Clinical Science (35)
Authors: Colin Joseph , Prisant Olivier , Cochener Béatrice , Lescale Olivier , Rolland Bénédicte , Hoang‐Xuan Thanh 
Published: September 2010

Comparison of the efficacy and safety of valaciclovir and acyclovir for the treatment of herpes zoster ophthalmicus. (Hospital Morvan, Brest, France) Ophthalmology 2000;107:1507–1511.

This randomized, double‐blinded study compared the efficacy and safety of valaciclovir and acyclovir in immunocompetent patients with herpes zoster ophthalmicus. One hundred ten immunocompetent patients with herpes zoster ophthalmicus diagnosed within 72 h of skin eruption were treated; 56 were allocated to the valaciclovir group and 54 to the acyclovir group. Patients randomized to the valaciclovir group received 2 500‐mg tablets of valaciclovir 3 times daily and 1 tablet of placebo twice daily. Patients in the acyclovir group received 1 800‐mg tablet of acyclovir 5 times daily and 1 tablet of placebo 3 times daily for 7 days. Main outcome measures included the frequency, severity, and duration of ocular complications, patient records of zoster‐associated pain, and the outcome of skin lesions. Tolerance was also assessed on the incidence and types of adverse effects and changes in laboratory parameters. The analysis was mainly descriptive and performed on an intent‐to‐treat basis. Ocular complications of herpes zoster ophthalmicus were similar in the valaciclovir and acyclovir treatment groups. The main complications were conjunctivitis (54% and 52%, respectively), superficial keratitis (39% and 48%, respectively for punctate keratitis; 11 in each group for dendritic keratitis), stromal keratitis (13% in each group) and uveitis (13% and 17%, respectively). The long‐term outcomes of these ocular complications were favorable and similar in both treatment groups. Pain duration, severity, and outcome of skin lesions were similar between groups. Most patients reported prodromal pain. After 1 month, 25% of the patients in the valaciclovir group and 31% in the acyclovir group still reported pain. The percentage of patients experiencing postherpetic neuralgia decreased during follow‐up. The tolerance to acyclovir and valaciclovir was comparable and considered good. The most frequent adverse events were vomiting and edema of the eyelids or face (3%–5%). Three serious adverse events not linked to the study drugs occurred. Valaciclovir is as effective as acyclovir in preventing ocular complications of herpes zoster ophthalmicus, including conjunctivitis, superficial and stromal keratitis, and pain. Tolerability of the 2 drugs is similar, but the dosing schedule of valaciclovir is simpler.

Comment by Mauricio Orbegozo, MD.

This is a study comparing the efficacy in the treatment of herpes zoster ophthalmicus and its ophthalmologic complications and sequelae between valaciclovir and acyclovir. The initial review of the incidence and the associated ophthalmologic complications of untreated herpes zoster ophthalmicus is concise and educational for physicians who do not interact with these kind of patients frequently. As pain physicians, it is part of our daily practice to deal with patient compliance to the medication treatment we prescribe. In this sense, this article provides comparison between 2 medications that are very similar in the efficacy profiles as well as their control of complications, but with acyclovir there is question of whether patients might be more compliant to the lower dosing frequency of valaciclovir. Results overall are similar between both drugs, but in terms of complications, although not statistically significant, the percentage is consistently lower with valaciclovir than acyclovir. The fact stated in this article regarding the bioavailability of valaciclovir being similar to that of intravenous acyclovir may account for this. The high incidence of irreversible ophthalmic complications such as anatomical loss of an eye (50%–70%) in untreated herpes zoster ophthalmicus makes the question of patient compliance with treatment a crucial one. As physicians, we may not realize that for a patient there might be a significant difference between interrupting their daily life 3 times to take a medication instead of 5 times. In summation, this is a well‐designed study with valid conclusions that would impact our practice of medicine.