Men on effective HIV treatment, where the virus is reduced to undetectable levels are sexually non-infectious, finds an eight-year study led by UCL and the University of Copenhagen.
The preliminary findings of the PARTNER2 study will be presented at the 2018 AIDS conference in Amsterdam tomorrow. The study, which is the largest to look at the risk of HIV transmission when one partner is positive and on effective anti-retroviral treatment (ART) finds that having an undetectable viral load is as protective for gay men as it is for heterosexual couples.
“The PARTNER2 study was designed to find whether HIV transmission occurs in gay men when viral load was suppressed. Despite these couples having sex without condoms 75,000 times we did not find a single case,” said lead author, Dr Alison Rodger (UCL Institute for Global Health). Read more via UCL
excerpt from Heather Boerner's coverage of the conference for Medscape:
AIDS2018: Undetectable HIV Is Untransmittable and the 'Risk Is Zero'
"How Do You Know Someone Hasn't Become Detectable?"
The findings were met with general praise, but there were some questions for Rodger.
Some members of the audience asked how many people used drugs. The answer was very few and, even if they did, there were no transmissions with suppressed viral loads.
Others wanted to know the transmission rate for people with viral loads between 200 and 1000 copies/mL. Those data will be forthcoming at future conferences, Rodger reported.
Cohen asked how many of the HIV-positive men were newly virally suppressed. We're worried about the window between treatment initiation and 6 months of suppressed viral loads, "where we occasionally see transmissions," he explained.
PARTNER2 did have some participants who had been on suppressive therapy for only a few months, Rodger noted, "but we didn't include their data in the study if they weren't virally suppressed." When they were, they did not transmit the virus.
"How do you know that somebody hasn't become detectable? And how frequently do you think viral load testing is needed for monitoring people as undetectable?" asked one woman, who explained that "a lot of the resistance among clinicians to change their recommendations" is related to these questions.