New Herpes Drugs on the Way
April 1, 2002 -- When Zovirax hit the market in the 1970s, it was a huge relief for millions of people suffering from oral and genital herpes. Although the original formula has been modified and improved over the years, it still doesn't work for everyone. Some people continue to experience frequent, painful outbreaks. But that may soon change. Researchers report they've developed an entirely new class of herpes drug.
In the April issue of Nature Medicine, two pharmaceutical companies describe their findings. The three compounds are not the same, but they fight the herpes simplex virus (HSV) in the same way -- by preventing its DNA from duplicating. Since this new mechanism is different from that of currently available drugs, the new compounds -- all in pill form and known collectively as helicase-primase inhibitors -- could potentially help people who are resistant to Zovirax.
Gerald Kleymann and colleagues at Bayer AG in Wuppertal, Germany, tested their new compound on mice.
They found that it shortens healing time, prevents a rebound reaction after stopping treatment, and reduces the frequency and severity of outbreaks. "This class of drugs has significant potential for the treatment of HSV disease in humans, including those resistant to current medications," they write.
James Crute and colleagues at Boehringer Ingelheim Pharmaceuticals in Ridgefield, Conn., and Laval, Quebec, also found that their compound was quite effective against both oral and vaginal herpes outbreaks in mice.
There were no serious side effects in the test animals with any of the new compounds.
In an editorial accompanying the two reports, Clyde Crumpacker, MD, and Priscilla Schaffer, PhD, of Boston's Beth Israel Deaconess Medical Center write that the drugs do look quite promising. Still, while they may suppress herpes outbreaks, they are not a cure -- the disease is still active in the body and can be spread to others through intimate contact. They write that continued research should focus on identifying compounds to block the latent, or dormant, stage of the virus, and at developing a vaccine to prevent infection.