A novel breath test to directly measure use of vaginal gel and condoms

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.

Biomarkers and biometric measures of adherence to use of ARV-based vaginal rings

Introduction

Poor adherence to product use has been observed in recent trials of antiretroviral (ARV)-based oral and vaginal gel HIV prevention products, resulting in an inability to determine product efficacy. The delivery of microbicides through vaginal rings is widely perceived as a way to achieve better adherence but vaginal rings do not eliminate the adherence challenges exhibited in clinical trials. Improved objective measures of adherence are needed as new ARV-based vaginal ring products enter the clinical trial stage.

Methods

To identify technologies that have potential future application for vaginal ring adherence measurement, a comprehensive literature search was conducted that covered a number of biomedical and public health databases, including PubMed, Embase, POPLINE and the Web of Science. Published patents and patent applications were also searched. Technical experts were also consulted to gather more information and help evaluate identified technologies. Approaches were evaluated as to feasibility of development and clinical trial implementation, cost and technical strength.

Results

Numerous approaches were identified through our landscape analysis and classified as either point measures or cumulative measures of vaginal ring adherence. Point measurements are those that give a measure of adherence at a particular point in time. Cumulative measures attempt to measure ring adherence over a period of time.

Discussion

Approaches that require modifications to an existing ring product are at a significant disadvantage, as this will likely introduce additional regulatory barriers to the development process and increase manufacturing costs. From the point of view of clinical trial implementation, desirable attributes would be high acceptance by trial participants, and little or no additional time or training requirements on the part of participants or clinic staff. We have identified four promising approaches as being high priority for further development based on the following measurements: intracellular drug levels, drug levels in hair, the accumulation of a vaginal analyte that diffuses into the ring, and the depletion of an intrinsic ring constituent.

Conclusions

While some approaches show significant promise over others, it is recommended that a strategy of using complementary biometric and behavioural approaches be adopted to best understand participants’ adherence to ARV-based ring products in clinical trials.

'HIV has a woman's face': vaginal microbicides and a case of ambiguous failure

The case is a primary unit of knowledge production in the field of HIV research, yet the work that is done to construct cases often goes unremarked. In this paper, the case takes centre stage in an analysis of a set of apparent failures in HIV prevention research, namely a series of clinical trials to test vaginal microbicides. Returning to the genesis of the microbicide concept in the early 1990s, I examine how the discourse of women's empowerment was linked to HIV prevention in a way that mobilized a particular vision of the case, which was both politically and scientifically expedient. Drawing on an in-depth empirical study of one particular trial, I show the success of the case in mobilizing funds and interest in the research, as well its success in accounting for the failure of the pharmaceutical technology. Drawing in alternative scientific accounts of the failure of microbicides, however, a different version of events is indicated, in which what can ultimately be said to have failed is not the technology itself, but the act of casing upon which its testing was founded.

Microbicides and their potential as a catalyst for multipurpose sexual and reproductive health technologies

There is an urgent need for technologies to prevent sexual acquisition of HIV infection in young women in sub-Saharan Africa. After two decades of 11 pivotal trials of seven products, anti-retroviral-based topical microbicides are showing promise. Building on the CAPRISA 004 trial findings, several trials of new anti-viral agents, novel delivery mechanisms and combination/multipurpose products that address challenges of adherence and meet the sexual and reproductive health needs of men and women, including preventing HIV infection, are underway.