LifeGuide [Destination: Cure]
It’s a Man’s World
Research on women & PrEP needs to keep pace
by Jeannie Wraight
Whereas HIV cure and HIV prevention are two very different topics, I think it’s important to discuss the recent developments from the VOICE trial (women’s PrEP and microbicides study). With all the talk about PrEP, it’s essential to distinguish the research results of PrEP for men and PrEP for women, as they differ dramatically.
The VOICE (Vaginal and Oral Interventions to Control the Epidemic) Study was a large clinical trial conducted at four sites in Zimbabwe, South Africa (two), and Uganda. The study consisted of 5,029 women who were randomized in one of five groups:
• Oral Truvada PrEP
• Oral tenofovir PrEP
• Oral placebo
• Tenofovir vaginal microbicide gel
• Placebo vaginal gel
The average age of the women on the trial was twenty-five. The majority (seventy-nine percent) were single.
The study took place from September 2009 to August 2012. In September 2011, the Truvada oral PrEP arm was discontinued and, in November 2011, the Tenofovir vaginal microbicide gel and placebo arms were halted due to “futility.” Basically no benefit was seen in either Truvada PrEP or the microbicide gel. The tenofovir oral PrEP and placebo arms continued until their designated end dates, but tenofovir oral PrEP also showed no benefit over placebo. There were 312 (5.7 percent) new HIV infections among all trial participants.
These results were likely based on a lack of adherence to the prevention methods. This, despite a ninety percent adherence rate reported by study participant answers on the self-reported study questionnaire and investigator pill and gel tube counts, as well as a low drop-out rate (nine percent).
Further data will be presented at the 2015 Conference on Retrovirus and Opportunistic Infections that took place in Seattle, Washington on February 23 to the 25 (after this article went to print).
Results of clinical trials of PrEP in women have had varying rates of success and failure. Results of the FEM-PrEP study were similar to the VOICE study findings in that the women in both studies simply did not utilize the study interventions. Like the VOICE study, FEM-PrEP was discontinued, as investigators found no benefit to Truvada PrEP over placebo based on non- adherence.
In contrast, two large studies of Truvada in heterosexual couples, Partners PrEP and TDF2 demonstrated a seventy-five percent and sixty-two percent protection rate, respectively.
What is needed now to determine if PrEP holds any validity for women is a trial similar to the IPERGAY PrEP study, which was based in France with men who have sex with men (MSM). The trial, which began in February 2012, was halted early because it demonstrated, without doubt, that PrEP was effective as a preventative measure in this study. The interesting thing about IPERGAY was that the study determined that intermediate use of PrEP was effective in conferring protection against HIV. In other words, you didn’t have to take Truvada every day in order to prevent HIV. Two doses of Truvada PrEP were taken within twenty-four hours of an anticipated act of unprotected sex. If intercourse did occur, the participants then took one pill a day for the following two days. Data on the full results of IPERGAY have not yet been released and are expected this year.
The IPERGAY study involved 400 MSMs and zero women. Intermediate PrEP is yet to be studied in women. A study such as IPERGAY for women is extremely important in determining whether PrEP is at all useful to women in general in real-world situations.
Discussions on PrEP and the language used to educate potential users MUST begin to differentiate between PrEP in MSMs, which for whom clear benefit exists, and women for whom it does not. At this point, it is still not clear whether PrEP for women is effective. All of the studies with women were based in African countries. Adherence was a major issue in both VOICE and FemPrEP. In the VOICE study, no study drug was detected at any point in many of the women when blood tests were employed. If PrEP studies in women in the U.S., Europe, and Asia produce the same effects and we find intermediate use is not enough, where do we go from there?
If it’s proven that intermediate use of oral PrEP in women in fact does not induce protection from HIV, future versions of PrEP may still hold benefit. Researchers are working on long-lasting injections and a thirty-day vaginal microbicide ring that would take poor adherence out of the equation and provide women with a long-lasting method of protection against HIV. These options, if shown to be efficacious, are several years away, however.
Jeannie Wraight is the former editor-in-chief and co-founder of HIV and HCV Haven (www.hivhaven.com) and a blogger and writer for TheBody. com. She is a member of the Board of Directors of Health People, a community-based organization in the South Bronx and an advisor to TRW (Teach me to Read and Write), a community-based organization in Kampala, Uganda. She lives with her husband in New York City.