs) related to study product were compared across study arms using Fisher's exact test. Plasma TFV concentrations were measured before and 2 hours after last product use. Paired cervical and vaginal tissue biopsies obtained 2 hours after the last dose were measured to determine tenofovir diphosphate (TFV-DP) concentrations and exposed to HIV in an ex vivo challenge assay. Acceptability was assessed through questionnaire.

RESULTS

There was only one grade 2 or higher related AE, the primary endpoint; it occurred in the placebo gel arm. AEs occurred in 90% of participants; the majority (91%) were grade 1. AEs were similar across study arms. TFV concentrations in plasma and TFV-DP concentrations in cervical and vaginal tissues were comparable between 40 mg TFV film and the TFV gel groups. There was a significant relationship between reduced viral replication and TFV-DP concentrations in cervical tissues. Film users were less likely to report product leakage than gel users (66% vs. 100%, p < 0.001).

CONCLUSIONS

Films were safe and well tolerated. Furthermore, films delivered TFV to mucosal tissues at concentrations similar to gel and were sufficient to block HIV infection of genital tissue ex vivo.

Factors Supporting and Hindering Adherence to Rectal Microbicide Gel Use with Receptive Anal Intercourse in a Phase 2 Trial

Adherence to product use in biomedical HIV prevention trials is essential to success. In MTN-017, a Phase 2 rectal microbicide gel trial, participants discussed applicator-inserted gel use in the context of receptive anal intercourse (RAI) with adherence counselors. We analyzed counseling session data to identify barriers to and facilitators of gel use for 26 participants in the United States who used gel with RAI as their first of three study regimens. The most common barriers were finding the gel application process cumbersome, physical discomfort after applying gel, difficulty with BAT-24 dosage regimen, and negative effects of gel on sex. The most common facilitators were incorporating gel use into routines, using gel in anticipation of sex, carrying gel when going out, reminders received via short message service, and ease of gel use. These findings can inform product development and future adherence counseling interventions for rectal gel trials to improve adherence outcomes.

Attitudes and perceptions towards novel objective measures of ARV-based vaginal ring use: Results from a global stakeholder survey

Results of recent microbicide and pre-exposure prophylaxis clinical trials have shown adherence to be a significant challenge with new HIV prevention technologies. As the vaginal ring containing dapivirine moves into two open label follow-on studies (HOPE/MTN-025 and DREAM) and other antiretroviral-based and multi-purpose prevention technology ring products advance through the development pipeline, there is a need for more accurate and reliable measures of adherence to microbicide ring products. We previously conducted a comprehensive landscape analysis to identify new technologies that could be applied to adherence measurement of vaginal rings containing antiretrovirals. To explore attitudes and perceptions towards the approaches that we identified, we conducted a survey of stakeholders with experience and expertise in microbicide and HIV prevention clinical trials. From May to July 2015 an electronic survey was distributed via email to 894 stakeholders; a total of 206 eligible individuals responded to at least one question and were included in the data analysis. Survey respondents were presented with various objective measures and asked about their perceived acceptability to trial participants, feasibility of implementation by study staff, usefulness for measuring adherence and ethical concerns. Methods that require no additional input from the participant and require no modifications to the existing ring product (i.e., measurement of residual drug or excipient, or a vaginal analyte that enters the ring) were viewed as being more acceptable to trial participants and more feasible to implement in the field. Respondents saw value in using objective measures to provide real-time feedback on adherence. However, approaches that involve unannounced home visits for sample collection or spot checks of ring use, which could provide significant value to adherence feedback efforts, were met with skepticism. Additional research on the acceptability of these methods to potential trial participants and trial staff is recommended.

