BREAKING: Second case of HIV infection on PrEP

This article originally appeared in BetaBlog.

At the HIV Research for Prevention conference in Chicago today, the HIV community received news of the second well-documented PrEP failure case. Howard Grossman, from Cleveland Clinic in Florida, shared information about a male client on Truvada PrEP since January 1, 2016 who seroconverted. Here’s what we know about what happened.

The man on PrEP who seroconverted was a man in his 20s who has sex with other men. He was in a relationship with a man who has been living with HIV since 2012 and who has maintained an undetectable viral load.

The man on PrEP did not acquire HIV from his primary male partner. This was confirmed by genetic comparisons of the strain of HIV acquired by the man on PrEP and the strain of the partner, which revealed they were “unrelated viral populations.”

The man on PrEP had two other sex partners on two separate occasions 5.5 and 11 weeks before testing positive for HIV. Both times, the man on PrEP was the “top,” or insertive sex partner. Grossman concluded that the man’s history was “consistent with transmission during condomless insertive anal intercourse.”

The man on PrEP was adherent to PrEP. “Excellent adherence” was confirmed by measures of tenofovir in blood spots and hair taken from the client.

This case is the second well-documented case of HIV infection with adherence to PrEP. The first, also from a man who acquired multi-drug resistant HIV, was presented in early 2016 at the Conference on Retroviruses and Opportunistic Infections. (Read more from PrEP researchers Robert Grant, MD, MPH on his interpretation of the first PrEP failure case.)

For more information, read the Q&A by Damon Jacobs with Dr. Howard Grossman on The Body.