Study Results, Key Messages, Questions and Answers

PROUD Results Key Messages and Q&A

PROUD Study Key Messages, Q&A and further HIV PrEP trial information

Study Results

24 February 2015

The PROUD study today reported that PrEP reduced the risk of HIV infection by 86% for gay and other men who have sex with men when delivered in sexual health clinics in England.

The PROUD study measured the effectiveness of daily PrEP for gay and other men who have sex with men in England.  The results released at the Conference on Retroviruses and Opportunistic Infections today indicate that PrEP is highly protective for this group, reducing the risk of infection by 86%. The researchers concluded that PrEP offers a major opportunity to curb new HIV infections in men who have sex with men in the UK.

The drug used in the trial – the antiretroviral Truvada (usually used to treat HIV) – was already known to reduce the incidence of HIV infection in placebo controlled trials.  The PROUD study was designed to see if the same effect would be found in a real world situation where participants knew they were taking an active drug.  It aimed to address outstanding questions such as whether taking PrEP would change sexual risk behaviour – for example increasing the number of partners they did not use condoms with and increasing the rate of other sexually transmitted infections (STIs) – and whether or not it would be cost-effective to make it available on the NHS. 

The study was launched in 2012, enrolling 545 participants at 13 sexual health clinics in England. The study enrolled gay and other men who have sex with men, who reported having had anal sex without a condom in the previous 3 months and were likely to do so the same again in the near future. The study randomised participants to receive PrEP immediately or to receive PrEP after a period of 12 months, allowing researchers to compare those on PrEP versus those not yet on PrEP. 

In the study there were 1.3 new infections per 100 person-years in the group given PrEP immediately, and 8.9 per 100 person-years in the group who were not yet on PrEP. The 86% protection from daily PrEP reported by the study is the highest reported from any randomised controlled trial of PrEP to date.

The sexual health clinics that took part in the PROUD study were able to adapt their routine practice to include PrEP. Participants incorporated PrEP into existing risk reduction strategies, which included condom use.  There was no difference in the number of men diagnosed with other STIs between those on PrEP and those not on PrEP.

Sheena McCormack, Professor of Clinical Epidemiology at the MRC Clinical Trials Unit at UCL, and Chief Investigator of the PROUD study, said: "These results are extremely exciting and show PrEP is highly effective at preventing HIV infection in the real world. Concerns that PrEP would not work so well in the real world were unfounded. These results show there is a need for PrEP, and offer hope of reversing the epidemic among men who have sex with men in this country. The findings we've presented today are going to be invaluable in informing discussions about making PrEP available through the NHS."

Stefan Laros, a participant in the PROUD study, said: "I am immensely pleased and overwhelmed - a little emotional even - as for the first time in 30 years I feel there is hope for people like me, who struggle with consistent condom use, but who want to protect themselves - and just as importantly - their sex partners against HIV infection."

Justin Harbottle, a programme officer at THT and a member of the PROUD Community Engagement Group who serve an advisory role to the study, said: "While the public health benefits of PrEP remain key, the personal benefits in providing people with a tool which can empower them to protect themselves from HIV, reduce anxiety and subsequently increase their sexual wellbeing, cannot be overstated enough. The task now remains to ensure that PrEP is made available as quickly as possible to those who most need it."

We want to thank the study participants, study staff and members of the various advisory committees (CEG, TSC, IDMC) for helping to make this study a resounding success!