Abstract: Objective To investigate and compare the effect and safety of different doses and courses of oral valaciclovir in the treatment of recurrent genital herpes.Methods A multi-center, randomized and double-blind comparative clinical trial was conducted.Patients with recurrent genital herpes were divided into either study group(valaciclovir 500mg twice daily orally for 5 days)or control group (valaciclovir 300mg twice daily orally for 7 days).Vesicle fluid or discharge under crusts was collected from the patients' lesions for HSV culture before treatment and 1,2 days after starting treatment.Patients were observed for therapeutic efficacy and side effects on 1,2,and 7 days after the treatment.Results One hundred and forty two patients were enrolled in this study.Of them,142 were evaluated for safety and 133 for therapeutic effects at the end of the study.No significant difference was observed in the decrease of sign and symptom score or response rate on 1,2,7 days after the treatment(both P>0.05).According to full analysis set(FAS)analysis,the positive rates of HSV culture decreased from 87.50%(before treatment) to 28.85%(1 day after the treatment) and from 92.86% to 54.55% in study and control group, respectively,and there was significant difference in the positive rates of 1 day after the treatment between the two groups(P<0.05).Significant difference was also found using particles per set(PPS)analysis in the positive rates of 1 day after the treatment between the two groups(P<0.05).The occurrence rates of side effects were 0 and 4.23% in the study and control group,respectively.The most common side effects were discomfort in stomach,dizziness and drowsiness.Conclusions The increase in valaciclovir dose could significantly improve the clearance rate of HSV on 1 day after the treatment,and shorten the retention of herpes virus in local lesions during the treatment of recurrent genital herpes.

Key words: Herpes genitalis, Randomized controlled trials, Valaciclovir