KHOPOTSO: The results of the study, which was called HPTN 039, were announced at a workshop in Johannesburg, by Professor Connie Celum, of the University of Washington.

Prof. CONNIE CELUM: We’€™re surprised because the epidemiologic and biologic data were so compelling. And we are definitely very disappointed. This is an important result for HIV prevention and tells us that this dose of Acyclovir is not going to prevent HIV acquisition.    

KHOPOTSO: The study involved just over 3000 participants and all had a sexually transmitted infection known as HSV-2 or more commonly, herpes, but didn’€™t have HIV. Half were heterosexual women from three sites in Africa ‘€“ Zambia, Zimbabwe and South Arica. The other half comprised homosexual men from the United States and Peru, in Latin America. They were randomly assigned to a double-blinded trial where half the volunteers received the study drug, 400 mg of Acyclovir twice daily. The others received a similar pill, but without medicinal properties, called a placebo. Out of 3000 who participated in the 18-month trial, a total of 139 contracted HIV. To break it down, 75 from the Acyclovir arm became HIV-positive, with 64 from the placebo group also becoming infected.

Prof. CONNIE CELUM: There’€™s no difference in HIV acquisition between the two arms’€¦ 139 participants became HIV-infected during the study, so the overall incidence rate was 3.6.

KHOPOTSO: A similar study using Acyclovir was completed in the area of Mwanza, in Tanzania, recently and showed that Acyclovir does not prevent HIV infection in herpes-positive individuals. Celum says both results are disappointing in light of research suggesting what epidemiologists have for many years called a link between herpes and HIV. This link was the basis for the initiation of the study.

Prof. CONNIE CELUM: Many, many studies over 20 years’€™ time now from every continent have suggested that herpes and HIV fuel each other and that part of why the HIV epidemic is as bad as it is, is due to herpes’€¦ The data suggests that herpes makes someone more susceptible to HIV as well as if they have both HIV and herpes, more infectious’€¦ If someone has HIV it also increases the frequency in which the herpes reactivates, making it easier to transmit herpes. So, round and round the circle goes. And epidemiologists have taken these data from multiple studies and estimated that maybe as many as half of new HIV infections in Africa could be due to herpes’€¦

KHOPOTSO: This research has now spawned well over 20 studies.  

Prof. CONNIE CELUM: Heterosexual men and women had about a three-fold higher risk of becoming HIV-infected if they had herpes and for men who have sex with men it’€™s a little lower, about two-fold’€¦ Why would herpes do that? Well, one is we know that herpes ‘€“ when it reactivates, can cause ulcerations and we call those macroscopic ulcerations ‘€“ but we also know that herpes reactivates frequently and often without visible ulcers.              

KHOPOTSO: It is these ulcers that researchers believe are a risk factor to HIV infection in people who have herpes. But the HPTN 039 study failed to prove the two decades’€™ long scientific assumption that herpes can lead to HIV infection. Cynthia Kubheka is one of the women who participated.

CYNTHIA KUBHEKA: It was a disappointment to the researchers that Acyclovir does not prevent HIV. But to me it’€™s not a disappointment because since I’€™ve started using Acyclovir, I don’€™t have many outbreaks. And number two – since this study was initiated I now know more about HIV and my HSV-2 status. Now I know that I have herpes and I know how to behave sexually. I’€™ve even encouraged my husband to go and test for HIV and for HSV-2 and now we are both using condoms and we don’€™t have recurring outbreaks’€¦ I will continue taking part in clinical trials. I’€™ll definitely continue. I’€™ve learned a lot of things.

KHOPOTSO: Dr Nomonde Xundu is the Chief Director responsible for TB, STIs and HIV/AIDS in the national Department of Health. She reflects on a string of disappointing results on the HIV prevention front as she reacts to the latest finding.  

Dr NOMONDE XUNDU: We have the same results out of trials and the lesson that I’€™m getting out of these things is it is the long haul approach to finding solutions and bashing on and continuing being hopeful, working hard’€¦ to look for better answers’€¦ Now we know that suppressive therapy for herpes is not going to work to assist us with reduced acquisition of HIV, which we didn’€™t know previously. There was a theory that says, ‘€œIt might work’€’€¦ It’€™s in the nature of science. You find some of it encouraging, some of it disappointing, but also channelling in a more informed way as to what the questions then should be. We, unfortunately, are at that point with HIV. Many things are known, but yet many other things are unknown and one way of finding these answers is through this kind of research.

KHOPOTSO: Although it has failed to prove effective in reducing HIV risk in people who have genital herpes, Acyclovir remains successful in the suppression of genital herpes.