A proposed UK study of gay and bisexual men would look at the efficacy of giving them a daily oral HIV prevention pill.

The pilot study, which is still at an early stage, would give at-risk men a daily dose of Truvada, which has been found to lower the rate of new HIV infections.

It would be part of a larger HIV prevention initiative for gay and bisexual men, aidsmap.com reports.

The proposals, drafted by members of the British HIV Association (BHIVA) and the Health Protection Agency (HPA), were announced at the 17th BHIVA Conference in Bournemouth earlier this month.

Last year, a trial of almost 2,500 gay men around the world found an estimated 43.8 per cent reduction of new HIV infections among those who took Truvada daily to prevent HIV, compared to those who took a placebo pill.

Researchers want to see if the results of the study can be replicated.

The technique, known as Pre-Exposure Prophylaxis (PrEP), uses antiretroviral drugs with an aim to prevent HIV infection from occurring.

It remains in the experimental stage and there is concern that it may encourage risky behaviour, although a 2010 study of 400 gay men found no evidence for this.

Dr Tony Nardone, the HPA’s specialist in virology, told the Bournemouth conference between 3,600 and 6,000 “high risk” gay men could take part in the study, with half of these being given PrEP.

Professor Noel Gill, chief epidemiologist of the HPA, said that high risk gay men would be defined as those who attend a GUM clinic with a sexually-transmitted disease and have had unprotected anal sex in the last six months.

He said that funding for the two-year pilot programme had not yet been secured and would require input from a variety of sources, including health authorities and pharmaceutical companies.

BHIVA and the British Association for Sexual Health and HIV are to write a Position Statement on PrEP for publication in October.

The proposals were welcomed by HIV prevention charities.

Jason Warriner, clinical director for Terrence Higgins Trust, said: “This is a good move forward. We are now starting to understand how PrEP might work to protect gay men at an increased risk of HIV. However, it’s still early days. More rigorous research is needed in the UK before we know how feasible this approach is in the long-term.

“Whatever the outcome of this research, PrEP is just one part of the equation. Young gay men need better sex and relationships education in schools, and we need a continued focus on condom use and testing programmes to give gay men all the tools they need to stay safe.”

Deborah Jack, chief executive of National AIDS Trust said: “The annual number of new HIV diagnoses amongst gay men has increased significantly in the last decade and it is really important that we have as many tools as possible to prevent HIV transmission.

“PrEP could be an exciting new prevention option but research is still in the early stages. Having a pilot will help us understand if this might be an effective prevention tool in the UK and what the challenges around implementation may be.”