On-Demand PrEP Is Great. Now, What About Women?

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In 2012, pre-exposure prophylaxis (PrEP) revolutionized biomedical HIV prevention. PrEP, an oral antiretroviral medication taken in concert with other risk reduction strategies, proved to all but eliminate one's risk for HIV acquisition. Nevertheless, we learned early on that PrEP uptake and efficacy were not equally beneficial among users. There has been much debate among researchers and community, alike, as to the timeframes required to achieve a level of PrEP protection against HIV. The Centers for Disease Control and Prevention (CDC) recommends that PrEP be taken for approximately 20 days to establish a systemic level of protection in vaginal tissues, while the World Health Organization (WHO) recommends seven days. However, for men who have sex with men (MSM), both the CDC and WHO recommend seven days of PrEP use to achieve protective levels against HIV in rectal tissues.

Results from the French IPERGAY study challenged the latter recommendation and showed that, in MSM, PrEP taken on demand -- that is in advance of and immediately preceding unprotected anal sex -- has the same level of protection against HIV as PrEP taken once daily. Show-stopping results from the most recent International AIDS Conference (AIDS 2018) further confirmed the efficacy of on-demand PrEP with observational data from the PREVENIR study. [[As reported by TheBodyPRO, among those who participated in the study, 99% of who were MSM, PrEP has shown a high level of effectiveness in preventing HIV when taken on demand.

For MSM, PrEP on demand is undoubtedly a game changer. However, this leads to several important questions: What about women? What do on-demand PrEP advances seen in men mean for a developing a biomedical prevention agenda for women? There is no indication for on-demand PrEP in women, nor is there research underway to explore the possibility. As such, the historic exclusion of women from receiving the same scientific benefits experienced by men will continue to persist if not grow larger.

"With the majority of PrEP studies conducted this far, the news is good, with clear and definitive evidence of effectiveness and efficacy of PrEP for gay men," said Dazon Dixon Diallo, M.P.H., executive director of SisterLove. "For women, in all our diversities, the outcomes are usually not as good, or at best, mixed, and less exciting."

A future research agenda of biomedical HIV prevention, especially among the most highly impacted women, must be multi-modal to include products such as gels and implants, and not limited to only oral formulations. It must also continue to assess women's social and sexual health circumstances and allow these circumstances drive product development.

When this fully embraced, women will be able to benefit from the use of vaginal rings that double as birth control and HIV prevention, but first there has to be a commitment to a robust research agenda for biomedical prevention options that work well for women, biologically and culturally. Stigmatizing language characterizing women as a "difficult-to-reach" population; a lack of global consensus on PrEP guidelines (CDC and WHO), particularly on timeframes required to level of vaginal protection or any true pharmacokinetic measurement of PrEP protection; and the lack of meaningful inclusion of women in sex-positive women-centered conversations and public health messaging efforts, will continue to limit women's uptake of PrEP.

"The uptake and sustainability of the drug in the body show that vaginas and rectums absorb the drug very differently," said Dixon Diallo. "This tells us that all things are not yet equal regarding the protection that PrEP offers, and that we still have a long way to go to find the most effective and appropriate ways that PrEP can work just as well, flexibly, and efficiently, in women as it does for men."

I remind you on behalf of women, we must do better.

Danielle M. Campbell, M.P.H., is a sexual health research advocate from Los Angeles. She is chair of the Los Angeles Women's HIV/AIDS Task Force.