CROI 2015: PrEP, microbicide findings show divergent paths of prevention responses

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Science Speaks is covering the 2015 Conference on Retroviruses and Opportunistic Infections in Seattle Washington live this week, from February 23-26, with breaking news on HIV research findings and implications.

Science Speaks is covering the 2015 Conference on Retroviruses and Opportunistic Infections in Seattle Washington live this week, from February 23-26, with breaking news on HIV research findings and implications.

Results of PROUD, Ipergay studies among European and Canadian men further talk of maximizing use, while FACTS 001 findings underscore failures to find an HIV protection measure African women can use

SEATTLE, WA — Presentations on two studies this morning highlighted the promise of antiretroviral drugs as pre-exposure prophylaxis against acquiring HIV (commonly known as PrEP), giving numbers to findings already known to be good news. Answering questions not only on effectiveness, but on uptake, adherence, safety, and risks (the use of PrEP does not appear to increase people’s willingness to take risks) all with positive findings, the PROUD and Ipergay studies produced results that became part of ongoing discussions that today began with a plenary talk on not if, but how, to make the most of a proven prevention measure.

In the same morning session of prevention presentations, the findings from a third much anticipated trial served up a fresh helping of bad news in ongoing efforts to find an HIV prevention measure that women can control, in Africa, where the challenges to doing that are substantial. The results from FACTS 001, a nine-site trial in South Africa, had been hoped to replicate favorable findings from the smaller scale CAPRISA trial that showed an antiretroviral vaginal gel for women could confer Reesa modest HIV prevention benefit. Instead, in results presented this morning, FACTS 001 showed, with the same rates of HIV infection among women assigned the product and a placebo in a randomized trial, that women could not use the product adequately for it to be effective. Those findings are, it appeared, the last nail in the coffin for one approach to a strategy that once seemed a simple answer to putting protection into the hands of those who need it most. “We can’t get away from the fact that used like this it didn’t work,” Helen Rees, protocol chair for the trial, who made the presentation of its findings said.

Following the VOICE trial of Vaginal and Oral Interventions to Control the Epidemic among women in Africa, and alongside the advances demonstrated by the PROUD and Ipergay trials, the findings reiterated a disconnect between the development of products for young women among whom rates of HIV are highest, and the lives of the young women themselves.

All three trials highlighted need.

McCormackPROUD (Pragmatic Open-Label Randomised Trial of Pre-Exposure Prophylaxis) was designed to show uptake and retention to a PrEP program such as that shown to reduce HIV acquisition in the iPrEx study, but “in the real world” with one group delaying enrollment in a PrEP program for a year, and another starting immediately. It showed making PrEP available immediately to be effective, and important. Of the group that deferred starting PrEP, 19 men, or 8.9 percent of the group, became infected with HIV during the trial. Of the group that started immediately, three men became infected with HIV. One likely was already infected and sero-converted as the trial started,and the other two had stopped taking the drug for months before they became infected, Sheena McCormack, the study’s chief investigator, who presented the results said. HIV incidence among those not taking antiretroviral drugs to prevent acquiring the virus were higher than expected, McCormack said. The success of antiretroviral drugs in preventing infection in PROUD was so expected that McCormack was asked if investigators faced challenges from an ethics board for having a deferred PrEP group.

MolinaIpergay was intended to address issues of adherence, as well as cost and potential side effects of daily antiretroviral drugs taken as PrEP. Taken before and after sex, it offered an “on-demand” approach, that added up to fewer pills taken over the course of a month, but equal protection. On October 23, a data monitoring board recommended that the placebo arm be discontinued, and everyone offered the real thing. The study’s coordinator Jean-Michel Molina pointed to the advantage of “on demand” PrEP: “The strategy is in the hands of the people.”

Putting an effective HIV prevention strategy into the hands of women will mean a search for products that fit into the lives of the women who need them, said Rees, who emphasized that evidence showed that 87 percent of the women used the product at least some of the time. “Most of the women tried to use it 50 percent to 60 percent of the time. But that clearly wasn’t enough,” she said. “Twenty-two percent of the women had [the product] in all samples. Eighty-seven percent of the women tried to use this product. They tried. But they couldn’t.”

The product tested in the trial requires a high level of use to be effective, Rees noted. “You have to be right up there in adherence.” The women in the trial were exceptionally young, with about 70 percent of the enrollees under 25, many still living with their parents or siblings, and unmarried, circumstances that challenged having a product on hand before sex — which would occur outside their homes.

“We have to get our heads around the lives of these women,” she said.

“We’ve had wonderful breakthroughs for men in the north,” she said. “We really have to do something for women in Africa.”

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