The study was presented today in San Francisco, at the American Society for Microbiology's 46th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy.
The researchers included Peter Leone, MD, of the University of North Carolina at Chapel Hill.
Before you explore their study, take a moment to review these basic facts on genital herpes:
- It is spread through sex.
- It is most commonly caused by HSV-2.
- It can also be caused by herpes simplex virus type 1 (HSV-1).
At least 45 million people in the U.S. -- one in five adults and adolescents -- have carried an HSV virus, but many of them don't know it, according to the CDC.
That is, it's possible to spread the herpes virus even if you don't have herpes sores.
Leone and colleagues studied 129 people with evidence of HSV-2 virus infection from blood tests. Some had a history of outbreaks of genital herpes while others didn't.
The researchers randomly split participants into two groups.
Participants in one group took Famvir for 42 days. Then they took a two-week break. Lastly, they took pills containing no medicine (placebo) for 42 more days.
Participants in the other group took the same pills in reverse order. They took the placebo first for 42 days, followed by a two-week break, and then they took Famvir for 42 days.
Participants didn't know which pills were Famvir.
Each participant also provided daily swabs from his or her genital area. The researchers analyzed those swabs for HSV-2.
Participants with a history of genital herpes outbreaks showed reduced HSV-2 shedding while taking Famvir, but not with the placebo.
But HSV-2 shedding wasn't curbed by Famvir in people who had never had a genital herpes outbreak.
Famvir therapy "suppresses HSV-2 shedding in patients with a clinical history of genital herpes," write Leone and colleagues.
Leone notes financial ties to Novartis, the drug company that makes Famvir. Novartis is a WebMD sponsor.