HSV-2 Suppression for HIV Prevention
What is HSV-2 Suppression for HIV Prevention?
Why is HSV-2 suppressive treatment or HSV-2 prevention a possible HIV risk reduction strategy? Genital herpes is caused by the sexually transmitted virus herpes simplex virus type 2 (HSV-2). There is a possibility that prevention of HSV-2 or suppressive use of antivirals—acyclovir and valcyclovir—can reduce the recurrence of HSV-2 lesions. There is also the possibility that HSV-2 infection can be prevented by a vaccine. This may have the added benefit of reducing the risk of HSV-2 infected/HIV-uninfected people acquiring HIV, and of HSV-2/HIV dually-infected people transmitting HIV to their sexual partners. HSV-2 is found in 20 to 30 percent of HIV-uninfected people in industrialized world compared to 40 to 70 percent of HIV-uninfected people in resource-limited settings. HSV-2 prevalence is highest (>80%) in HIV-infected people. Therefore, preventing HSV-2 or treating HSV-2 in both HIV negative and positive people could potentially have an impact on the HIV epidemic.
HSV-2 Suppression Investment
Prevention of herpes simplex virus type 2 (HSV-2) infections in HIV-negative people may prove to be an effective element in an HIV prevention strategy. While HSV-2 suppression with acyclovir and its analogues has not been shown to affect HIV acquisition, research on other therapeutic and prophylactic methods is ongoing and some basic questions continue to be pursued. In 2014, a total of US$9.9 million was provided for HSV-2 vaccine research from the US NIH and the Canadian Institutes of Health Research, an increase of US$4.1 million over 2013. As in previous years, commercial investors were often subsidized by public-sector institutions, such as the US NIH. Pharmaceutical and biotechnology companies investing in HSV-2 vaccine R&D include Agenus Inc., GSK, Genoccea Biosciences, Juvaris and Vical.