Microbicide acceptability research: recent findings and evolution across phases of product development

PURPOSE OF REVIEW: Research on the acceptability of microbicides has the potential to inform the microbicide development process by shedding light on desirable product characteristics, issues around product use and potential barriers. The purpose of this review is both to synthesize recent findings that are related to microbicide acceptability, highlight areas of deficiencies, and to point to the new directions in which research is needed. RECENT FINDINGS: Recent studies have assessed acceptability using candidate microbicides in clinical trials, surrogate products, and descriptions of hypothetical products. While most studies have focused on physical characteristics of products, some small studies have investigated participants' short-term experiences with products during sexual intercourse. Overall, as currently measured and in their present formulations, vaginal microbicides have been found to be acceptable to adolescent girls, women, heterosexual men, whereas rectal microbicides were acceptable to men who have sex with men. Few studies have examined acceptability among high-risk HIV-uninfected women. The relationship between acceptability and adherence in trials, and ultimately in real-world settings, remains unknown. SUMMARY: Data are needed on acceptability of microbicides from larger populations, high-risk HIV-uninfected women, as well as long-term acceptability and contextual factors surrounding acceptability. The association between acceptability and long-term adherence in clinical trials or ultimately in the open market has yet to be demonstrated.