The little blue pill that can stop HIV: PROUD study enrolling gay men in the UK

Simon Collins, HIV i-Base

The PROUD study using tenofovir/FTC as PrEP to reduce the risk of HIV transmission enrolling well but may only have a limited window for new participants. Continued enrollment is essential in order to generate UK data to enable PrEP to become an option for men who continue to be at high risk.

This study offers gay men in the UK one of the few chances to be able to use PrEP and as such should receive a high profile in GUM clinics.

The iPrEX study reported the potential to reduce the risk of transmission by more than 95% with good adherence. Given the high levels of new HIV transmissions among gay men in the UK (3500 new diagnoses in 2012), this is a compelling opportunity to use a new approach.

This is a two year study and participants are randomised to either immediate PrEP or deferred access in the second year. This is a much better than using a placebo design (as in France), as all participants are guaranteed access to PrEP.

Although some people may be disappointed to be randomised to the delayed group, the study still provides PrEP long before the NHS is likely to decide on broader access. The study include good care, support and monitoring, but otherwise just involves keeping an adherence diary, plus potential sexual risks.

PrEP is likely to have the greatest protection for people who have the greatest risks. So it is not targeted at people who currently use condoms every time.

For people who don’t always use condoms, or don’t regularly use condoms, this study could prevent their next HIV test coming back positive. A recent survey reported that about 50% of gay men in London were interested in PrEP as an option to prevent HIV.

This largest study in gay men (iPrEX) was particularly important because it enrolled men who had a high risk of catching HIV.

This profile would broadly overlap with factors that are relevant to gay men in the UK who have a high risk for HIV.

  • Half were 18-25 and most of the rest were under 40.
  • Men were sexually active (average 18 partners in the previous 3 months).
  • Alcohol use was common (half had more than 4 drinks on days they were drinking).
  • Condom use was inconsistent (80% had had sex without a condom in the previous 6 months).
  • HIV was rarely discussed before sex (only 2% had knowingly had recently sex with a positive partner).
  • At least 10% ofmen had also had a recent STI.

The iPrEX study showed that PrEP had a greater protection against HIV than condoms, but this was dependent on good adherence.

This is because consistent condom use is low and they can tear or fall off. In the context of good adherence, the protection from PrEP is continuous – 24 hours a day, 7 days a week.

Protect is likely to be systematic and include against oral transmission.

Just as condoms sometimes get missed, pill can be forgotton. Luckily, the level of protection is still likely to be high with occasional missed dose. Unlike HIV treatment, missed doses for PrEP is not associated with a risk of developing drug resistance in HIV negative people.

The researchers caution that PrEP does not protect against other sexually transmitted infections (STIs) and the study emphasises the importance of condoms and includes other information to support better sexual health.

The PROUD study is being run at nine of the largest sexual health clinics in London. It is also running in Birmingham,Brighton, Manchester, Sheffield and York.

The study is sponsored by Public Health England (PHE) and the Medical Research Council (MRC).


i-Base supports this study as a potentially important and exciting option for gay men to be able to use if they are at a high risk of catching HIV.

i-Base has no financial relationship with the study or the clinic sites.

Further information and links:

Links to other websites are current at date of posting but not maintained.