A meta-analysis to assess the efficacy of oral antiviral treatment to prevent genital herpes outbreaks

Background Efficacy of oral antiviral therapies, ie, acyclovir, valacyclovir (VACV), and famciclovir, for suppression of recurrent genital herpes was studied at different doses and regimens. Objective We sought to compare the clinical efficacies of the different oral antiviral drugs prescribed prophylactically to suppress recurrent genital herpes. Methods MEDLINE and EMBASE databases were searched for articles on genital herpes and selected antiviral drugs. The selected trials were: parallel randomized clinical trials testing prophylactic oral antiviral treatment of genital herpes versus placebo in immunocompetent and nonpregnant patients. Results Fourteen randomized clinical trials were selected, including a total of 6158 patients. The global relative risk of developing at least one recurrence during the study was reduced by 47% (95% confidence interval 45%-49%) in antiviral drug groups compared with the placebo. The best evaluated regimens, with comparable efficacies, were given twice daily, ie, acyclovir (400 mg twice daily), VACV (250 mg twice daily), and famciclovir (250 mg twice daily), or once daily (VACV 500 mg). Limitations The only end point available for all the studies was the number of patients presenting at least one recurrence of genital herpes during the observation period. Conclusion The results of this first meta-analysis confirmed the high clinical efficacy of oral acyclovir, VACV, or famciclovir for prophylaxis against recurrent genital herpes.