Famciclovir vs. aciclovir in immunocompetent patients with recurrent genital herpes infections: a parallel-groups, randomized, double-blind clinical trial

Br J Dermatol. 2001 Apr;144(4):818-24. doi: 10.1046/j.1365-2133.2001.04139.x.


Background: Twice-daily therapy with famciclovir (FCV) was shown to be effective for episodic therapy for recurrent genital herpes in a large placebo-controlled trial. However, no study has been published to date comparing FCV and aciclovir (ACV).

Objectives: We have evaluated the effectiveness of FCV vs. ACV in the treatment of recurrent genital herpes infection.

Methods: A multicentre, double-blind, double-placebo, randomized, parallel-design study, assessed for equivalence, was conducted. As the analysis was based on confidence intervals, a difference of lesion healing time between ACV and FCV (Delta) of 1.05 days with a standard deviation of 2.30 days was chosen. Two hundred and four outpatients were included. Patients self-initiated oral therapy with 125 mg of FCV twice daily or ACV 200 mg five times daily for 5 days. The principal end-point of the study was the complete healing of lesions. Duration of the complete resolution of all symptoms, and safety were also considered.

Results: The mean healing time was 5.1 days and 5.4 days for FCV and ACV, respectively, with a crude value of Delta = 0.25 days (CI 95%: -0.32; 0.82) in the intent-to-treat population. Therefore, the confidence interval for the difference between the two treatments lies entirely within the equivalence range (-1.05-1.05). The value of Delta in the per-protocol population [0.35 day (CI 95%: -0.24; 0.93)] was comparable between the two groups. No differences were detected in the proportion of patients having complete healing at the different days of evaluation as well as in the duration until the complete resolution of all the symptoms. The frequency, nature and severity of adverse events did not differ among the two treatment groups.

Conclusions: Twice-daily FCV was as effective and safe in the treatment of recurrent genital herpes simplex virus infection as five times daily ACV.

Publication types

  • Clinical Trial
  • Clinical Trial, Phase III
  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2-Aminopurine / adverse effects
  • 2-Aminopurine / analogs & derivatives*
  • 2-Aminopurine / therapeutic use*
  • Acyclovir / adverse effects
  • Acyclovir / therapeutic use*
  • Adult
  • Aged
  • Aged, 80 and over
  • Antiviral Agents / adverse effects
  • Antiviral Agents / therapeutic use*
  • Double-Blind Method
  • Famciclovir
  • Female
  • Herpes Genitalis / drug therapy*
  • Herpes Genitalis / immunology
  • Humans
  • Immunocompetence*
  • Male
  • Middle Aged
  • Prodrugs / adverse effects
  • Prodrugs / therapeutic use*
  • Recurrence
  • Treatment Outcome


  • Antiviral Agents
  • Prodrugs
  • 2-Aminopurine
  • Famciclovir
  • Acyclovir