Efficacy of valacyclovir vs acyclovir for the prevention of recurrent herpes simplex virus eye disease: a pilot study

Am J Ophthalmol. 2007 Oct;144(4):547-51. doi: 10.1016/j.ajo.2007.06.001. Epub 2007 Aug 9.


Purpose: To compare the efficacy of one-year treatment with valacyclovir vs acyclovir in preventing recurrence of the herpes simplex virus (HSV) eye disease.

Design: Prospective, randomized, clinical trial pilot study.

Methods: Fifty-two immunocompetent patients with a history of recurrent ocular HSV disease were treated at the Ocular Immunology Service, San Raffaele Hospital, Milan, Italy. Twenty-six patients were randomized to the valacyclovir group (one 500 mg tablet daily), and 26 patients were randomized to the acyclovir group (one 400 mg tablet twice daily). The recurrence rate of ocular HSV disease during 12 months of treatment and drug-related side effects were monitored.

Results: Recurrence of any type of ocular HSV disease during the 12-month treatment period was 23.1% in the valacyclovir group, compared with 23.1% in the acyclovir group. No difference between the two groups was observed regarding the nature, frequency, or severity of adverse events. The most frequent adverse events were nausea and headache.

Conclusions: One-year suppression therapy with oral valacyclovir (500 mg tablet daily) was shown to be as effective and as well tolerated as acyclovir (400 mg tablet twice daily) in reducing the rate of recurrent ocular HSV disease.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Acyclovir / adverse effects
  • Acyclovir / analogs & derivatives*
  • Acyclovir / therapeutic use*
  • Administration, Oral
  • Adult
  • Antiviral Agents / adverse effects
  • Antiviral Agents / therapeutic use*
  • Female
  • Humans
  • Keratitis, Herpetic / prevention & control*
  • Male
  • Pilot Projects
  • Prodrugs / adverse effects
  • Prodrugs / therapeutic use*
  • Prospective Studies
  • Secondary Prevention
  • Treatment Outcome
  • Valacyclovir
  • Valine / adverse effects
  • Valine / analogs & derivatives*
  • Valine / therapeutic use


  • Antiviral Agents
  • Prodrugs
  • Valine
  • Valacyclovir
  • Acyclovir