Two New Studies Find PrEp Reduces The Risk Of HIV Infection By 86 Percent


The days of taking Truvada once-a-day may soon be over.

Past research has claimed that daily use of PrEP can dramatically lower one’s chances of being infected with HIV. Now, two new studies support those claims, but one of the studies takes it a step further.

500 gay men in the U.K. participated in a study retest the effectiveness of taking the standard, once-a-day dose of PrEP. Researchers found this strategy lowered one’s risk for HIV infection by 86 percent.

400 gay men participated in second study jointly conduced in France and Canada and looked at what happened when PrEP was taken on a less regimented schedule. Rather than taking a pill everyday, they took two pills between 2 and 24 hours prior to having sex with another man, followed by another two pills 24 and 48 hours after sex. The second study found the exact same degree of protection — 86 percent — as the standard, once-a-day regime.

“These results are extremely exciting and show PrEP is highly effective at preventing HIV infection in the real world,” said Sheena McCormack, Professor of Clinical Epidemiology at the MRC Clinical Trials Unit at UCL, and Chief Investigator of the U.K. study. “Concerns that PrEP would not work so well in the real world were unfounded. These results show there is a need for PrEP, and offer hope of reversing the epidemic among men who have sex with men.”

But don’t get too excited yet, fellas.

In a statement released by the CDC, Dr. Jonathan Mermin said that it’s still too soon for people to completely abandon the once-a-day regimen, saying more research needs to be conducted.

Mermin noted that the new strategy was only tested on men who were having sex an average of 10 times per month with eight partners every two months, which means that some of them were taking as many as eight pills per week, exceeding the once-per-day dosage.

“Researchers do not yet know if this regimen will work among MSM who have sex less frequently and would therefore be taking PrEP less often,” Mermin said.

Still, the new results are encouraging.

“I am immensely pleased and overwhelmed, a little emotional even,” said study participant Stefan Laros. “[F]or the first time in 30 years I feel there is hope for people like me, who struggle with consistent condom use, but who want to protect themselves — and just as importantly — their sex partners against HIV infection.”

Related stories:

QUESTION: Is It Finally The Right Time For HIV Negative Guys To Start PrEP?

Ben Patrick Johnson Blames Larry Kramer’s Resistance To PrEP On “Generational Gap”

Is Truvada As Effective At Preventing HIV Infection As We Thought? Maybe not.