A once-promising genital herpes vaccine has failed in a large clinical trial, reported researchers. Researchers found that the vaccine efficacy was only 20%.
About 8,300 uninfected women, aged 18-30 years, were part of this new study. Researchers found that the experimental genital herpes shot was only mildly effective against herpes simplex virus type 1 (HSV-1), which commonly causes cold sores and sometimes genital herpes; and not at all effective against herpes simplex virus 2 (HSV-2), the most common cause of genital herpes.
Study co-author Dr. Peter Leone said, "We will need to take a 'different type of vaccine approach' in order to find something that works against both viruses."