Questions and answers on Pre-exposure Prophylaxis for men who have sex with men

2 December 2014

Q: Why does WHO recommend that men who have sex with men consider taking antiretroviral medicines as an additional method to prevent HIV infection?

Rates of HIV infection are disproportionately high among men who have sex with men (MSM) in all regions of the world. This group is 19 times more likely to be living with HIV than the general population. It is estimated that the use of Pre-Exposure Prophylaxis (PrEP) globally could reduce HIV incidence amongst MSM by 20-25%, averting up to 1 million new infections over 10 years.

Q: Is WHO recommending that all MSM take antiretroviral drugs as a PrEP?

No, WHO does not recommend that all MSM should take PrEP. The recommendation, included in the Consolidated guidelines on HIV prevention, diagnosis, treatment and care for key populations, is that antiretroviral medicines should be offered as an additional prevention option, together with the use of condoms and other HIV prevention measures. In the same way that women are offered a range of different contraception options to choose from, WHO supports offering MSM the full range of HIV prevention options to suit their specific circumstances. In addition, a man may choose to use PrEP for only a specific period of his life when he feels at a higher risk of infection.

Q: Is PrEP always effective in preventing HIV infection?

Clinical trials to-date have shown that, when PrEP is taken properly and the drug regimen is fully adhered to, it can provide nearly complete protection from HIV infection. However, when the drugs are not taken as directed on a daily basis, success results may be significantly lower. The challenge of consistent use and adherence is not unique to PrEP, but applies to any HIV prevention method, including condoms.

Q: How do you know that MSM will be interested in this prevention option?

There is strong evidence of support among many MSM to have PrEP available as an additional prevention option. Across reviewed studies, between 40% and 70% of respondents reported an interest in and willingness to use PrEP. Although awareness of this prevention option is still limited globally, it is increasing as more clinical trials and pilot implementation programme results become available.

Q: If PrEP is so effective and men who have sex with men are open to its use, why not just recommend it for all MSM?

PrEP is recommended as an additional prevention choice for all MSM. But this does not mean that all MSM will choose to take it. The decision to use PrEP should be an individual one, based on needs, preferences, sexual behaviour, experience with other prevention options, and environment. It should always follow a discussion with a specialized health worker. It is also vital to remember that there are still many barriers and constraints to providing HIV services to MSM. Stigma, criminalization and human rights abuses deter many men from being tested or accessing prevention options. The WHO Consolidated guidelines on HIV prevention, diagnosis, treatment and care for key populations aim to tackle these inequities and injustices not only for MSM, but for all the key populations where HIV incidence remains high or is increasing.

Q: Do men who use PrEP as a prevention option still need to take other precautions against HIV infection?

Yes, PrEP is an additional HIV prevention choice for MSM, and WHO recommends that it is used together with condoms, which will also protect against other sexually transmitted diseases (STIs). PrEP does not protect against other STIs.

Q: What are the health implications for a healthy, HIV-negative man taking PrEP?

The drug that is currently used for PrEP has already been extensively used for the treatment of HIV infection. Its safety profile is well documented and it is considered a safe drug to use. All drugs, however, can have some side effects, even if these are minor or rare, and this also applies to the drug used for PrEP. As such, PrEP should be provided in a clinical setting where its safety can be monitored and where, should a problem occur, corrective action can be taken.

Q: What about other people? Why is WHO not recommending PrEP for other populations?

The WHO does recommend the use of PrEP for other populations, namely for serodiscordant couples, whether the HIV-negative partner taking PrEP is a man or a woman. However, these recommendations were limited to the context of demonstration projects when they were released in 2012. Less evidence was available then, both in terms of clinical trials, implementation studies, and in terms of values and preferences of the different populations affected. WHO will be reviewing the mounting evidence over the next few months and update its recommendations as deemed appropriate.

Q: Two recent PrEP MSM trial have been stopped early. What does this mean?

Two trials, one with daily PrEP (PROUD) and one with intermittent, event-linked PrEP (IPERGAY) have been stopped. The full data from these studies are still being checked and final results cannot yet be presented. However, initial analyses already confirm that both studies will show PrEP to be of significant benefit. All participants in the studies are now being offered PrEP and will no longer be monitored to assess its efficacy but rather to assess their continued adherence to the intervention and their ongoing acceptance of PrEP.

Until data from these two studies can be examined in depth, it is not possible for WHO to change its existing PrEP recommendations or to make new ones. However, these latest studies highlight the growing strength of evidence for PrEP use by high risk MSM and provides further justification for WHO’s recent recommendation.