The need for PrEP to be used in conjunction with condoms was highlighted this Tuesday (October 18) when scientists announced that a second man taking the daily HIV-prevention pill had contracted a rare, drug-resistant strain of the virus.
The patient is a gay man, who had been taking Tuvada daily since January 2016, BuzzFeed reports.
According to HIV specialist Howard Grossman, who presented the findings at the 2016 Research for Prevention conference in Chicago, the levels of tenofovir and emtricitabine – the active drugs in the pill – were high enough to provide near-complete protection from the virus.
The man has a long-term, HIV-undetectable partner, but said that they have had condomless sexual encounters with men outside of the relationship. Experts have deduced that the virus was transmitted from one of these encounters, as the patient’s strain did not match that of his partners.
While the results may seem alarming, Mitchell Warren, executive director of HIV advocacy group AVAC, told BuzzFeed News that this is only the second case out of someone contracting HIV while on PrEP out of “hundreds of thousands” of patients.
“We know PrEP is not 100% effective, and that’s something we need to be saying loudly and clearly,” he added.
He continued: “Truthfully, PrEP is the best intervention we’ve ever had to prevent HIV.”
“I don’t think we’re going to see some huge explosion of failures. I think it’s going to be a sort of trickle, if anything.”
“We have now seen hundreds of thousands of people on oral PrEP, and we’ve only seen two cases of so-called breakthrough infections.”
“We know PrEP is not 100% effective, and that’s something we need to be saying loudly and clearly.”
Warren also suggested that more needs to be done to track drug-resistant HIV. “This is a virus that’s been around for 35 years — it’s so variable and mutates so rapidly — and that’s one of the biggest challenges for developing any prevention,” he explained.