Revolutionary new anti-HIV pill shown to work when taken 'on demand'

Pre-exposure prophylaxis (PrEP) drugs found to reduce infection risk when taken during sex

A pill which can reduce the risk of HIV infection by up to 90 per cent is most effective when used at the same time as sex, French researchers have said.

Trials of pre-exposure prophylaxis (PrEP) among gay men in the UK were extended earlier this month after the daily pills were shown to provide unprecedented protection to those most at risk of infection.

Now, in what researchers called a “major breakthrough in the fight against HIV” a separate French trial of PrEP has found that it also led to “a very significant reduction” in the risk of infection amongst men who took it while they had sex.

HIV charities are now urging the NHS to urgently consider introducing PrEP, which is already available to many gay men in the USA.

If the pill is taken on an on-demand basis, rather than daily, it could come at a significantly lower cost to the health service.

Yusef Azad, director of policy and campaigns at the National AIDS Trust, said that the results of the trial, conducted by ANRS, was “another exciting piece of news” adding to a “growing and powerful evidence base on the effectiveness of PrEP”.

“It is especially important if it suggests that PrEP might work well when taken only around the time of sex rather than daily. That could be good news for costs,” he said. “We will now need to look at how such 'intermittent PrEP' works in a real-life setting rather than a placebo-controlled trial.  

“This adds to the urgency of the NHS deciding how to introduce PrEP effectively to reduce the current record numbers of gay and bisexual men, and others at high risk, being diagnosed with HIV in the UK.”

Researchers involved in the UK’s PROUD trial gave PrEP pill Truvada to more than 400 men. A further 138 men who had been waiting to commence their course were invited to start taking the pills early, after initial review of the data showed impressive results.

The French trial, which recruited 400 men, also used Truvada. Professor Jean-François Delfraissy, director of ANRS, hailed the findings.

“This is a major breakthrough in the fight against HIV,” he said. “The results should change national and international recommendations towards HIV prevention.”

Nearly 100,000 people are living with HIV in the UK. Sex without a condom is the most common means of infection. Nearly half of all new infections are among men who have sex with men.