Social Context of Adherence in an Open-Label 1 % Tenofovir Gel Trial: Gender Dynamics and Disclosure in KwaZulu-Natal, South Africa

CAPRISA 008, an open-label extension study of tenofovir gel with coitally-related dosing, provided an opportunity to explore the relationship between product adherence and gender dynamics in a context where women knew they were receiving an active product with evidence of HIV prevention effectiveness. Interviews with 63 CAPRISA 008 participants and 13 male partners in KwaZulu-Natal, South Africa, highlighted that the process of negotiating gel use was determined in part by relationship dynamics including the duration of the relationship, the living situation, an evaluation of the relationship (e.g., partner intimacy and relationship expectations) and culturally-defined steps for formalizing the relationship. While disclosure facilitated adherence for many, others reported using the gel effectively with no disclosure, and in some situations disclosure was a barrier to adherence. Women should be supported in their choice about what to disclose and have opportunity to use this and similar products without their partners’ knowledge or acquiescence.

Planning for HIV preexposure prophylaxis introduction: lessons learned from contraception

PURPOSE OF REVIEW

We summarize key lessons learned from contraceptive development and introduction, and implications for preexposure prophylaxis (PrEP).

RECENT FINDINGS

New approaches to HIV prevention are urgently needed. PrEP is a new technology for HIV prevention. Uncertainty remains about its acceptance, use and potential to have an impact on the HIV epidemic. Despite imperfect use and implementation of programs, the use of modern contraception has led to significant reproductive health and social gains, making it one of the public health's major achievements. Guided by the WHO strategic approach to contraception introduction, we identified the following lessons for PrEP introduction from contraception: (1) the importance of a broader focus on the method mix rather than promotion of a single technology, (2) new technologies alone do not increase choice--service delivery systems and providers are equally important to success, and (3) that failure to account for user preferences and social context can undermine the potential of new methods to provide benefit.

SUMMARY

Taking a strategic approach to PrEP introduction that includes a broader focus on the technology/user interface, the method mix, delivery strategies, and the context in which methods are introduced will benefit HIV prevention programs, and will ensure greater success.

An interdisciplinary framework for measuring and supporting adherence in HIV prevention trials of ARV-based vaginal rings

INTRODUCTION

Product adherence and its measurement have emerged as a critical challenge in the evaluation of new HIV prevention technologies. Long-acting ARV-based vaginal rings may simplify use instructions and require less user behaviour, thereby facilitating adherence. One ARV-based ring is in efficacy trials and others, including multipurpose rings, are in the pipeline. Participant motivations, counselling support and measurement challenges during ring trials must still be addressed. In previous HIV prevention trials, this has been done largely using descriptive and post-hoc methods that are highly variable and minimally evaluated. We outline an interdisciplinary framework for systematically investigating promising strategies to support product uptake and adherence, and to measure adherence in the context of randomized, blinded clinical trials.

DISCUSSION

The interdisciplinary framework highlights the dual use of adherence measurement (i.e. to provide feedback during trial implementation and to inform interpretation of trial findings) and underscores the complex pathways that connect measurement, adherence support and enacted adherence behaviour. Three inter-related approaches are highlighted: 1) adherence support - sequential efforts to define motivators of study product adherence and to develop, test, refine and evaluate adherence support messages; 2) self-reported psychometric measures - creation of valid and generalizable measures based in easily administered scales that capture vaginal ring use with improved predictive ability at screening, baseline and follow-up that better engage participants in reporting adherence; and 3) more objective measurement of adherence - real-time adherence monitoring and cumulative measurement to correlate adherence with overall product effectiveness through innovative designs, models and prototypes using electronic and biometric technologies to detect ring insertion and/or removal or expulsion. Coordinating research along these three pathways will result in a comprehensive approach to product adherence within clinical trials.

CONCLUSIONS

Better measurement of adherence will not, by itself, ensure that future effectiveness trials will be able to address the most basic question: if the product is used per instructions, will it prevent HIV transmission? The challenges to adherence measurement must be addressed as one component of a more integrated system that has as its central focus adherence as a behaviour emerging from the social context of the user.