Not a single gay man who took two HIV prevention pills before and after sex had contracted HIV within a year thereafter, new research has found.
The results of the Prevenir study, which was conducted among about 1 500 men in Paris between May last year and this year, were released at the 22nd International Aids conference in Amsterdam on Tuesday.
Pre-exposure prophylaxis, or PrEP, in the form of a tablet that consists of two antiretroviral drugs — tenofovir and emtricitabine — is an HIV prevention strategy supported by the Joint United Nations Programme on HIV and Aids. One of the UN’s five prevention targets is to reach 3-million people worldwide with PrEP by 2020.
Several studies over the past eight years have shown that taking the pill can drastically reduce someone’s chances of contracting HIV through sex —by up to 96%, if PrEP is taken daily.
Once there is a high enough level of those two medications in an HIV-negative person’s vaginal or anal tissues, the drugs are able to, most of the time, shield the immune system cells from being infected by HIV when exposed to the virus.
LISTEN: Prep user talks sex, condoms and HIV
South Africa approved the use of PrEP in 2015 — it is available in the private health sector at a monthly cost of about R250 and the health department provides it for free at demonstration sites to high risk groups such as sex workers, men who have sex with men and young women.
Current PrEP guidelines require women who have receptive vaginal sex, to take the pill daily for about a month, before using it as an HIV protection method. For anal sex, research has shown, the medication has to be taken once a day for about a week to shield against HIV infection.
The shorter period needed to reduce the chances of HIV infection during anal sex relates to the ingredients of PrEP tending to concentrate in the rectum. A 2015 study published in the Journal of Infectious Diseases showed that 10 times more of the pill is retained in the rectum than in the vagina.
One of the challenges with daily PrEP, however, is getting users to take it consistently — the less often it is taken, the less protection it provides.
WATCH: How to prevent HIV with a pill
The Prevenir study divided research participants in two groups: about half of the study subjects received daily PrEP and the other half on-demand PrEP, which is higher dosages of the drug, but it’s taken only before and after sex.
“The on-demand users took the same pill, but they had to take two of the pills at least two hours before sex and then another two pills after sex,” lead researcher Jean-Michel Molina, from the infectious disease department at the Saint-Louis Hospital in Paris, explains. “One pill has to be taken within 24 hours after sex and another within 48 hours.”
The study found that daily and on-demand PrEP were equally effective — not a single participant contracted HIV, although members of both groups displayed risky sexual behaviour. For instance, when they were interviewed before being enrolled in the study, the men reported that they had an average of between ten and fifteen sexual partners in the prior three months and between two and three condomless sex acts in the month before enrolling.
The new results mean there is now another prevention option available for men who have sex with men when they engage in risky sex — also for men who have sex with men in South Africa. “But it’s important to remember to take the pills both before and after sex,” says Molina. “After you’ve taken these dosages, you are good, you don’t have to worry about HIV.”
LISTEN: Mitchell Warren, the executive director of the global HIV advocacy organisation, Avac, talks about what new PrEP findings mean for South Africa
But, warns, Mitchell Warren from the international HIV advocacy organisation, Avac, there is no evidence that on-demand PrEP will work as well for women. “We know from all of the clinical trials that studied daily PrEP, that the pill is less forgiving in women than men — it’s a biological reality.
“If you are a gay man, and risk exposure to HIV through anal intercourse, on-demand PrEP can work for you and that’s a very personal decision. But for women, the message still needs to be: daily oral PrEP, taken consistently, is safe for women.”
PrEP uptake has been slow in South Africa’s public sector. Health department data shows that between June 2016 and May, the pill was offered to 32 537 HIV-negative sex workers, but only 4109 (13%) took up the offer.
Among men who have sex with men the uptake was, however, significantly higher: of the 2857 men who were presented with PrEP between April 2017 and March, 1 537 (54%) started to take it.
“We have not shown that we’re getting the message across to potential users about how PrEP can be used,” the health department’s deputy director general for HIV, Yogan Pillay, explains. “It’s also quite difficult to use because it depends on one’s sexual behaviour, and people are not engaging in risky sexual behaviour all the time. So they feel they only need to take it when they are performing sexual acts that are risky.
But you have to take PrEP every day for the period that you’re engaging in risky sexual behaviour.”
LISTEN: The national health department’s deputy director general for HIV Yogan Pillay explains the PrEP challenges South Africa faces
South Africa’s national HIV plan aims to have provided just over 104 000 new users from high-risk groups with PrEP by 2022.
Pillay says “we don’t know what the market is for on-demand Prep in SA”. “But if you look at the morning-after-pill [that is also available on-demand], for which there is a significant market, you can gauge that there might be a market.”
While there’s not yet evidence that on-demand PrEP would work for young women, says Linda-Gail Bekker, the deputy director of the Desmond Tutu HIV Foundation, it’s “crucial” that we reach them with the daily HIV prevention pill. Bekker is also co-chair of the International Aids conference in Amsterdam.
Girls and women between the ages of 15 and 24 in South Africa are getting infected at rates up to eight times that of their peers, studies have found.
The health department started to provide PrEP at university clinics to young women in October. But, between then and May, only 6% of those to whom the pill was made available, took it. In May, the department began targeting adolescent girls at youth clinics, where the uptake seems to be significantly higher.
Bekker warns: “To be honest, young women really is what is at the heart of our epidemic [in Africa] so to withhold from them a tool that we know around the world is making a difference in reducing incidence [new infections] makes no sense to me.”