Pre-exposure prophylaxis (PrEP) to prevent getting HIV may also lower the risk of contracting herpes simplex 2 (HSV-2), MedPage Today reports. Publishing their findings in the Annals of Internal Medicine, researchers conducted a subgroup analysis of a randomized controlled trial of PrEP among heterosexual couples in which one member was HIV positive. None of the participants who were HIV negative at the outset of the study had herpes at that time.

A total of 1,041 of the HIV-negative partners were randomized to receive either tenofovir or Truvada (tenofovir/emtricitabine) as PrEP, while 481 received a placebo. A total of 131 of these participants contracted herpes, including 79 in the PrEP group, for an incidence rate of 5.6 per 100 person years, and 52 in the placebo group, for an incidence rate of 7.7 per 100 person years. Thus, PrEP reduced the chance of acquiring herpes by 30 percent. Out of the 1,044 participants on either PrEP or the placebo who had HSV-2-positive partners, PrEP cut the herpes risk by 33 percent.

Tenofovir has been shown to combat HSV-2 in laboratory experiments, while emtricitabine apparently does not act as such a prophylaxis.

The researchers concluded that “modest protection against HSV-2 is an added benefit of HIV-1 prevention with oral tenofovir-based PrEP.”

To read the MedPage Today story, click here.

To read the study abstract, click here.